RE: Observer-Moment Measure from Universe Measure

2005-06-15 Thread Jonathan Colvin
Hal wrote:

> Jonathan Colvin writes, regarding the Doomsday argument:
> > There's a simple answer to that one. Presumably, a million 
> years from 
> > now in the Galactic Empire, the Doomsday argument is no longer 
> > controversial, and it will not be a topic for debate. The 
> fact that we 
> > are all debating the Doomsday argument implies we are all 
> part of the 
> > reference class: (people debating the doomsday argument), and we 
> > perforce can not be part of the Galactic Empire.
> 
> Well, I don't want to open up discussion of the DA.  Suffice 
> it to say that good thinkers have spent considerable amounts 
> of time considering it and don't necessarily think that this 
> reply puts it to bed.
> http://www.anthropic-principle.com has an exhaustive discussion.

Since it is coming from Nick B., over-exhaustive :) 
I don't think anybody, Nick included, has yet come up with a convincing way
to define appropriate reference classes. Absent this, the only way to rescue
the DA seems to be a sort of dualism (randomly emplaced souls etc).

> [Regarding measure and size]
> 
> > I find these conclusions counter-intuitive enough to suggest that 
> > deriving measure from a physical fraction of involved reasources is 
> > not the correct way to derive measure. It is not unlike trying to 
> > derive the importance of a book by weighing it.
> 
> Don't be too eager to throw out this concept of measure.  It 
> is fundamental to the Schmidhuber and Tegmark approach to the 
> multiverse.
> It allows deriving why induction works as well as Occam's razor.
> It explains why the universe is lawful and has a simple description.
> It allows us in principle to calculate how likely we are to 
> be in The Matrix or some such simulation vs a basement-level 
> universe.  It is quite an amazing quantity of results from 
> such a simple assumption.
> I don't think you will find anything else like it in philosophy.
> 
> As far as the specific issue of measure and size, suppose you 
> agree that making copies of a structure increases its 
> measure, but you object to the idea that scaling up its size 
> would do so.  Years ago I came up with a thought experiment 
> that adopted the position you have, that size doesn't matter. 
>  (That's what my wife kept telling me, after all...) From 
> that I proved that copies didn't matter either, which wasn't 
> too appealing.  Today I would say that my premise was wrong.  
> Size matters.


Isn't there a counter argument, though? Imagine a Universe of size X, and
that observers have size Y

RE: Observer-Moment Measure from Universe Measure

2005-06-15 Thread "Hal Finney"
Jonathan Colvin writes, regarding the Doomsday argument:
> There's a simple answer to that one. Presumably, a million years from now in
> the Galactic Empire, the Doomsday argument is no longer controversial, and
> it will not be a topic for debate. The fact that we are all debating the
> Doomsday argument implies we are all part of the reference class: (people
> debating the doomsday argument), and we perforce can not be part of the
> Galactic Empire.

Well, I don't want to open up discussion of the DA.  Suffice it to say
that good thinkers have spent considerable amounts of time considering
it and don't necessarily think that this reply puts it to bed.
http://www.anthropic-principle.com has an exhaustive discussion.

[Regarding measure and size]

> I find these conclusions counter-intuitive enough to suggest that deriving
> measure from a physical fraction of involved reasources is not the correct
> way to derive measure. It is not unlike trying to derive the importance of a
> book by weighing it.

Don't be too eager to throw out this concept of measure.  It is
fundamental to the Schmidhuber and Tegmark approach to the multiverse.
It allows deriving why induction works as well as Occam's razor.
It explains why the universe is lawful and has a simple description.
It allows us in principle to calculate how likely we are to be in The
Matrix or some such simulation vs a basement-level universe.  It is
quite an amazing quantity of results from such a simple assumption.
I don't think you will find anything else like it in philosophy.

As far as the specific issue of measure and size, suppose you agree
that making copies of a structure increases its measure, but you object
to the idea that scaling up its size would do so.  Years ago I came up
with a thought experiment that adopted the position you have, that size
doesn't matter.  (That's what my wife kept telling me, after all...)
>From that I proved that copies didn't matter either, which wasn't too
appealing.  Today I would say that my premise was wrong.  Size matters.

Here is a simple example.  Suppose we have a book in a computer memory.
Now we make two copies of the book in memory.  Perhaps you will agree
that this increases its measure.  Maybe the measure doubles, or maybe
it doesn't go up quite that much, but it does increase.

Now suppose we arrange the two copies interleaved in memory.  Instead of
"It was the best of times, it was the worst of times..." in two places,
we have "IItt  wwaass  tthhee  bbeesstt  ooff  ttiimmeess...".  Is this
still two copies, or is it one copy with extra big data representation?
The difference is not so clear.  This should suggest, maybe there isn't
any difference in terms of measure of the two cases.

I have several other examples I have used as well.  In one I have a
pair of electronic computers running exactly the same program side by
side, in lockstep.  This is two instances and arguably the program has
larger measure.  Now I attach wires between the corresponding parts
of the electronic circuits that make up the computers.  Point A in the
left computer is attached to point A in the right computer, and so on
for every circuit element. These wires have variable resistance that
can be smoothly changed from full conductivity to perfect insulation.

When the wires are insulated, there is no interaction between the two
computers and there are two copies.  When the wires are conductive, the
corresponding circuit elements are electrically joined so the system acts
like a single computer that is twice as big.  By varying the resistance
we can smoothly go from one case to the other.

Imagine a conscious program running on this system.  When there are two
computers, perhaps there are two conscious entities, each with their
unique identity.  When there is only one computer, there is only one
consciousness.  Yet we can switch smoothly between the two.  We can go
from two people to one and back!  How much sense does that make?

I wouldn't put it like that today, but if we just focus on measure,
we again go from a pair of computations to a computation that is twice
as big.  It makes sense that the two cases would have the same measure.

>From these and other thought experiments I find that it is not as
surprising as it seems at first to imagine that increasing size increases
measure.  The fact that it follows immediately from Schmidhuber's simple
principle only came to me recently.  I find it interesting and provocative
that these two independent arguments lead to the same conclusion.

Hal Finney



RE: Observer-Moment Measure from Universe Measure

2005-06-15 Thread Jonathan Colvin

Hal Finney wrote:
> > I presume the answer is that rather than look at physical 
> size/weight 
> > of our bodies, one must try to calculate the proportion of the 
> > universe's information content devoted to that part of our beings 
> > essential to being an observer (probably something to do 
> with the amount of grey matter).
> 
> Yes, I think that's right.  Our bodies don't directly 
> contribute to our conscious experiences.
> 
> > But
> > again, this surely changes as we age. My brain (and 
> consciousness) at 
> > age 2 was much smaller than at age 30, and will start to 
> shrink again 
> > as I get senile. Does our measure increase with age?
> 
> I think you meant "decrease", at least in terms of becoming elderly.
> Of course we already know that measure decreases with age due 
> to the continual risk of dying.  But yes, I think this 
> argument would suggest that there is a small decrease in 
> measure due to brain shrinkage.
> It would not be a very large effect, though, I don't think.
> 
> > If we get brain surgery, does
> > our measure diminish?
> 
> You mean if they cut out a piece of your brain?  I guess that 
> would depend on whether it affected your consciousness.  If 
> it did you probably have bigger problems than your measure 
> decreasing.  Your consciousness would change so much that 
> your previous self might not view you as the same person.
> 
> > And once the transhumanist's dream of mental augmentation 
> is possible, 
> > will our measure increase as our consciousness increases?
> 
> Yes, I think so, assuming the brains actually become bigger.  
> Although there is a counter-effect if the brains instead 
> become faster and smaller, as I wrote earlier.  So this 
> raises a paradox, why are we not super-brains?  Perhaps this 
> is an argument against the possibility that this will ever 
> happen, a la the Doomsday Argument (why do we not live in the 
> Galactic Empire with its population billions of times greater 
> than today?).

There's a simple answer to that one. Presumably, a million years from now in
the Galactic Empire, the Doomsday argument is no longer controversial, and
it will not be a topic for debate. The fact that we are all debating the
Doomsday argument implies we are all part of the reference class: (people
debating the doomsday argument), and we perforce can not be part of the
Galactic Empire.

> 
> Although these conclusions may be counter-intuitive, I find 
> it quite exciting to be able to derive any predictions at all 
> from the AUH in the Schmidhuber model.  It suggests that 
> uploading your brain to a computer might be tantamount to 
> taking a large chance of dying; unless you could then 
> duplicate your uploaded brain all over the world, which would 
> greatly increase your measure.  And all this comes from the 
> very simple assumption that the measure of something is the 
> fraction of multiverse resources devoted to it, a simple 
> restatement of the Schmidhuber multiverse model.

I find these conclusions counter-intuitive enough to suggest that deriving
measure from a physical fraction of involved reasources is not the correct
way to derive measure. It is not unlike trying to derive the importance of a
book by weighing it.

Jonathan Colvin



RE: Observer-Moment Measure from Universe Measure

2005-06-15 Thread "Hal Finney"
Jonathan Colvin writes:
> I presume the answer is that rather than look at physical size/weight of our
> bodies, one must try to calculate the proportion of the universe's
> information content devoted to that part of our beings essential to being an
> observer (probably something to do with the amount of grey matter).

Yes, I think that's right.  Our bodies don't directly contribute to our
conscious experiences.

> But
> again, this surely changes as we age. My brain (and consciousness) at age 2
> was much smaller than at age 30, and will start to shrink again as I get
> senile. Does our measure increase with age?

I think you meant "decrease", at least in terms of becoming elderly.
Of course we already know that measure decreases with age due to the
continual risk of dying.  But yes, I think this argument would suggest
that there is a small decrease in measure due to brain shrinkage.
It would not be a very large effect, though, I don't think.

> If we get brain surgery, does
> our measure diminish?

You mean if they cut out a piece of your brain?  I guess that would
depend on whether it affected your consciousness.  If it did you probably
have bigger problems than your measure decreasing.  Your consciousness
would change so much that your previous self might not view you as the
same person.

> And once the transhumanist's dream of mental
> augmentation is possible, will our measure increase as our consciousness
> increases?

Yes, I think so, assuming the brains actually become bigger.  Although
there is a counter-effect if the brains instead become faster and
smaller, as I wrote earlier.  So this raises a paradox, why are we not
super-brains?  Perhaps this is an argument against the possibility that
this will ever happen, a la the Doomsday Argument (why do we not live
in the Galactic Empire with its population billions of times greater
than today?).

Although these conclusions may be counter-intuitive, I find it quite
exciting to be able to derive any predictions at all from the AUH in the
Schmidhuber model.  It suggests that uploading your brain to a computer
might be tantamount to taking a large chance of dying; unless you could
then duplicate your uploaded brain all over the world, which would greatly
increase your measure.  And all this comes from the very simple assumption
that the measure of something is the fraction of multiverse resources
devoted to it, a simple restatement of the Schmidhuber multiverse model.

Hal Finney



RE: Observer-Moment Measure from Universe Measure

2005-06-15 Thread Jonathan Colvin
Hal wrote: 
> I wanted to add a few points to my earlier posting about how 
> to derive OM measure in a Schmidhuberian multiverse model.
> 
> The method is basically to take all the universes where the 
> OM appears and to sum up the contribution they make to the OM 
> measure.  However, the key idea is that this contribution has 
> two components.  One is the measure of the universe.  The 
> greater the measure of the universe, the greater the 
> contribution to OM measure.  But the other is the fraction of 
> the universe that is involved in the OM.  This means that a 
> smaller universe that contains an OM gives a greater fraction 
> of its measure as its contribution to the OM measure.  
> Smaller universes make more contribution than larger ones.
> 
> This last step may seem ad hoc but in fact it can be seen in 
> a very natural way.  It can be thought of as a two step way 
> to output the description of a given OM: first write a 
> program to output a universe with the OM in it, then write a 
> program to take that universe and output the OM.  We can 
> think of combining these two programs into one: write a 
> program that outputs the OM.  Then, the sum of the measure of 
> all such programs is the measure of the OM.


Ok, this second step I don't get. This implies that our measure is dependant
on our physical size. If I weigh 50 times as much as an adult than as I do
as a baby (my fraction of the universe has increased by a factor of 50),
then this implies that my measure should also have increased by a factor of
50. This doesn't seem right. Why should my measure depend on my physical
size? Should I take to stuffing my face with donuts at every opportunity to
increase my measure? How about if I hang lead weights from my belt? Does
that increase my measure? 

I presume the answer is that rather than look at physical size/weight of our
bodies, one must try to calculate the proportion of the universe's
information content devoted to that part of our beings essential to being an
observer (probably something to do with the amount of grey matter). But
again, this surely changes as we age. My brain (and consciousness) at age 2
was much smaller than at age 30, and will start to shrink again as I get
senile. Does our measure increase with age? If we get brain surgery, does
our measure diminish? And once the transhumanist's dream of mental
augmentation is possible, will our measure increase as our consciousness
increases?

Jonathan Colvin



Re: Observer-Moment Measure from Universe Measure

2005-06-15 Thread "Hal Finney"
I wanted to add a few points to my earlier posting about how to derive
OM measure in a Schmidhuberian multiverse model.

The method is basically to take all the universes where the OM appears
and to sum up the contribution they make to the OM measure.  However,
the key idea is that this contribution has two components.  One is the
measure of the universe.  The greater the measure of the universe, the
greater the contribution to OM measure.  But the other is the fraction
of the universe that is involved in the OM.  This means that a smaller
universe that contains an OM gives a greater fraction of its measure
as its contribution to the OM measure.  Smaller universes make more
contribution than larger ones.

This last step may seem ad hoc but in fact it can be seen in a very
natural way.  It can be thought of as a two step way to output the
description of a given OM: first write a program to output a universe
with the OM in it, then write a program to take that universe and output
the OM.  We can think of combining these two programs into one: write a
program that outputs the OM.  Then, the sum of the measure of all such
programs is the measure of the OM.

That last sentence is merely the definition of measure in a Schmidhuberian
context - the measure of anything is the fraction of all programs that
output that thing.  It IMPLIES the formula I described for downgrading a
universe's contribution to an OM by virtue of the relative size of the OM
compared to the universe.  It can be said that we have derived and proven
that relationship by assuming this fundamental definition of measure.

Note that we could also write a program to output an OM without regard
to creating a universe first.  However, I believe that at least for
observers like us, it will always be a much simpler program to first
create a universe and then find the OM in it.  This lets evolution work
and everything is simple.  Ultimately, this allows the AUH (all universe
hypothesis, ie the multiverse exists) to JUSTIFY the belief that we are
not brains (or OMs) in vats, that the universe is probably real.

Okay, so that's just restating what I had before in different words,
explaining it from a different perspective that might be more obvious.
Here are a couple of interesting additions.

First, what about our universe?  Why is it so damn big?  If the measure
of an OM is smaller in a big universe, the AUH should predict that
the universe is no bigger than it needs to be.  Yet, looking around,
our universe looks a lot bigger than necessary.  There's a lot of
wasted space.

I conclude that it is likely that the universe is not in fact much
bigger than it needs to be.  It actually needs to be as big as it is.
This might imply that intelligent life is extremely rare in universes
like ours.  Only by creating a truly enormous universe can we have a
good chance of creating observers.

Let me expand on this a little.  All universes exist.  Some have
complex laws of physics and some are simple.  Some have complex initial
conditions and some are simple.  Physicists believe that our universe
is relatively simple by both measures.  The laws of physics are not
completely understood but the ones we know have a very simple mathematical
formulation.  And the initial conditions also appear to represent a very
smooth and uniform condition immediately after the Big Bang.  The bottom
line is that you would not have to write a very big program to simulate
our universe.

Yet, even with these simple laws, our universe supports life that can
evolve into consciousness.  That's pretty amazing, maybe.  What are
the odds that another universe with equally simple laws could do so?
We know that our own physical laws appear to be relatively "fine tuned"
such that even a tiny change in various properties would cause life as
we know it to be impossible.  That suggests that maybe it is not so
easy to have life.  Maybe almost no universes with laws as simple as
ours create life.

And, maybe life is not all that easy to create even in our universe.
What if life, at least intelligent life, is overwhelmingly unlikely,
even in a universe as well suited as our own?  Maybe we need ten billion
light years' worth of galaxies, stars and planets in order to have a
decent chance of evolving life.  Maybe, in short, our universe is as
big as it needs to be, given our laws of physics, to allow life to evolve.

There may be other sets of laws of physics that would be more fecund,
where life could evolve more easily.  Those might get by with smaller
universes.  But if so, the AUH would predict that such universes would
have much more complicated laws of physics and/or initial conditions
than our own.  Otherwise we would live there.

Given that the universe is as big as we see, and given the AUH, we can
predict that it is not full of intelligent life.  We can predict that
there should be almost no other intelligent civilizations within the
universe.  This then solves the Fermi paradox - where are the

Re: Re-Observer-Moment Measure from Universe Measure

2005-06-14 Thread Bruno Marchal


Le 14-juin-05, à 00:35, George Levy a écrit :




Bruno Marchal wrote:


Godel's theorem:
~Bf -> ~B(~Bf),

which is equivalent to B(Bf -> f) -> Bf,




Just a little aside a la Descartes + Godel: (assume that "think" and 
"believe" are synonymous and that f = "you are")





All right. Of course this follows that for any p in the language of the 
machine, we have indeed that the machine can prove


   B(Bp -> p) -> Bp

That is: the machine does prove its Lob's theorem.  (in my post to 
Brent f was the constant "FALSE").









B(Bf -> f) -> Bf can be rendered as:
If you believe that "if you think that you are therefore you are", 
then you think you are.




Nice! This makes a relation between Lob's theorem (which generalizes 
Godel's second incompleteness theorem) and Descartes systematic 
doubting procedure. The link exists already with Godel's theorem. If 
you look at the "arithmetical placebo phenomenon" (in my SANE paper), 
you are relating Descartes and the Placebo. Quite cute!







That's what Descartes thought!



I agree essentially. See Slezak for a pionering and readable paper 
relating Godel and Descartes:


SLEZAK P., 1983, Descartes 's Diagonal Deduction, Brit. J. Phil. 
Sci. 34, pp. 13-36.


And this is related also with the debate on Godel and Mechanism 
(against Penrose and Lucas), on which Slezak wrote a paper, which could 
be needed for the reading of its Godelian reading of Descartes.


SLEZAK P., 1982, Gödel's Theorem and the Mind, Brit. J. Phil. Sci. 
33, pp. 41-52.


Bruno

http://iridia.ulb.ac.be/~marchal/




Re-Observer-Moment Measure from Universe Measure

2005-06-13 Thread George Levy

Bruno Marchal wrote:


Godel's theorem:
~Bf -> ~B(~Bf),

which is equivalent to B(Bf -> f) -> Bf,   




Just a little aside a la Descartes + Godel: (assume that "think" and 
"believe" are synonymous and that f = "you are")


B(Bf -> f) -> Bf can be rendered as:
If you believe that "if you think that you are therefore you are", then 
you think you are.


That's what Descartes thought!

:-)George



Re: Observer-Moment Measure from Universe Measure

2005-06-13 Thread Bruno Marchal

Hi Brent,

You didn't answer my last post where I explain that Bp is different 
from Bp & p.
I hope you were not too much disturbed by my "teacher's" tone (which 
can be enervating I imagine). Or is it because you don't recognize the 
modal form of  Godel's theorem:


~Bf -> ~B(~Bf),

which is equivalent to B(Bf -> f) -> Bf,   by simple contraposition 
"p -> q" is equivalent with "~p -> ~q", and using also that "~p" is 
equivalent to "p -> f", where f is put for "false".


This shows that for a consistent (~Bf) machine, although Bf -> f is 
true, it cannot be proved by the machine. Now (Bf & f) -> f trivially. 
So Bf and Bf & f are not equivalent for the machine

(although they are for the "guardian angel").


Bruno


http://iridia.ulb.ac.be/~marchal/



RE: Observer-Moment Measure from Universe Measure

2005-06-12 Thread Saibal Mitra
- Original Message - 
From: "Brent Meeker" <[EMAIL PROTECTED]>
To: "Saibal Mitra" <[EMAIL PROTECTED]>
Sent: Friday, June 10, 2005 06:41 PM
Subject: RE: Observer-Moment Measure from Universe Measure


>
>
> >-Original Message-
> >From: Saibal Mitra [mailto:[EMAIL PROTECTED]
> >Sent: Friday, June 10, 2005 11:39 PM
> >To: Brent Meeker; everything
> >Subject: Re: Observer-Moment Measure from Universe Measure
> >
> >
> >
> >- Original Message -
> >From: "Brent Meeker" <[EMAIL PROTECTED]>
> >To: "Saibal Mitra" <[EMAIL PROTECTED]>
> >Sent: Wednesday, June 08, 2005 02:23 PM
> >Subject: RE: Observer-Moment Measure from Universe Measure
> >
> >
> >>
> >>
> >> >-Original Message-
> >> >From: Saibal Mitra [mailto:[EMAIL PROTECTED]
> >> >Sent: Wednesday, June 08, 2005 1:16 PM
> >> >To: Patrick Leahy; Hal Finney; [EMAIL PROTECTED]; [EMAIL PROTECTED]
> >> >Cc: everything-list@eskimo.com
> >> >Subject: Re: Observer-Moment Measure from Universe Measure
> >> >
> >> >
> >> >I think one should define an observer moment as the instantaneous
> >> >description of the human brain. I.e. the minimum amount of information
> >you
> >> >need to simulate the brain of a observer. This description changes
over
> >time
> >> >due to interactions with the environment. Even if there were no
> >interactions
> >> >with the environment the description would change, but this change is
> >fixed
> >> >by the original description.
> >>
> >> That means that, supposing the brain is a classical, the "moment"
cannot
> >be
> >> defined by a description of values, omitting rates; just as the path of
a
> >> ballistic projectile cannot be specified by it location, omitting its
> >velocity.
> >> But to include rates means an implicit introduction of time and
continuity
> >of
> >> OMs.  This implies that OMs form causal chains and it makes no sense to
> >talk
> >> about the same OM being in two different chains.
> >
> >
> >That's true in an isolated personal universe that is not interacting with
an
> >'outside world'. I could, e.g. take your brain and simulate that on a
> >computer. The evolution equations for your brain are deterministic, so
the
> >simulation will describe a unique chain of causal links provided you fix
the
> >boundary conditions.
> >
> >If the personal universe is embedded in another universe (like in our
case),
> >then the evolution equations will be constantly perturbed.
> >
> >
> >
> >
> >>
> >> But a lot of the motivation for OMs comes from the brain *not* being
> >classical;
> >> from the idea that the brain gets "copied" into Everett's multiple
> >relative
> >> states or MWIs.  Decoherence in the brain is very much faster than the
> >> neurochemical processes - that's why it's approximately classical.  So
> >what is
> >> going on when QM predicts different OMs?  From Everett's point of view
the
> >> brain must be treated as part of the QM system and it gets "copied" -
but
> >not
> >> by itself.  Its description must include its entanglement with the
quantum
> >> systems observed.  So it seems that in either case, classical or
quantum,
> >an OM
> >> as a description of a brain state, has links outside itself.  In the
> >classical
> >> case it has casual links in time.  In the QM case it has Hilbert space
> >links to
> >> what has been observed.
> >
> >
> >I agree. But the entangled state of a brain with the rest of the universe
in
> >the MWI corresponds to an ensemble of different worlds such that in each
> >member of the ensemble the brain is in some definite state.
> >
> >
> >>
> >> >So, I see no problem with Hal's way of thinking about OMs
> >> >
> >> >
> >> >Observers are can be thought of as their own descriptions and thus
> >universes
> >> >in their own right. Observer moments are observers in particular
states
> >i.e.
> >> >their ''personal'' universe being in a certain state. The causal
relation
> >> >between successive states is already defined when we specify which
> >observer
> >> >we are talking about. i.e., we have already specified the laws of
physics
>

Re: Observer-Moment Measure from Universe Measure

2005-06-12 Thread Saibal Mitra

- Original Message - 
From: "Brent Meeker" <[EMAIL PROTECTED]>
To: "Saibal Mitra" <[EMAIL PROTECTED]>
Sent: Sunday, June 12, 2005 02:43 AM
Subject: RE: Observer-Moment Measure from Universe Measure


>
>
> >-Original Message-
> >From: Saibal Mitra [mailto:[EMAIL PROTECTED]
> >Sent: Sunday, June 11, 2000 4:01 PM
> >To: Brent Meeker; ":everything-list"@eskimo.com
> >Subject: Re: Observer-Moment Measure from Universe Measure
> >
> >
> >
> >- Original Message -
> >From: "Brent Meeker" <[EMAIL PROTECTED]>
> >To: "Saibal Mitra" <[EMAIL PROTECTED]>
> >Sent: Friday, June 10, 2005 06:41 PM
> >Subject: RE: Observer-Moment Measure from Universe Measure
> >
> >
> >>
> >>
> >> >-----Original Message-
> >> >From: Saibal Mitra [mailto:[EMAIL PROTECTED]
> >> >Sent: Friday, June 10, 2005 11:39 PM
> >> >To: Brent Meeker; everything
> >> >Subject: Re: Observer-Moment Measure from Universe Measure
> >> >
> >> >
> >> >
> >> >- Original Message -
> >> >From: "Brent Meeker" <[EMAIL PROTECTED]>
> >> >To: "Saibal Mitra" <[EMAIL PROTECTED]>
> >> >Sent: Wednesday, June 08, 2005 02:23 PM
> >> >Subject: RE: Observer-Moment Measure from Universe Measure
> >> >
> >> >
> >> >>
> >> >>
> >> >> >-Original Message-
> >> >> >From: Saibal Mitra [mailto:[EMAIL PROTECTED]
> >> >> >Sent: Wednesday, June 08, 2005 1:16 PM
> >> >> >To: Patrick Leahy; Hal Finney; [EMAIL PROTECTED]; [EMAIL PROTECTED]
> >> >> >Cc: everything-list@eskimo.com
> >> >> >Subject: Re: Observer-Moment Measure from Universe Measure
> >> >> >
> >> >> >
> >> >> >I think one should define an observer moment as the instantaneous
> >> >> >description of the human brain. I.e. the minimum amount of
information
> >> >you
> >> >> >need to simulate the brain of a observer. This description changes
> >over
> >> >time
> >> >> >due to interactions with the environment. Even if there were no
> >> >interactions
> >> >> >with the environment the description would change, but this change
is
> >> >fixed
> >> >> >by the original description.
> >> >>
> >> >> That means that, supposing the brain is a classical, the "moment"
> >cannot
> >> >be
> >> >> defined by a description of values, omitting rates; just as the path
of
> >a
> >> >> ballistic projectile cannot be specified by it location, omitting
its
> >> >velocity.
> >> >> But to include rates means an implicit introduction of time and
> >continuity
> >> >of
> >> >> OMs.  This implies that OMs form causal chains and it makes no sense
to
> >> >talk
> >> >> about the same OM being in two different chains.
> >> >
> >> >
> >> >That's true in an isolated personal universe that is not interacting
with
> >an
> >> >'outside world'. I could, e.g. take your brain and simulate that on a
> >> >computer. The evolution equations for your brain are deterministic, so
> >the
> >> >simulation will describe a unique chain of causal links provided you
fix
> >the
> >> >boundary conditions.
> >> >
> >> >If the personal universe is embedded in another universe (like in our
> >case),
> >> >then the evolution equations will be constantly perturbed.
> >> >
> >> >
> >> >
> >> >
> >> >>
> >> >> But a lot of the motivation for OMs comes from the brain *not* being
> >> >classical;
> >> >> from the idea that the brain gets "copied" into Everett's multiple
> >> >relative
> >> >> states or MWIs.  Decoherence in the brain is very much faster than
the
> >> >> neurochemical processes - that's why it's approximately classical.
So
> >> >what is
> >> >> going on when QM predicts different OMs?  From Everett's point of
view
> >the
> >> >> brain must be treated as part of the QM system and it gets
"copied" -
> >but
> >> >not
>

RE: Observer-Moment Measure from Universe Measure

2005-06-11 Thread Saibal Mitra
- Original Message - 
From: "Brent Meeker" <[EMAIL PROTECTED]>
To: "Saibal Mitra" <[EMAIL PROTECTED]>
Sent: Wednesday, June 08, 2005 02:23 PM
Subject: RE: Observer-Moment Measure from Universe Measure


>
>
> >-Original Message-
> >From: Saibal Mitra [mailto:[EMAIL PROTECTED]
> >Sent: Wednesday, June 08, 2005 1:16 PM
> >To: Patrick Leahy; Hal Finney; [EMAIL PROTECTED]; [EMAIL PROTECTED]
> >Cc: everything-list@eskimo.com
> >Subject: Re: Observer-Moment Measure from Universe Measure
> >
> >
> >I think one should define an observer moment as the instantaneous
> >description of the human brain. I.e. the minimum amount of information
you
> >need to simulate the brain of a observer. This description changes over
time
> >due to interactions with the environment. Even if there were no
interactions
> >with the environment the description would change, but this change is
fixed
> >by the original description.
>
> That means that, supposing the brain is a classical, the "moment" cannot
be
> defined by a description of values, omitting rates; just as the path of a
> ballistic projectile cannot be specified by it location, omitting its
velocity.
> But to include rates means an implicit introduction of time and continuity
of
> OMs.  This implies that OMs form causal chains and it makes no sense to
talk
> about the same OM being in two different chains.


That's true in an isolated personal universe that is not interacting with an
'outside world'. I could, e.g. take your brain and simulate that on a
computer. The evolution equations for your brain are deterministic, so the
simulation will describe a unique chain of causal links provided you fix the
boundary conditions.

If the personal universe is embedded in another universe (like in our case),
then the evolution equations will be constantly perturbed.




>
> But a lot of the motivation for OMs comes from the brain *not* being
classical;
> from the idea that the brain gets "copied" into Everett's multiple
relative
> states or MWIs.  Decoherence in the brain is very much faster than the
> neurochemical processes - that's why it's approximately classical.  So
what is
> going on when QM predicts different OMs?  From Everett's point of view the
> brain must be treated as part of the QM system and it gets "copied" - but
not
> by itself.  Its description must include its entanglement with the quantum
> systems observed.  So it seems that in either case, classical or quantum,
an OM
> as a description of a brain state, has links outside itself.  In the
classical
> case it has casual links in time.  In the QM case it has Hilbert space
links to
> what has been observed.


I agree. But the entangled state of a brain with the rest of the universe in
the MWI corresponds to an ensemble of different worlds such that in each
member of the ensemble the brain is in some definite state.


>
> >So, I see no problem with Hal's way of thinking about OMs
> >
> >
> >Observers are can be thought of as their own descriptions and thus
universes
> >in their own right. Observer moments are observers in particular states
i.e.
> >their ''personal'' universe being in a certain state. The causal relation
> >between successive states is already defined when we specify which
observer
> >we are talking about. i.e., we have already specified the laws of physics
> >for the personal universe of an observer which defines the observer.
> >Specifying the initial state of the personal universes thus suffices.
>
> That would hold for a classical brain in a classical universe.  But does
it in
> a QM universe?  I see a tension between the idea of "personal universe"
and
> quantum entanglement.

I don't see problems here. If you assume that our universe is described by
some fundamental laws of physics then those laws of physics also describe
our brains. The way a particular brain works is thus fixed. This then
defines the personal universe. Entanglement of the brain with another system
can only happen if there are interactions with the outside. Even in the
classic case these intercations make the evolution of the personal universe
nondeterministic.



Saibal

-
Defeat Spammers by launching DDoS attacks on Spam-Websites:
http://www.hillscapital.com/antispam/



Re: Observer-Moment Measure from Universe Measure

2005-06-10 Thread Saibal Mitra

- Original Message - 
From: "Brent Meeker" <[EMAIL PROTECTED]>
To: "Saibal Mitra" <[EMAIL PROTECTED]>
Sent: Wednesday, June 08, 2005 02:23 PM
Subject: RE: Observer-Moment Measure from Universe Measure


>
>
> >-Original Message-
> >From: Saibal Mitra [mailto:[EMAIL PROTECTED]
> >Sent: Wednesday, June 08, 2005 1:16 PM
> >To: Patrick Leahy; Hal Finney; [EMAIL PROTECTED]; [EMAIL PROTECTED]
> >Cc: everything-list@eskimo.com
> >Subject: Re: Observer-Moment Measure from Universe Measure
> >
> >
> >I think one should define an observer moment as the instantaneous
> >description of the human brain. I.e. the minimum amount of information
you
> >need to simulate the brain of a observer. This description changes over
time
> >due to interactions with the environment. Even if there were no
interactions
> >with the environment the description would change, but this change is
fixed
> >by the original description.
>
> That means that, supposing the brain is a classical, the "moment" cannot
be
> defined by a description of values, omitting rates; just as the path of a
> ballistic projectile cannot be specified by it location, omitting its
velocity.
> But to include rates means an implicit introduction of time and continuity
of
> OMs.  This implies that OMs form causal chains and it makes no sense to
talk
> about the same OM being in two different chains.


That's true in an isolated personal universe that is not interacting with an
'outside world'. I could, e.g. take your brain and simulate that on a
computer. The evolution equations for your brain are deterministic, so the
simulation will describe a unique chain of causal links provided you fix the
boundary conditions.

If the personal universe is embedded in another universe (like in our case),
then the evolution equations will be constantly perturbed.




>
> But a lot of the motivation for OMs comes from the brain *not* being
classical;
> from the idea that the brain gets "copied" into Everett's multiple
relative
> states or MWIs.  Decoherence in the brain is very much faster than the
> neurochemical processes - that's why it's approximately classical.  So
what is
> going on when QM predicts different OMs?  From Everett's point of view the
> brain must be treated as part of the QM system and it gets "copied" - but
not
> by itself.  Its description must include its entanglement with the quantum
> systems observed.  So it seems that in either case, classical or quantum,
an OM
> as a description of a brain state, has links outside itself.  In the
classical
> case it has casual links in time.  In the QM case it has Hilbert space
links to
> what has been observed.


I agree. But the entangled state of a brain with the rest of the universe in
the MWI corresponds to an ensemble of different worlds such that in each
member of the ensemble the brain is in some definite state.


>
> >So, I see no problem with Hal's way of thinking about OMs
> >
> >
> >Observers are can be thought of as their own descriptions and thus
universes
> >in their own right. Observer moments are observers in particular states
i.e.
> >their ''personal'' universe being in a certain state. The causal relation
> >between successive states is already defined when we specify which
observer
> >we are talking about. i.e., we have already specified the laws of physics
> >for the personal universe of an observer which defines the observer.
> >Specifying the initial state of the personal universes thus suffices.
>
> That would hold for a classical brain in a classical universe.  But does
it in
> a QM universe?  I see a tension between the idea of "personal universe"
and
> quantum entanglement.

I don't see problems here. If you assume that our universe is described by
some fundamental laws of physics then those laws of physics also describe
our brains. The way a particular brain works is thus fixed. This then
defines the personal universe. Entanglement of the brain with another system
can only happen if there are interactions with the outside. Even in the
classic case these intercations make the evolution of the personal universe
nondeterministic.



Saibal



Re: Observer-Moment Measure from Universe Measure

2005-06-10 Thread Bruno Marchal


Le 09-juin-05, à 23:00, Jonathan Colvin a écrit :


Bruno wrote:

I don't believe in observers, if by "observer" one means to assign
special ontological status to mental states over any other

arrangement

of matter.



I don't believe in matters, if by "matters" one means to
assign special ontological status to some substance, by which
it is mean (Aristotle) anything entirely determined by its parts.


Hehe, the usual response to idealism is to drop a rock onto the 
propounder's
finger, and then ask them if they still do not believe in material 
objects.



And the usual answer of the idealist is that they dream sometimes on 
rock dropped on their fingers. That proves nothing. With comp you can 
invoke the matrix or Galouye's Simulacron III.







This is similar to the objection to the classic

interpretation of QM,

whereby an "observation" is required to collapse the WF (how do you
define "observer"?..a rock?..a chicken?..a person?).



Yes, but Everett did succeed his explanation of the apparent collapse
by defining an observer by "just"  classical memory machine.


But the point is that observation is not central to Everett's theory 
at all;
observation is wholly peripheral, and is only discussed insofar as why 
it

*appears* that a collapse happens.



I have argued at length that this is a weak point in Everett. The idea 
is that once you postulate comp like Everett does, then you need to 
explain why you take only the quantum computation into account.










Perhaps you could try to tell me what do you mean by "matter?"


Something that kicks back (has an effect on the universe).



I don't take the word "universe" as granted, still less physicalist 
type of universe. Actually I search an explanation of just that. With 
comp, my point is that universe emerges from all (immaterial, 
mathematical) computations. Arithmetical truth alone can be shown to be 
a vast "video game" or simulacron ... Perhaps you could study a little 
bit of theoretical computer science. They are many conuter-intuitive 
results which could help to think that what I say is at least pausible.




Note that this
excludes "epiphenomena" such as qualia or some interpretions of
consciousness, since it appears that the universe would keep running 
exactly

the same way without them.



All what I say is that if you are right on this point, then comp is 
false. (Or there is an error in my thesis, but this I am always 
assuming by default).


Bruno

http://iridia.ulb.ac.be/~marchal/




RE: Observer-Moment Measure from Universe Measure

2005-06-09 Thread Jonathan Colvin
Bruno wrote:
> > I don't believe in observers, if by "observer" one means to assign 
> > special ontological status to mental states over any other 
> arrangement 
> > of matter.

> I don't believe in matters, if by "matters" one means to 
> assign special ontological status to some substance, by which 
> it is mean (Aristotle) anything entirely determined by its parts.

Hehe, the usual response to idealism is to drop a rock onto the propounder's
finger, and then ask them if they still do not believe in material objects.
 
> > This is similar to the objection to the classic 
> interpretation of QM, 
> > whereby an "observation" is required to collapse the WF (how do you 
> > define "observer"?..a rock?..a chicken?..a person?).
> 
> 
> Yes, but Everett did succeed his explanation of the apparent collapse 
> by defining an observer by "just"  classical memory machine.

But the point is that observation is not central to Everett's theory at all;
observation is wholly peripheral, and is only discussed insofar as why it
*appears* that a collapse happens.




> Perhaps you could try to tell me what do you mean by "matter?"

Something that kicks back (has an effect on the universe). Note that this
excludes "epiphenomena" such as qualia or some interpretions of
consciousness, since it appears that the universe would keep running exactly
the same way without them.

Jonathan Colvin



Re: Observer-Moment Measure from Universe Measure

2005-06-09 Thread Bruno Marchal


Le 09-juin-05, à 01:19, Jonathan Colvin a écrit :


I don't believe in observers, if by "observer" one means to assign 
special
ontological status to mental states over any other arrangement of 
matter.




I don't believe in matters, if by "matters" one means to assign special 
ontological status to some substance, by which it is mean (Aristotle) 
anything entirely determined by its parts.





This is similar to the objection to the classic interpretation of QM,
whereby an "observation" is required to collapse the WF (how do you 
define

"observer"?..a rock?..a chicken?..a person?).



Yes, but Everett did succeed his explanation of the apparent collapse 
by defining an observer by "just"  classical memory machine.






But this was in response to a comment that "it was time to get serious 
about
observer-moments". An observer is such a poorly defined and nebulous 
thing

that I don't think one can get serious about it.




My definition is that an observer is a universal (Turing) machine. With 
Church's thesis we can drop the "Turing" qualification.
Actually an observer is a little more. It is a sufficiently "rich" 
universal machine.
To be utterly precise (like in my thesis) an observer is a lobian 
machine, by which I mean any machine which is able to prove "ExP(x) -> 
Provable("ExP(x))" for any decidable predicate P(x). ExP(x) means 
there is a natural number x such that P(x), and "provable" is the 
provability predicate studied by Godel, Lob and many others.
But then I need to explain more on the provability logic to explain the 
nuances between the scientist machine, the knowing machine, the 
observing machine, etc. You can look at my sane paper for an overview.






I'd note that your
definition is close to being circular.."an observer is something
sufficiently similar to me that I might think I could have been it". 
But how
do we decide what is "sufficient"? The qualities you list 
(consciousness,

perception etc) are themselves poorly defined or undefinable.



Consciousness can be considered as a first person view of the result of 
an automatic bet on the existence of a model (in the logician sense) of 
oneself. From this we can explain why "consciousness" is not 
representable in the language of a machine. And consciousness get a 
role: self-speeding up oneself relatively to our most probable 
computational histories.

It should develop in all self-moving mechanical entity.

I define variant of "first person view" by applying Theaetetus' 
definition of knowledge (and "popperian" variants) on the Godel 
self-referential provability predicate.


Perhaps you could try to tell me what do you mean by "matter?"

Bruno

http://iridia.ulb.ac.be/~marchal/




RE: Observer-Moment Measure from Universe Measure

2005-06-08 Thread Jonathan Colvin
Hal Finney wrote:
>Jonathan Colvin writes:
>> There's a question begging to be asked, which is (predictably I 
>> suppose, for a qualia-denyer such as myself), what makes you think 
>> there is such a thing as an "essence of an experience"? I'd suggest 
>> there is no such "thing" as an observer-moment. I'm happy with using 
>> the concept as a tag of sorts when discussing observer selection 
>> issues, but I think reifying it is likely a mistake, and goes 
>> considerably beyond Strong AI into a full Cartesian dualism. Is it 
>> generally accepted here on this list that a 
>substrate-independent thing called an "observer moment" exists?
>
>Here's how I attempted to define observer moment a few years ago:
>
>Observer - A subsystem of the multiverse with qualities 
>sufficiently similar to those which are common among human 
>beings that we consider it meaningful that we might have been 
>or might be that subsystem.
>These qualities include consciousness, perception of a flow of 
>time, and continuity of identity.
>
>Observer-moment - An instant of perception by an observer.  An 
>observer's sense of the flow of time allows its experience to 
>be divided into units so small that no perceptible change in 
>consciousness is possible in those intervals.  Each such unit 
>of time for a particular observer is an observer-moment.
>
>So if you don't believe in observer-moments, do you also not 
>believe in observers?  Or is it the -moment that causes problems?

I don't believe in observers, if by "observer" one means to assign special
ontological status to mental states over any other arrangement of matter.
This is similar to the objection to the classic interpretation of QM,
whereby an "observation" is required to collapse the WF (how do you define
"observer"?..a rock?..a chicken?..a person?). 

But this was in response to a comment that "it was time to get serious about
observer-moments". An observer is such a poorly defined and nebulous thing
that I don't think one can get serious about it. I'd note that your
definition is close to being circular.."an observer is something
sufficiently similar to me that I might think I could have been it". But how
do we decide what is "sufficient"? The qualities you list (consciousness,
perception etc) are themselves poorly defined or undefinable. We end up with
"an observer is an observer if I think it is an observer"; which is a bit
circular IMHO.

Jonathan Colvin



RE: Observer-Moment Measure from Universe Measure

2005-06-08 Thread Brent Meeker


>-Original Message-
>From: "Hal Finney" [mailto:[EMAIL PROTECTED]
>Sent: Wednesday, June 08, 2005 6:11 PM
>To: everything-list@eskimo.com
>Subject: RE: Observer-Moment Measure from Universe Measure
>
>
>Brent Meeker writes:
>> But the problem I see is that we don't know with certainity the
>present moment
>> either.  I have thoughts and perceptions in a stream, these have finite
>> durations (on the order of hundreds of milliseconds) that overlap
>one another.
>> When you say we know a present moment you are introspecting a memory of what
>> just happened and I think it likely that you are just confabulating that you
>> not only read the above line but that you were *aware of reading it* at the
>> time.
>
>So what do you know?  What would you use as a starting point in a
>philosophical exploration?  Do you assume the world is real?  That it
>is inconceivable that you are living in a simulation?  Do you assume
>that your memories are correct?
>
>Or would you go in the other direction and say that it is possible that
>you are not conscious, perhaps that you don't even exist?
>
>It seems to me that we have to choose something between assuming that all
>our memories are real and the world is exactly as it seems (which is too
>much); or assuming that we might not exist (which is too little).  The OM
>seems to me to fit the bill as far as what is the right thing to assume.
>
>What would you suggest as an alternative?
>
>Hal Finney

I suggest we take thoughts (not assuming a thinker) as evidence - but not as
fundamental in the sense of incorrigble.  For example, there is seeing of words
on my computer screen at this time (awkward in English to avoid saying "I
see..").  But perceptual evidence must be fitted with other evidence
(necessarily from memory) to support a theory of the world, including our
existence in it.  In a metaphor, experiences are like the clues in a crossword
puzzle - how we intepret them must fit them together to complete the puzzle.
In fact I think this is where common-sense and science come from - except that
evolution already provided us with some modes of perception and some categories
of thought (c.f. Singer's "How the Mind Works").

Whatever we think we know amounts to a model or theory about "reality".  It
seems to me that the object of these models is to explain and predict what we
experience.  But if we take our experiences as fundamental what are we going to
do - explain "reality" in terms of them?  I can see this as a project similar
to Bruno's, Experiences->Common-sense->Science->Experiences, where each "->"
corresponds to creating a model.

Brent Meeker



RE: Observer-Moment Measure from Universe Measure

2005-06-08 Thread "Hal Finney"
Brent Meeker writes:
> But the problem I see is that we don't know with certainity the present moment
> either.  I have thoughts and perceptions in a stream, these have finite
> durations (on the order of hundreds of milliseconds) that overlap one another.
> When you say we know a present moment you are introspecting a memory of what
> just happened and I think it likely that you are just confabulating that you
> not only read the above line but that you were *aware of reading it* at the
> time.

So what do you know?  What would you use as a starting point in a
philosophical exploration?  Do you assume the world is real?  That it
is inconceivable that you are living in a simulation?  Do you assume
that your memories are correct?

Or would you go in the other direction and say that it is possible that
you are not conscious, perhaps that you don't even exist?

It seems to me that we have to choose something between assuming that all
our memories are real and the world is exactly as it seems (which is too
much); or assuming that we might not exist (which is too little).  The OM
seems to me to fit the bill as far as what is the right thing to assume.

What would you suggest as an alternative?

Hal Finney



RE: Observer-Moment Measure from Universe Measure

2005-06-08 Thread "Hal Finney"
The motivation for the observer-moment concept is that it is intended
to capture the bare minimum that we know to be true about the world.
We don't know that our pasts are real.  They could be imagined,
synthesized, or faked.  We may have been created one second ago and be
destroyed one second in the future.

To start with the idea that we are observers, with a given history and
past timeline, is to assume more than is in evidence.  For a valid
philosophical inquiry, we need to distinguish what we know from what we
assume.

All we know is the present moment.  We assume a history to explain it,
but we must at least consider the possibility that the history is wrong.

The program I outlined at the start of this thread provides an
in-principle way of calculating how much contribution "fake" versions
of an observer-moment (such as brains in vats, or living in The Matrix)
make versus "real" versions (where conventional reality is as it seems).
Of course it is not tractable in practice; you'd have to simulate every
possible universe and see which ones instantiated a particular OM.

But the point is that we must consider the possibility that our pasts
are not real.  And in truth, scientific experiments have shown that many
of our memories are partially incorrect or even entirely fabricated.
All that we know is the present moment.  It is the raw content of our
experience as observers and it is what we must explain.

Hal Finney



RE: Observer-Moment Measure from Universe Measure

2005-06-08 Thread Stathis Papaioannou

Paddy Leahy wrote:

[quoting Hal Finney]

Here's how I attempted to define observer moment a few years ago:

Observer - A subsystem of the multiverse with qualities sufficiently
similar to those which are common among human beings that we consider
it meaningful that we might have been or might be that subsystem.
These qualities include consciousness, perception of a flow of time,
and continuity of identity.

Observer-moment - An instant of perception by an observer.  An observer's
sense of the flow of time allows its experience to be divided into
units so small that no perceptible change in consciousness is possible
in those intervals.  Each such unit of time for a particular observer
is an observer-moment.


So if you don't believe in observer-moments, do you also not believe
in observers?  Or is it the -moment that causes problems?



Obviously, its the -moment. I'm pleased to see that Jonathan and Brent have 
the same problem with the concept that I do.


Being an observer is a process. Slicing it into moments is OK 
mathematically, where a "moment" corresponds to a calculus dt (and hence is 
neither a particular length of time nor an instant). But to regard the 
"observer-state" at a particular moment as an isolated entity which is 
self-aware makes as much sense as regarding individual horizontal slices 
through a brain as being self-aware. It is the causal relation between 
successive brain states (incorporating incoming sense data) which 
constitutes intelligence, and self-awareness is just an epiphenomenon on 
top of intelligence, i.e. I would not agree that anything can be self-aware 
but have no intelligence.


You're making it far more complicated than it needs to be. An observer 
moment is just a period of conscious experience. Usually it is taken to be 
the shortest possible period, which for a human is somewhere between 100 and 
500 ms, but there is no reason not to discuss observer minutes, hours or 
whatever seems appropriate to the context. The "real" entity is the 
observer, not the observer moment, but it sometimes helps to divide up the 
observer's experience into time slices just as it is helpful to divide up 
the day into hours, minutes and seconds. The division does not imply any 
theory about how the brain actually gives rise to conscious experience, any 
more than clocks imply any theory about how the planet rotates on its axis.


--Stathis Papaioannou

_
REALESTATE: biggest buy/rent/share listings   
http://ninemsn.realestate.com.au




Re: Observer-Moment Measure from Universe Measure

2005-06-08 Thread Saibal Mitra
I think one should define an observer moment as the instantaneous
description of the human brain. I.e. the minimum amount of information you
need to simulate the brain of a observer. This description changes over time
due to interactions with the environment. Even if there were no interactions
with the environment the description would change, but this change is fixed
by the original description.



So, I see no problem with Hal's way of thinking about OMs


Observers are can be thought of as their own descriptions and thus universes
in their own right. Observer moments are observers in particular states i.e.
their ''personal'' universe being in a certain state. The causal relation
between successive states is already defined when we specify which observer
we are talking about. i.e., we have already specified the laws of physics
for the personal universe of an observer which defines the observer.
Specifying the initial state of the personal universes thus suffices.



Saibal


- Original Message - 
From: "Patrick Leahy" <[EMAIL PROTECTED]>
To: "Hal Finney" <[EMAIL PROTECTED]>
Cc: 
Sent: Wednesday, June 08, 2005 01:04 PM
Subject: RE: Observer-Moment Measure from Universe Measure


>
> On Tue, 7 Jun 2005, Hal Finney wrote:
>
> > Jonathan Colvin writes:
> >> There's a question begging to be asked, which is (predictably I
suppose, for
> >> a qualia-denyer such as myself), what makes you think there is such a
thing
> >> as an "essence of an experience"? I'd suggest there is no such "thing"
as an
> >> observer-moment. I'm happy with using the concept as a tag of sorts
when
> >> discussing observer selection issues, but I think reifying it is likely
a
> >> mistake, and goes considerably beyond Strong AI into a full Cartesian
> >> dualism. Is it generally accepted here on this list that a
> >> substrate-independent thing called an "observer moment" exists?
> >
> > Here's how I attempted to define observer moment a few years ago:
> >
> > Observer - A subsystem of the multiverse with qualities sufficiently
> > similar to those which are common among human beings that we consider
> > it meaningful that we might have been or might be that subsystem.
> > These qualities include consciousness, perception of a flow of time,
> > and continuity of identity.
> >
> > Observer-moment - An instant of perception by an observer.  An
observer's
> > sense of the flow of time allows its experience to be divided into
> > units so small that no perceptible change in consciousness is possible
> > in those intervals.  Each such unit of time for a particular observer
> > is an observer-moment.
> >
> >
> > So if you don't believe in observer-moments, do you also not believe
> > in observers?  Or is it the -moment that causes problems?
> >
>
> Obviously, its the -moment. I'm pleased to see that Jonathan and Brent
> have the same problem with the concept that I do.
>
> Being an observer is a process. Slicing it into moments is OK
> mathematically, where a "moment" corresponds to a calculus dt (and hence
> is neither a particular length of time nor an instant). But to regard the
> "observer-state" at a particular moment as an isolated entity which is
> self-aware makes as much sense as regarding individual horizontal slices
> through a brain as being self-aware. It is the causal relation between
> successive brain states (incorporating incoming sense data) which
> constitutes intelligence, and self-awareness is just an epiphenomenon on
> top of intelligence, i.e. I would not agree that anything can be
> self-aware but have no intelligence.
>
> Paddy Leahy
>



RE: Observer-Moment Measure from Universe Measure

2005-06-08 Thread Stathis Papaioannou

Jonathan Colvin writes:

There's a question begging to be asked, which is (predictably I suppose, 
for

a qualia-denyer such as myself), what makes you think there is such a thing
as an "essence of an experience"? I'd suggest there is no such "thing" as 
an

observer-moment. I'm happy with using the concept as a tag of sorts when
discussing observer selection issues, but I think reifying it is likely a
mistake, and goes considerably beyond Strong AI into a full Cartesian
dualism. Is it generally accepted here on this list that a
substrate-independent thing called an "observer moment" exists?


I don't see why you make a big deal out of observer moments. You observe 
something, so that's an observer moment; then you observe something else, 
and that's another observer moment; and so on. There is no implied theory 
about what brings about these OM's, how long a moment is, whether the OM's 
can in any sense have an existence separate from the substrate they are 
implemented on, whether a brain is necessary or a computer will do, whether 
two different OM's belonging to the same observer can each be implemented on 
different hardware, etc. These may be worthwhile questions to ask, and the 
OM concept may help in the process of trying to find an answer, but the 
concept itself does not constitute or imply a theory.


--Stathis Papaioannou

_
REALESTATE: biggest buy/rent/share listings   
http://ninemsn.realestate.com.au




RE: Observer-Moment Measure from Universe Measure

2005-06-08 Thread Patrick Leahy


On Tue, 7 Jun 2005, Hal Finney wrote:


Jonathan Colvin writes:

There's a question begging to be asked, which is (predictably I suppose, for
a qualia-denyer such as myself), what makes you think there is such a thing
as an "essence of an experience"? I'd suggest there is no such "thing" as an
observer-moment. I'm happy with using the concept as a tag of sorts when
discussing observer selection issues, but I think reifying it is likely a
mistake, and goes considerably beyond Strong AI into a full Cartesian
dualism. Is it generally accepted here on this list that a
substrate-independent thing called an "observer moment" exists?


Here's how I attempted to define observer moment a few years ago:

Observer - A subsystem of the multiverse with qualities sufficiently
similar to those which are common among human beings that we consider
it meaningful that we might have been or might be that subsystem.
These qualities include consciousness, perception of a flow of time,
and continuity of identity.

Observer-moment - An instant of perception by an observer.  An observer's
sense of the flow of time allows its experience to be divided into
units so small that no perceptible change in consciousness is possible
in those intervals.  Each such unit of time for a particular observer
is an observer-moment.


So if you don't believe in observer-moments, do you also not believe
in observers?  Or is it the -moment that causes problems?



Obviously, its the -moment. I'm pleased to see that Jonathan and Brent 
have the same problem with the concept that I do.


Being an observer is a process. Slicing it into moments is OK 
mathematically, where a "moment" corresponds to a calculus dt (and hence 
is neither a particular length of time nor an instant). But to regard the 
"observer-state" at a particular moment as an isolated entity which is 
self-aware makes as much sense as regarding individual horizontal slices 
through a brain as being self-aware. It is the causal relation between 
successive brain states (incorporating incoming sense data) which 
constitutes intelligence, and self-awareness is just an epiphenomenon on 
top of intelligence, i.e. I would not agree that anything can be 
self-aware but have no intelligence.


Paddy Leahy



Re: Observer-Moment Measure from Universe Measure

2005-06-08 Thread Bruno Marchal


Le 08-juin-05, à 07:51, Jonathan Colvin a écrit :


Hal Finney wrote:

To apply Wei's method, first we need to get serious about what
is an OM.
We need a formal model and description of a particular OM.
Consider, for example, someone's brain when he is having a
particular experience.  He is eating chocolate ice cream while
listening to Beethoven's 5th symphony, on his 30th birthday.
Imagine that we could scan his brain with advanced technology
and record his neural activity.  Imagine further that with the
aid of an advanced brain model we are able to prune out the
unnecessary information and distill this to the essence of the
experience.  We come up with a pattern that represents that
observer moment.  Any system which instantiates that pattern
genuinely creates an experience of that observer moment.  This
pattern is something that can be specified, recorded and
written down in some form.  It probably involves a huge volume of
data.


Sorry for the delay in response, but eskimo started bouncing mail from 
my

other smtp for some unknown reason.

There's a question begging to be asked, which is (predictably I 
suppose, for
a qualia-denyer such as myself), what makes you think there is such a 
thing
as an "essence of an experience"? I'd suggest there is no such "thing" 
as an
observer-moment. I'm happy with using the concept as a tag of sorts 
when
discussing observer selection issues, but I think reifying it is 
likely a

mistake, and goes considerably beyond Strong AI into a full Cartesian
dualism.


Not at all. You get dualism only because *you* are reifying 
metaphysical notion like substantial matter, time etc.





 Is it generally accepted here on this list that a
substrate-independent thing called an "observer moment" exists?



To be sure I have problem with the notion of observer moments, or more 
precisely with the idea that observer-moments can be taken as 
primitive.
With comp (which is stronger than strong AI, strictly speaking) it has 
been proved that both 
space-time-energy-matter-sharable-measurable-quantity AND their 
qualitative features emerges from arithmetical truth. Comp implies a 
"neutral monism".


Bruno

http://iridia.ulb.ac.be/~marchal/




RE: Observer-Moment Measure from Universe Measure

2005-06-07 Thread "Hal Finney"
Jonathan Colvin writes:
> There's a question begging to be asked, which is (predictably I suppose, for
> a qualia-denyer such as myself), what makes you think there is such a thing
> as an "essence of an experience"? I'd suggest there is no such "thing" as an
> observer-moment. I'm happy with using the concept as a tag of sorts when
> discussing observer selection issues, but I think reifying it is likely a
> mistake, and goes considerably beyond Strong AI into a full Cartesian
> dualism. Is it generally accepted here on this list that a
> substrate-independent thing called an "observer moment" exists?

Here's how I attempted to define observer moment a few years ago:

Observer - A subsystem of the multiverse with qualities sufficiently
similar to those which are common among human beings that we consider
it meaningful that we might have been or might be that subsystem.
These qualities include consciousness, perception of a flow of time,
and continuity of identity.

Observer-moment - An instant of perception by an observer.  An observer's
sense of the flow of time allows its experience to be divided into
units so small that no perceptible change in consciousness is possible
in those intervals.  Each such unit of time for a particular observer
is an observer-moment.


So if you don't believe in observer-moments, do you also not believe
in observers?  Or is it the -moment that causes problems?

Hal Finney



RE: Observer-Moment Measure from Universe Measure

2005-06-07 Thread Brent Meeker


>-Original Message-
>From: Jonathan Colvin [mailto:[EMAIL PROTECTED]
>Sent: Wednesday, June 08, 2005 5:51 AM
>To: everything-list@eskimo.com
>Subject: RE: Observer-Moment Measure from Universe Measure
>
>
>Hal Finney wrote:
>>To apply Wei's method, first we need to get serious about what
>>is an OM.
>>We need a formal model and description of a particular OM.
>>Consider, for example, someone's brain when he is having a
>>particular experience.  He is eating chocolate ice cream while
>>listening to Beethoven's 5th symphony, on his 30th birthday.
>>Imagine that we could scan his brain with advanced technology
>>and record his neural activity.  Imagine further that with the
>>aid of an advanced brain model we are able to prune out the
>>unnecessary information and distill this to the essence of the
>>experience.  We come up with a pattern that represents that
>>observer moment.  Any system which instantiates that pattern
>>genuinely creates an experience of that observer moment.  This
>>pattern is something that can be specified, recorded and
>>written down in some form.  It probably involves a huge volume of
>>data.
>
>Sorry for the delay in response, but eskimo started bouncing mail from my
>other smtp for some unknown reason.
>
>There's a question begging to be asked, which is (predictably I suppose, for
>a qualia-denyer such as myself), what makes you think there is such a thing
>as an "essence of an experience"? I'd suggest there is no such "thing" as an
>observer-moment. I'm happy with using the concept as a tag of sorts when
>discussing observer selection issues, but I think reifying it is likely a
>mistake, and goes considerably beyond Strong AI into a full Cartesian
>dualism. Is it generally accepted here on this list that a
>substrate-independent thing called an "observer moment" exists?
>
>Jonathan Colvin

I agree.  There seems to be a jump from the Strong AI idea that a brain can be
instantiated in some medium other than neurons (e.g. a computer) to the idea
that the brain has "states" that instantiate "experiences".  Somehow static
patterns get slipped in place of processes.

Brent Meeker



RE: Observer-Moment Measure from Universe Measure

2005-06-07 Thread Jonathan Colvin
Hal Finney wrote:
>To apply Wei's method, first we need to get serious about what 
>is an OM.
>We need a formal model and description of a particular OM.  
>Consider, for example, someone's brain when he is having a 
>particular experience.  He is eating chocolate ice cream while 
>listening to Beethoven's 5th symphony, on his 30th birthday.  
>Imagine that we could scan his brain with advanced technology 
>and record his neural activity.  Imagine further that with the 
>aid of an advanced brain model we are able to prune out the 
>unnecessary information and distill this to the essence of the 
>experience.  We come up with a pattern that represents that 
>observer moment.  Any system which instantiates that pattern 
>genuinely creates an experience of that observer moment.  This 
>pattern is something that can be specified, recorded and 
>written down in some form.  It probably involves a huge volume of
>data.

Sorry for the delay in response, but eskimo started bouncing mail from my
other smtp for some unknown reason.

There's a question begging to be asked, which is (predictably I suppose, for
a qualia-denyer such as myself), what makes you think there is such a thing
as an "essence of an experience"? I'd suggest there is no such "thing" as an
observer-moment. I'm happy with using the concept as a tag of sorts when
discussing observer selection issues, but I think reifying it is likely a
mistake, and goes considerably beyond Strong AI into a full Cartesian
dualism. Is it generally accepted here on this list that a
substrate-independent thing called an "observer moment" exists?

Jonathan Colvin  



Re: Observer-Moment Measure from Universe Measure

2005-06-07 Thread Bruno Marchal

Le 07-juin-05, à 00:31, Brent Meeker a écrit :



BM:
For knowability I take the S4 axioms and rules:

1) axioms:



BX -> X
BX -> BBX
B(X->Y) -> (BX -> BY)

2) Rule:

X  X -> Y X
---   -   (Modus ponens, necessitation)
YBX

But in the interview of the Lobian machine I recover the S4 axioms +
Grz, from
defining "knowing X" by "proving X formally and X true" (I apply the
Theaetetus on
formal provability).

I cannot use Gettier's given that I have no notion of causality to
start with. (Recall
I don't have any physical notion to start with).

Bruno

In that case, how does "true" differ from "provable"?  If it is simply a formal
system, with no facts which can make a proposition true by reference,  then it
seems that there is no separate notion of "true" apart from "provable".


I know you are honest, so I knew you would ask, and I am very glad because you are putting your finger on the most utterly important (admittedly subtle) point which gives sense to the interview of the lobian machine, and which is really no less than Godel incompleteness theorem (or better LOB's theorem, see below).

If B represents provability in sound (correct) formal system it is just plainly true that

BX -> X

In particular if F represents a falsity (your favorite contradiction, P & NOT P,  for instance), then it is again plainly true that

BF -> F

BUT "BF -> F"  is equivalent with NOT BF  (P -> F has the same truth table as NOT P).
So BF -> F is NOT BF, and this is a consistency statement: the false is not provable.
So, given that we are talking about a sound formal system, we know that BF->F is true, but as a consistency statement, we know also, by Godel's second incompleteness theorem, that the system cannot prove its own consistency: BF->F is true but not provable

Put in another way BF->F is true, but B(BF->F) is false. In particular you see that B cannot behave like a knowledge modal operator In particular again BF & F is truly equivalent to BF, but the machine cannot prove that equivalence. 

And so what logic does B obeys to?

Given the apparition of a gap between truth and provability we get two logics, one for what the machine is able to prove about its own B, and one for what is true about that B.
The first is G, and the second is G*. Note that the machine is sound, which means all what the machine proves is correct, so that G is included in G*. But G* is much larger than G. For example G* proves that the machine is consistent -BF. G* proves that the machine cannot prove its own consistency -B(-BF). G* prove that BP <-> (BP & P), but the machine cannot prove it. 

So it makes sense to define "knowledge", for the machine, by a new modal operator Cp (say) defined by Cp = Bp & p. (Theaetetus)  It can be shown that it obeys the S4 axioms, and one more which is the grz formula (the Grzegorczyk formula) which is rather ugly, it is:

B(B(p -> Bp) -> p)-> p

Perhaps ugly, but it should make Stephen happy, because it introduces an irreversible temporality in the possible evolution of the machine knowledge. To show this we should need the Kripke semantics stuff.

But my main point here is that by Godel incompleteness Bp -> p although always true, is not always provable. LOB theorem says exactly when Bp->p is provable, it is provable only when p is provable!  The machine M is closed for the rule:

if M proves Bp -> p then M proves p.

M can prove it!M proves B(Bp -> p) -> Bp

And Solovay will prove that this Lob's formula is enough, along with B(p->q)->(Bp->Bq) to derive the whole discourse of the machine with the modus ponens and the necessitation rule. (that's G). G* has as axioms all the theorems of G, + Bp -> p, and is closed for the modus ponens rule BUT NOT FOR THE NECESSITATION rule

Exercise 1: show that G* would be inconsistent if you add the necessitation rule.
Exercise 2: what was precisely wrong in your comment?

Bruno



appendice:
Taken from my post: http://www.escribe.com/science/theory/m2855.html with [] = B here.

I recall that a formal presentation of G is:

AXIOMS[](p -> q) -> ([]p -> []q) K
[]([]p -> p) -> []p L 


RULES  p p -> qp
 Modus Ponens  ---  Necessitation
q   []p


and G* is

AXIOMSAny theorem of G
[]p -> p

RULES  p p -> q   
 Modus Ponens(only! No Necessitation rule!!!)
q

(Plus some "obvious but tedious" substitution rules)



http://iridia.ulb.ac.be/~marchal/


RE: Observer-Moment Measure from Universe Measure

2005-06-06 Thread Brent Meeker


>-Original Message-
>From: Bruno Marchal [mailto:[EMAIL PROTECTED]
>Sent: Monday, June 06, 2005 12:36 PM
>To: Brent Meeker
>Cc: EverythingList list
>Subject: Re: Observer-Moment Measure from Universe Measure
>
>
>
>Le 06-juin-05, à 01:40, Brent Meeker a écrit :
>
>> What do you take to be the standard definition of "knows"?  Is it "X
>> knows Y"
>> iff "X believes Y is true" and "Y is true"?
>
>That's the one by Theaetetus.
>
>> Or do you include Gettier's
>> amendment, "X knows Y" iff "X believes Y is true" and "Y is true" and
>> "There is
>> a causal chain between the fact that makes Y true and X's belief that
>> Y"?
>
>It could depend of the axiom chosen to describe belief.
>
>For knowability I take the S4 axioms and rules:
>
>1) axioms:
>
>
>
>BX -> X
>BX -> BBX
>B(X->Y) -> (BX -> BY)
>
>2) Rule:
>
>X  X -> Y X
>---   -   (Modus ponens, necessitation)
>  YBX
>
>But in the interview of the Lobian machine I recover the S4 axioms +
>Grz, from
>defining "knowing X" by "proving X formally and X true" (I apply the
>Theaetetus on
>formal provability).
>
>I cannot use Gettier's given that I have no notion of causality to
>start with. (Recall
>I don't have any physical notion to start with).
>
>Bruno

In that case, how does "true" differ from "provable"?  If it is simply a formal
system, with no facts which can make a proposition true by reference,  then it
seems that there is no separate notion of "true" apart from "provable".

Brent Meeker



Re: Observer-Moment Measure from Universe Measure

2005-06-06 Thread "Hal Finney"
Johnathan Corgan writes:
> As I'm sure many on the list are familiar, David Brin's "Kiln People" is 
> an interesting science fiction treatment of similar issues.

It is an interesting story which helps to make some of our philosophical
thought experiments more concrete.  Making copies, destroying them, the
nondeterministic experience of wondering whether you will become the copy
or the original, all are addressed.  However I found much to dislike in
the way Brin answers these questions.  I wrote a review at
http://www.transhumanism.org/index.php/th/more/285/ .  An excerpt:

"I was shocked and disgusted to see that [Brin] presents the golems as
having no human rights whatsoever.  They are property, nothing more.
They have to step to the back of the bus, get out of the way of the
white, excuse me, human massas, put up with whatever humans want to do
to them.  This shocking recreation of the worst abuses of the slavery
era is presented without much explanation by Brin, or much sensitivity
to the horrific history he is echoing..."

Hal Finney



Re: Observer-Moment Measure from Universe Measure

2005-06-06 Thread Johnathan Corgan

Hal Finney wrote:


Imagine facing your copy, perhaps an exact copy whose mind is synchronized
with yours, and seeing a coin flip which will determine which one is
destroyed.  Your measure will be halved.  In a sense it will have no
subjective effect, your thoughts and memories will be preserved in one
of you.  But in another sense you face a 50-50 chance of experiencing that
mysterous effect of instant death.  I think it would be scary.  Logically,
similar reductions of measure should be viewed in the same light.


As I'm sure many on the list are familiar, David Brin's "Kiln People" is 
an interesting science fiction treatment of similar issues.


In this story, a technology exists by which one may copy one's "standing 
wave" (forgive the cheesy pseudo-terminology) into a specially formed 
clay-based body.  These duplicates, or "dittos", have a limited (24 
hour) lifespan before they self-destruct.  Different clay templates are 
manufactured to enhance different parts of the mind's functioning, so 
one can create dittos that are better at abstract thinking, or that have 
more tolerance to menial work, etc.


In this society, people create a variety of dittos on a daily basis to 
conduct their business in the world while they themselves avoid risk or 
stick to the more pleasant things.  The dittos know exactly what to do 
as they are the exact personality and memories of the original up to the 
point of copying.  They have a compulsion to return home prior to their 
self-destruction so their memories can be reintegrated with their 
original. (It wasn't clear, to me anyway, whether this compulsion was 
forced or whether it was the consequence of the dittos understanding 
that they would "die" if they didn't make it back to reintegrate.)


Brin's treatment of this scenario is well worth the read; it's like a 
novel-length thought experiment.  One scene follows the internal 
dialogue of the protagonist as he enters the copying machine, and then 
the individual internal dialogues of his copies.  There is initial 
continuity and then a divergence as each copy "discovers" which one he 
is and thus what he must do for the day.  And of course, each one feels 
like he became that particular copy at random.


Some of the same issues about whether one should "care" about one's 
copies (and whether the copies should care about the original) are 
handled as well.  In this story, though, since the dittos reintegrate 
their memories, they know they will eventually have the memories of the 
other copies, as well as what has happened with the original in the interim.


Neat stuff.  There is a lot more along these lines, wrapped in a 
suspense/murder/mystery storyline (the protagonist is a detective.)  The 
last third of the book gets a little dubious, though, but it is a good 
read overall nonetheless.


-Johnathan



RE: Observer-Moment Measure from Universe Measure

2005-06-06 Thread Stathis Papaioannou

Hal Finney writes:


Stathis Papaioannou writes:
> Hal Finney writes:
> >There are a few unintuitive consequences, though, such as that large
> >instantiations of OMs will have more measure than small ones, and 
likewise
> >slow ones will have more measure than fast ones.  This is because in 
each
> >case the interpretation program can be smaller if it is easier to find 
the
> >OM in the vastness of a universe, and the slower and bigger an OM is 
the
> >easier it is to find.  I am inclined to tentatively accept these 
results.

> >It does imply that the extreme future vision of some transhumanists,
> >to upload themselves to super-fast, super-small computers, may greatly
> >reduce their measure, which would mean that it would be like taking a
> >large chance of dying.
>
> Could someone please explain what will happen to the hapless 
transhumanists
> in their computer when their measure falls to alarmingly low levels? 
Will

> they develop severe headaches, turn transparent like ghosts, or what?

This is a kind of transformation that hasn't been possible in the world
before, so no normal phenomenon will exactly capture what happens.

To a first approximation, if their measure were reduced by 90%, what
would happen subjectively would be the same as if they took steps that
had a 90% chance of killing them, in this model.

Now, objectively this is different because it would require other people
to deal with their deaths.  But subjectively it would be pretty much
the same.

Perhaps a closer approximation could be achieved if they were not only
killed, but somehow everyone else's memory was changed so that no one
remembered them or noticed that they were gone.

Imagine instead the question, what would it be like, subjectively,
to die instantly and without warning?  It's a hard question to answer.
But it is related to the question, what would it be it like to have your
measure suddenly reduced?  You could imagine your larger before-measure
as being represented by your mind being instantiated as many copies.
Then a certain percentage of those copies are instantly killed.  What is
it like subjectively?

To the copies which remain, there is no subjective change.  To the
copies which were killed, perhaps it is like nothing subjectively,
because there is no longer any subject there.  But it is still a change.

I think a reduction of measure would be like a certain percentage of
my instances being instantly killed.  When I imagine what it is like,
I picture myself being one of the unlucky instances.  I stop and never
know I stopped, while other copies go on.

The other night I had a strange dream.  I came into a room and met someone
whom I came to understand was myself.  I was a copy who had been created
a few moments earlier, and he was the original.  There was a switch on
the wall which would instantly destroy the copy, and I was supposed to
push it.  But I hesitated.  My own consciousness would be destroyed.
On the other hand I was supposedly a copy made just moments earlier,
so only a few seconds of memories would be lost, hardly consequential.
Still I had to face that dilemma: what would it feel like to just stop,
instantly?

Nervously, I went ahead and pushed the button, squeezing my eyes shut
and making a kind of mental "flinch" or jerk.  To my surprise, I was
still there, and when I opened my eyes, the other person was gone.
It turned out that he was the copy and I was the original.

Imagine facing your copy, perhaps an exact copy whose mind is synchronized
with yours, and seeing a coin flip which will determine which one is
destroyed.  Your measure will be halved.  In a sense it will have no
subjective effect, your thoughts and memories will be preserved in one
of you.  But in another sense you face a 50-50 chance of experiencing that
mysterous effect of instant death.  I think it would be scary.  Logically,
similar reductions of measure should be viewed in the same light.


Hal,

What I think you're describing is akin to the traditional view of personal 
identity as something firmly attached to a particular animal, computer or 
whatever. The most important insight the observer moment concept offers, to 
my mind, is that the observer effectively dies every moment, and the 
illusion of an individual persisting through time is created by the 
stringing together of appropriately related OM's. I wouldn't even call this 
a theory; I think it is true ipso facto.


Consider an observer experiencing a series of conscious moments OM1, OM2, 
OM3... etc. Just as OM3 is about to start, he is vapourised by a nuclear 
explosion. Assuming for simplicity there are no parallel universes, the 
observer has died. What does "dying" mean in this context? It means that his 
last conscious moment was OM2, and there will be no more. Notice that 
nothing special has "happened" to OM2; it is the same as if he had continued 
living, and it is unaffected by what may or may not follow. Death consists 
in the absence of successors to OM2.

Re: Observer-Moment Measure from Universe Measure

2005-06-06 Thread Bruno Marchal


Le 06-juin-05, à 01:40, Brent Meeker a écrit :

What do you take to be the standard definition of "knows"?  Is it "X 
knows Y"

iff "X believes Y is true" and "Y is true"?


That's the one by Theaetetus.


Or do you include Gettier's
amendment, "X knows Y" iff "X believes Y is true" and "Y is true" and 
"There is
a causal chain between the fact that makes Y true and X's belief that 
Y"?


It could depend of the axiom chosen to describe belief.

For knowability I take the S4 axioms and rules:

1) axioms:



BX -> X
BX -> BBX
B(X->Y) -> (BX -> BY)

2) Rule:

X  X -> Y X
---   -   (Modus ponens, necessitation)
 YBX

But in the interview of the Lobian machine I recover the S4 axioms + 
Grz, from
defining "knowing X" by "proving X formally and X true" (I apply the 
Theaetetus on

formal provability).

I cannot use Gettier's given that I have no notion of causality to 
start with. (Recall

I don't have any physical notion to start with).

Bruno


http://iridia.ulb.ac.be/~marchal/




RE: Observer-Moment Measure from Universe Measure

2005-06-06 Thread "Hal Finney"
Stathis Papaioannou writes:
> Hal Finney writes:
> >There are a few unintuitive consequences, though, such as that large
> >instantiations of OMs will have more measure than small ones, and likewise
> >slow ones will have more measure than fast ones.  This is because in each
> >case the interpretation program can be smaller if it is easier to find the
> >OM in the vastness of a universe, and the slower and bigger an OM is the
> >easier it is to find.  I am inclined to tentatively accept these results.
> >It does imply that the extreme future vision of some transhumanists,
> >to upload themselves to super-fast, super-small computers, may greatly
> >reduce their measure, which would mean that it would be like taking a
> >large chance of dying.
>
> Could someone please explain what will happen to the hapless transhumanists 
> in their computer when their measure falls to alarmingly low levels? Will 
> they develop severe headaches, turn transparent like ghosts, or what?

This is a kind of transformation that hasn't been possible in the world
before, so no normal phenomenon will exactly capture what happens.

To a first approximation, if their measure were reduced by 90%, what
would happen subjectively would be the same as if they took steps that
had a 90% chance of killing them, in this model.

Now, objectively this is different because it would require other people
to deal with their deaths.  But subjectively it would be pretty much
the same.

Perhaps a closer approximation could be achieved if they were not only
killed, but somehow everyone else's memory was changed so that no one
remembered them or noticed that they were gone.

Imagine instead the question, what would it be like, subjectively,
to die instantly and without warning?  It's a hard question to answer.
But it is related to the question, what would it be it like to have your
measure suddenly reduced?  You could imagine your larger before-measure
as being represented by your mind being instantiated as many copies.
Then a certain percentage of those copies are instantly killed.  What is
it like subjectively?

To the copies which remain, there is no subjective change.  To the
copies which were killed, perhaps it is like nothing subjectively,
because there is no longer any subject there.  But it is still a change.

I think a reduction of measure would be like a certain percentage of
my instances being instantly killed.  When I imagine what it is like,
I picture myself being one of the unlucky instances.  I stop and never
know I stopped, while other copies go on.

The other night I had a strange dream.  I came into a room and met someone
whom I came to understand was myself.  I was a copy who had been created
a few moments earlier, and he was the original.  There was a switch on
the wall which would instantly destroy the copy, and I was supposed to
push it.  But I hesitated.  My own consciousness would be destroyed.
On the other hand I was supposedly a copy made just moments earlier,
so only a few seconds of memories would be lost, hardly consequential.
Still I had to face that dilemma: what would it feel like to just stop,
instantly?

Nervously, I went ahead and pushed the button, squeezing my eyes shut
and making a kind of mental "flinch" or jerk.  To my surprise, I was
still there, and when I opened my eyes, the other person was gone.
It turned out that he was the copy and I was the original.

Imagine facing your copy, perhaps an exact copy whose mind is synchronized
with yours, and seeing a coin flip which will determine which one is
destroyed.  Your measure will be halved.  In a sense it will have no
subjective effect, your thoughts and memories will be preserved in one
of you.  But in another sense you face a 50-50 chance of experiencing that
mysterous effect of instant death.  I think it would be scary.  Logically,
similar reductions of measure should be viewed in the same light.

Hal Finney



Re: Observer-Moment Measure from Universe Measure

2005-06-06 Thread Bruno Marchal


Le 05-juin-05, à 17:30, Stephen Paul King a écrit :

FAR AWAY IN THE HEAVENLY ABODE OF THE GREAT GOD INDRA, THERE IS A 
WONDERFUL NET WHICH HAS BEEN HUNG BY SOME CUNNING ARTIFICER IN SUCH A 
MANNER THAT IT STRETCHES OUT INDEFINITELY IN ALL DIRECTIONS. IN 
ACCORDANCE WITH THE EXTRAVAGANT TASTES OF DEITIES, THE ARTIFICER HAS 
HUNG A SINGLE GLITTERING JEWEL AT THE NET'S EVERY NODE, AND SINCE THE 
NET ITSELF IS INFINITE IN DIMENSION, THE JEWELS ARE INFINITE IN 
NUMBER. THERE HANG THE JEWELS, GLITTERING LIKE STARS OF THE FIRST 
MAGNITUDE, A WONDERFUL SIGHT TO BEHOLD. IF WE NOW ARBITRARILY SELECT 
ONE OF THESE JEWELS FOR INSPECTION AND LOOK CLOSELY AT IT, WE WILL 
DISCOVER THAT IN ITS POLISHED SURFACE THERE ARE REFLECTED ALL THE 
OTHER JEWELS IN THE NET, INFINITE IN NUMBER. NOT ONLY THAT, BUT EACH 
OF THE JEWELS REFLECTED IN THIS ONE JEWEL IS ALSO REFLECTING ALL THE 
OTHER JEWELS, SO THAT THE PROCESS OF REFLECTION IS INFINITE

THE AVATAMSAKA SUTRA
FRANCIS H. COOK: HUA-YEN BUDDHISM : THE JEWEL NET OF INDRA 1977
***
   I am suggesting that these "jewels" give us an excellent way to 
think of OMs. If we are to allow for a value K {ranging from 0 to 1} 
to represent the degree to which one "jewel" "reflects" or "is similar 
to" or "implies", it seems that we get a very neat way to span a whole 
lot of logics and math with a simple picture. And, to top it off, we 
have a way to deal with infinite regress and circularity without 
paradox. (BTW, this is what Non-Well founded set theory is trying to 
explain!)


And Lee wrote in the same vain:



As for circular, too bad your theories aren't circular!  They'd
explain more.


"My theories" are full of circular constructions!  But as it is well 
known circular construction can lead to paradoxes or even to frank 
contradictions. Recursion theory, and then theoretical computer science 
have provided founded semantics for most unfounded mathematical 
structure appearing in computer science.
Don't forget I postulate comp which does give some importance to the 
founded notion of bits and numbers. The magic is that bits and numbers 
leads automatically and naturally to non-founded (circular) structure 
with respect to universal machine/environment.


This is illustrated by the last post on combinators, which I have 
introduced in part as an introduction to computer-theoretical circular 
structure. I don't want to use Non-Well-founded set theory (nor any set 
theory), nor category theory because the minimum of logic I use is 
considered as already too abstruse to many. But those are very 
interesting of course.


Note that John Case, one of the master of computer self-reference, 
refers to the INDRA NET to introduce its generalization of Kleene fixed 
point theorem. My whole approach is based on similar circular 
self-reference, but, being programs or sets, mathematicians can use 
them only when they have founded model of it. Look at the combinators: 
it is only when Dana Scott provide founded models that the work on the 
circular combinatory structures explodes in the literature.


Bruno

PS Lee, I will take some time to comment your posts. Thanks for your 
patience.



http://iridia.ulb.ac.be/~marchal/




Re: Observer-Moment Measure from Universe Measure

2005-06-05 Thread Bruno Marchal

Hi Brent,

Le 05-juin-05, à 13:21, Brent Meeker a écrit :





-Original Message-
From: Bruno Marchal [mailto:[EMAIL PROTECTED]
Sent: Sunday, June 05, 2005 7:02 AM
To: "Hal Finney"
Cc: everything-list@eskimo.com
Subject: Re: Observer-Moment Measure from Universe Measure



Le 05-juin-05, à 05:53, Hal Finney a écrit :


Lee Corbin writes:

But in general, what do observer-moments explain? Or what does the
hypothesis concerning them explain?  I just don't get a good feel
that there are any "higher level" phenomena which might be reduced
to observer-moments (I am still very skeptical that all of physics
or math or something could be reduced to them---but if that is
what is meant, I stand corrected). Rather, it always seems like
a number of (other) people are trying to explain observer-moments
as arising from the activity of a Universal Dovetailer, or a
Platonic ensemble of bit strings, or something.


I would say that observer-moments are what need explaining, rather 
than

things that do the explaining.  Or you could say that in a sense they
"explain" our experiences, although I think of them more as *being*
our experiences, moment by moment.  As we agreed:

An observer-moment is really all we have as our primary experience 
of
the world.  The world around us may be fake; we may be in the 
Matrix

or
a brain in a vat.  Even our memories may be fake.  But the fact 
that

we
are having particular experiences at a particular moment cannot be
faked.


Nothing could be truer.




All right. So you both (Hal Finney and Lee Corbin) with the first 
axiom
defining a knower. It is the incorrigibility axiom: let us write Cp 
for

"to know p" (or to be aware of p, or to be conscious of p).
incorrigibility can be stated by:

Cp -> p

Meaning that for any proposition p we have that Cp -> p is true.
The implication arrow "->" is just the classical implication. It has
nothing to do with notions of causality, or deduction or whatever ...
We can define A -> B by  ((not A) or B) or (not (A and not B)) as this
can be verified by truth-table. I recall:

A -> B
1  1  1
1  0  0
0  1  1
0  1  0

OK?


No. To be conscious of p, where p is some proposition, doesn't imply 
that p is

true - one is often mistaken.




You are right. (i *was* supposing p true!)





 It seems to me that the incorrigibility of
experience is just CCp->Cp, i.e. propositions that you seem to 
perceive "p" may
be incorrigble.  Cp->p only works where p isimplicitly is of the form 
Cq.




OK, but this is Loeb theorem and I will use the B instead of C.
I continue to accept Cp -> p for standard knowledge. We don't say say 
"John knew that (a+b)^2 = a^2 + b^2, but he was false" we say ""John 
believed that (a+b)^2 = a^2 + b^2, but he was false" . By definition we 
cannot know something false. It is the standard definition. But you are 
right I should not have used the term "conscious" nor "aware" here!


Thanks for the correction,

Bruno


http://iridia.ulb.ac.be/~marchal/




RE: Observer-Moment Measure from Universe Measure

2005-06-05 Thread Stathis Papaioannou

Hal Finney writes:


There are a few unintuitive consequences, though, such as that large
instantiations of OMs will have more measure than small ones, and likewise
slow ones will have more measure than fast ones.  This is because in each
case the interpretation program can be smaller if it is easier to find the
OM in the vastness of a universe, and the slower and bigger an OM is the
easier it is to find.  I am inclined to tentatively accept these results.
It does imply that the extreme future vision of some transhumanists,
to upload themselves to super-fast, super-small computers, may greatly
reduce their measure, which would mean that it would be like taking a
large chance of dying.


Could someone please explain what will happen to the hapless transhumanists 
in their computer when their measure falls to alarmingly low levels? Will 
they develop severe headaches, turn transparent like ghosts, or what?


--Stathis Papaioannou

_
SEEK: Over 80,000 jobs across all industries at Australia's #1 job site.   
http://ninemsn.seek.com.au?hotmail




RE: (offlist) RE: Observer-Moment Measure from Universe Measure

2005-06-05 Thread Brent Meeker
OOPS! I meant to post it to the list.  I'll now just post this.

Brent

>-Original Message-
>From: Lee Corbin [mailto:[EMAIL PROTECTED]
>Sent: Sunday, June 05, 2005 4:52 PM
>To: Brent Meeker
>Subject: (offlist) RE: Observer-Moment Measure from Universe Measure
>
>
>Hi Brent,
>
>> Of course science arose out of explaining subjective experiences.  The basic
>> theory of science (and common sense) is that there is some mind-indpendent
>> reality out there.  When I see green grass and an object that is
>similar to me
>> and that object says, "I see green grass." then I take that as evidence that
>> the object is person with experiences like me and that there really is green
>> grass.
>
>May I quote you on-list?  I agree with this *almost* entirely,
>(and don't want to waste in a personal communication an essay
>I want to write aimed at Hal, you, and Stephen Paul King.)
>
>Thanks very much, if this would be all right.
>
>> Brent Meeker
>> "Science is just common-sense writ large."
>
>How *very* true.  It is by summoning almost incredible self-restraint
>(upon reading those words) that I don't launch into a long denunciation
>rant diatribe against the doctrine of the scientific method!!
>
>Lee

I'm not sure what you mean by "the scientific method" - the
hypothetico-deductive method?  So far as I know all the methods of science are
just common sense applied carefully and thoroughly.

Brent Meeker




RE: Observer-Moment Measure from Universe Measure

2005-06-05 Thread Lee Corbin
Bruno writes

> All right. So you both (Hal Finney and Lee Corbin) with the first axiom 

Arghh!   My new revelation says that axioms are fine if
you are doing math. But some of us are doing something
here that is entirely separate: philosophy. I love math;
it is my hobby. But axioms and all that shit are not
pertinent to my quests!  Good luck with yours!  That
may be the reason I can't read any of your papers?

> defining a knower. It is the incorrigibility axiom: let us write Cp for 

more about "defining" and "axioms"  ARGH!

> [Hal writes]
> > That is the sense in which I say that observer-moments are primary;
> > they are the most fundamental experience we have of the world.
> > Everything else is only a theory which is built upon the raw existence
> > of observer-moments.
> 
> All right. I guess you agree that this is compatible with the fact that 
> such a theory, built upon the raw existence of OMs, could infer the 
> existence of more primitive objects,  could explain how the "raw 
> existence of OM" emerges from those more primitive objects and explain 
> also how the theory of those more primitive objects emerge from the 
> (only apparently raw, now) observer moments. All this without being 
> circular. OK?

"Built"?  "Emerge"?  Bah, humbug.

As for circular, too bad your theories aren't circular!  They'd
explain more.

Lee



Re: Observer-Moment Measure from Universe Measure

2005-06-05 Thread Stephen Paul King

Dear Hal and Bruno,


- Original Message - 
From: "Bruno Marchal" <[EMAIL PROTECTED]>

To: ""Hal Finney"" <[EMAIL PROTECTED]>
Cc: 
Sent: Sunday, June 05, 2005 3:02 AM
Subject: Re: Observer-Moment Measure from Universe Measure




Le 05-juin-05, à 05:53, Hal Finney a écrit :

snip

That is the sense in which I say that observer-moments are primary;
they are the most fundamental experience we have of the world.
Everything else is only a theory which is built upon the raw existence
of observer-moments.

[BM]
All right. I guess you agree that this is compatible with the fact that 
such a theory, built upon the raw existence of OMs, could infer the 
existence of more primitive objects,  could explain how the "raw existence 
of OM" emerges from those more primitive objects and explain also how the 
theory of those more primitive objects emerge from the (only apparently 
raw, now) observer moments. All this without being circular. OK?


   Could you explain to us how it is necessary that sets of Observer 
Moments must be "well founded" such that properties like "such a theory, 
built upon the raw existence of OMs, could infer the existence of more 
primitive objects" and "All this without being circular."?
   Why do we insist on having an indivisible Atom from which All is 
constructable? Is it not possible that the distinctions (read properties!) 
between one OM and another are merely those that they do not have in common? 
Instead of the idea of an Atom floating in the Void, let us consider the 
idea of Indra's Net:


http://www.heartspace.org/misc/IndraNet.html

***
FAR AWAY IN THE HEAVENLY ABODE OF THE GREAT GOD INDRA, THERE IS A WONDERFUL 
NET WHICH HAS BEEN HUNG BY SOME CUNNING ARTIFICER IN SUCH A MANNER THAT IT 
STRETCHES OUT INDEFINITELY IN ALL DIRECTIONS. IN ACCORDANCE WITH THE 
EXTRAVAGANT TASTES OF DEITIES, THE ARTIFICER HAS HUNG A SINGLE GLITTERING 
JEWEL AT THE NET'S EVERY NODE, AND SINCE THE NET ITSELF IS INFINITE IN 
DIMENSION, THE JEWELS ARE INFINITE IN NUMBER. THERE HANG THE JEWELS, 
GLITTERING LIKE STARS OF THE FIRST MAGNITUDE, A WONDERFUL SIGHT TO BEHOLD. 
IF WE NOW ARBITRARILY SELECT ONE OF THESE JEWELS FOR INSPECTION AND LOOK 
CLOSELY AT IT, WE WILL DISCOVER THAT IN ITS POLISHED SURFACE THERE ARE 
REFLECTED ALL THE OTHER JEWELS IN THE NET, INFINITE IN NUMBER. NOT ONLY 
THAT, BUT EACH OF THE JEWELS REFLECTED IN THIS ONE JEWEL IS ALSO REFLECTING 
ALL THE OTHER JEWELS, SO THAT THE PROCESS OF REFLECTION IS INFINITE

THE AVATAMSAKA SUTRA
FRANCIS H. COOK: HUA-YEN BUDDHISM : THE JEWEL NET OF INDRA 1977
***
   I am suggesting that these "jewels" give us an excellent way to think of 
OMs. If we are to allow for a value K {ranging from 0 to 1} to represent the 
degree to which one "jewel" "reflects" or "is similar to" or "implies", it 
seems that we get a very neat way to span a whole lot of logics and math 
with a simple picture. And, to top it off, we have a way to deal with 
infinite regress and circularity without paradox. (BTW, this is what 
Non-Well founded set theory is trying to explain!)


Stephen

PS, for more info on Indra''s net see: 
http://ccbs.ntu.edu.tw/FULLTEXT/JR-PHIL/ew25326.htm
and on its relation to NWF sets: 
http://dialog.net:85/homepage/autobook.5/refautol.pdf 



Re: Observer-Moment Measure from Universe Measure

2005-06-05 Thread Saibal Mitra

- Original Message - 
From: ""Hal Finney"" <[EMAIL PROTECTED]>
To: 
Sent: Friday, June 03, 2005 08:10 PM
Subject: Observer-Moment Measure from Universe Measure


> To apply Wei's method, first we need to get serious about what is an OM.
> We need a formal model and description of a particular OM.  Consider, for
> example, someone's brain when he is having a particular experience.  He is
> eating chocolate ice cream while listening to Beethoven's 5th symphony,
> on his 30th birthday.  Imagine that we could scan his brain with advanced
> technology and record his neural activity.  Imagine further that with the
> aid of an advanced brain model we are able to prune out the unnecessary
> information and distill this to the essence of the experience.  We come
> up with a pattern that represents that observer moment.  Any system which
> instantiates that pattern genuinely creates an experience of that observer
> moment.  This pattern is something that can be specified, recorded and
> written down in some form.  It probably involves a huge volume of data.
>
> So, now that we have a handle on what a particular OM is, we can more
> reasonably ask whether a universe instantiates it.


Wouldn't it be better to think of OMs as programs just like we think of
universes? If you only look at patterns then you get the problem which you
later mention like crystals that can represent an OM of a person etc. The
patterns one is looking for should be capable of doing computations


If I define OMs as a programs (in a particular computational state), then
that is the same as saying that OMs are universes in particular states. One
can then argue that these universes are very complex and have high measures
and are thus likely to be found embedded in simple, low measure, universes.
Then one can also address the problem of what qualia actually are. They are
'events' that occur in an OM's universe.


In case of persons one can think of the neural network formed by the brain.
The events that take place in the universe defined by the neural network are
the qualia we experience. So, I think that Wei's interpretation program has
to do more than just spot certain patterns localized in time.



Similarly if I simulate the solar system on a pc, then this defines a
universe in which an event could be that jupiter is at a certain position at
a certain time. To 'see' this in terms of the electrons moving through the
transistors one has to first 'see' the program. Seeing the program requires
one to study the way the object interacts with its environment which means
that you have to take it out of the universe and study how it behaves when
you expose it to alternative inputs.



Saibal



Re: Observer-Moment Measure from Universe Measure

2005-06-05 Thread Bruno Marchal


Le 05-juin-05, à 05:53, Hal Finney a écrit :


Lee Corbin writes:

But in general, what do observer-moments explain? Or what does the
hypothesis concerning them explain?  I just don't get a good feel
that there are any "higher level" phenomena which might be reduced
to observer-moments (I am still very skeptical that all of physics
or math or something could be reduced to them---but if that is
what is meant, I stand corrected). Rather, it always seems like
a number of (other) people are trying to explain observer-moments
as arising from the activity of a Universal Dovetailer, or a
Platonic ensemble of bit strings, or something.


I would say that observer-moments are what need explaining, rather than
things that do the explaining.  Or you could say that in a sense they
"explain" our experiences, although I think of them more as *being*
our experiences, moment by moment.  As we agreed:


An observer-moment is really all we have as our primary experience of
the world.  The world around us may be fake; we may be in the Matrix 
or
a brain in a vat.  Even our memories may be fake.  But the fact that 
we
are having particular experiences at a particular moment cannot be 
faked.


Nothing could be truer.




All right. So you both (Hal Finney and Lee Corbin) with the first axiom 
defining a knower. It is the incorrigibility axiom: let us write Cp for 
"to know p" (or to be aware of p, or to be conscious of p). 
incorrigibility can be stated by:


Cp -> p

Meaning that for any proposition p we have that Cp -> p is true.
The implication arrow "->" is just the classical implication. It has 
nothing to do with notions of causality, or deduction or whatever ... 
We can define A -> B by  ((not A) or B) or (not (A and not B)) as this 
can be verified by truth-table. I recall:


A -> B
1  1  1
1  0  0
0  1  1
0  1  0

OK?




That is the sense in which I say that observer-moments are primary;
they are the most fundamental experience we have of the world.
Everything else is only a theory which is built upon the raw existence
of observer-moments.


All right. I guess you agree that this is compatible with the fact that 
such a theory, built upon the raw existence of OMs, could infer the 
existence of more primitive objects,  could explain how the "raw 
existence of OM" emerges from those more primitive objects and explain 
also how the theory of those more primitive objects emerge from the 
(only apparently raw, now) observer moments. All this without being 
circular. OK?


Bruno

http://iridia.ulb.ac.be/~marchal/




RE: Observer-Moment Measure from Universe Measure

2005-06-04 Thread "Hal Finney"
Lee Corbin writes:
> But in general, what do observer-moments explain? Or what does the
> hypothesis concerning them explain?  I just don't get a good feel
> that there are any "higher level" phenomena which might be reduced
> to observer-moments (I am still very skeptical that all of physics
> or math or something could be reduced to them---but if that is 
> what is meant, I stand corrected). Rather, it always seems like
> a number of (other) people are trying to explain observer-moments
> as arising from the activity of a Universal Dovetailer, or a 
> Platonic ensemble of bit strings, or something.

I would say that observer-moments are what need explaining, rather than
things that do the explaining.  Or you could say that in a sense they
"explain" our experiences, although I think of them more as *being*
our experiences, moment by moment.  As we agreed:

> > An observer-moment is really all we have as our primary experience of
> > the world.  The world around us may be fake; we may be in the Matrix or
> > a brain in a vat.  Even our memories may be fake.  But the fact that we
> > are having particular experiences at a particular moment cannot be faked.
>
> Nothing could be truer.

That is the sense in which I say that observer-moments are primary;
they are the most fundamental experience we have of the world.
Everything else is only a theory which is built upon the raw existence
of observer-moments.


> > In terms of measure, Schmidhuber (and possibly Tegmark) provides a means
> > to estimate the measure of a universe.  Consider the fraction of all bit
> > strings that create that universe as its measure.
>
> I think that perhaps I know exactly what is meant; but I'm unwilling
> to take the chance. Let's say that we have a universe U, and now we
> want to find its measure (its share of the mega-multi-Everything
> resources).  So, as you write, we consider all the bit strings
> that create U.  Let's say for concreteness that only five bit strings
> "really exist" in some deep sense:
>
> 010101110100101010011101010110001010110101...
> 10110111010001010111001011010110100101...
> 0010101001110101001110100010011010...
> 1101110100010011010l11011101010011...   
> 1100101110101011101000110100101001...
>
> and then it just so happens that only 2 out of these five actually
> make the universe U manifest. That is, in the innards of 2 of these,
> one finds all the structures that U contains. Am I following so far?

In the Schmidhuber picture, it's not that the strings contain U,
rather the strings are programs which when run on some UTM produce
U as the output.  This corresponds to the concept you mention below,
the Kolmogorov complexity.  KC is based on the length of programs that
output the objects (strings, or universes, or any other information
based entity).  Measure as I am using it is 1/2^KC where KC is the
Kolmogorov complexity of an object.

> > In practice this is roughly 1/2^n where n is the size of the
> > shortest program that outputs that universe.
>
> So each of these universes (each of the five, in my toy example)
> has a certain Kolmogorov complexity?  Each of the five can be
> output by some program?

Yes, I think this is equivalent to my conception, although when I spoke
of bit strings I was thinking of the inputs to the UTM while you are
talking about the outputs.  But the basic idea is the same.

> But is that program infinite or finite?
>
> Argument for finite: normally we want to speak of *short* programs
> and so that seems to indicate the program has a limited size.
> Argument for infinite: dramatically *few* bit strings that are
> infinite in length have just a finite amount of information.
> Our infinite level-one Tegmark universe, for example, probably
> is tiled by Hubble volumes in a non-repeating irregular way so
> that no program could output it.

Now I think we are both talking about the inputs to the UTM.  Should
we consider infinite length inputs?

I don't think it is necessary, for three reasons.  First, due to the
way TM's work, in practice a random tape will only have some specific
number of input bits that ever get used.  The chance of an infinite
number of bits being used is zero.  Second, you could construct tapes
which used an infinite number of bits, but they would be of measure zero
and hence would make no detectable contribution to the actual numeric
predictions of the theory.  Third, there are variants on UTMs which
only accept self-delimiting input tapes that have, in effect, lengths
that are easily determined.  Greg Chaitin's work focuses on the use of
self-delimiting programs to achieve a more precise picture of algorithmic
complexity (which is equivalent to KC).  The lengths of such programs
are inherently finite.  These UTMs are equivalent to all others.

Note that you could, I think, create an infinite universe even using a
finite tape.  I believe that our universe, even if infinite in Tegmark's
level-one sense, could be output by a fi

RE: Observer-Moment Measure from Universe Measure

2005-06-04 Thread Lee Corbin
Hal Finney has provided some intriguing notions and possibly
some very useful explanations. But I would like help in clarifying
even the first several paragraphs, in order to maximize my
investment in the remainder.

But first a few comments; these may be premature, but if so,
the comments should be ignored.

> Some time back Lee Corbin posed the question of which was more
> fundamental: observer-moments or universes?  I would say, with more
> thought, that observer-moments are more fundamental in terms of explaining
> the subjective appearance of what we see, and what we can expect.

But in general, what do observer-moments explain? Or what does the
hypothesis concerning them explain?  I just don't get a good feel
that there are any "higher level" phenomena which might be reduced
to observer-moments (I am still very skeptical that all of physics
or math or something could be reduced to them---but if that is 
what is meant, I stand corrected). Rather, it always seems like
a number of (other) people are trying to explain observer-moments
as arising from the activity of a Universal Dovetailer, or a 
Platonic ensemble of bit strings, or something.

> An observer-moment is really all we have as our primary experience of
> the world.  The world around us may be fake; we may be in the Matrix or
> a brain in a vat.  Even our memories may be fake.  But the fact that we
> are having particular experiences at a particular moment cannot be faked.

Nothing could be truer.

> But the universe is fundamental, in my view, in terms of the ontology,
> the physical reality of the world.  Universes create and contain observers
> who experience observer-moments.  This is the Schmidhuber/Tegmark model...

Yes, but now arises my need for clarification:

> In terms of measure, Schmidhuber (and possibly Tegmark) provides a means
> to estimate the measure of a universe.  Consider the fraction of all bit
> strings that create that universe as its measure.

I think that perhaps I know exactly what is meant; but I'm unwilling
to take the chance. Let's say that we have a universe U, and now we
want to find its measure (its share of the mega-multi-Everything
resources).  So, as you write, we consider all the bit strings
that create U.  Let's say for concreteness that only five bit strings
"really exist" in some deep sense:

010101110100101010011101010110001010110101...
10110111010001010111001011010110100101...
0010101001110101001110100010011010...
1101110100010011010l11011101010011...   
1100101110101011101000110100101001...

and then it just so happens that only 2 out of these five actually
make the universe U manifest. That is, in the innards of 2 of these,
one finds all the structures that U contains. Am I following so far?

> In practice this is roughly 1/2^n where n is the size of the
> shortest program that outputs that universe.

So each of these universes (each of the five, in my toy example)
has a certain Kolmogorov complexity?  Each of the five can be
output by some program?  But is that program infinite or finite?

Argument for finite: normally we want to speak of *short* programs
and so that seems to indicate the program has a limited size.
Argument for infinite: dramatically *few* bit strings that are
infinite in length have just a finite amount of information.
Our infinite level-one Tegmark universe, for example, probably
is tiled by Hubble volumes in a non-repeating irregular way so
that no program could output it.

Thanks,
Lee

> The Tegmark model may allow for similar reasoning,
> applied to mathematical structures rather than computer programs.
> 
> Now, how to get from universe measure to observer-moment (OM) measure?
> This is what I want to write about