On 2/7/2012 06:11, meekerdb wrote:
On 2/6/2012 9:55 PM, acw wrote:
On 2/7/2012 05:08, meekerdb wrote:
On 2/6/2012 5:37 PM, acw wrote:
On 2/7/2012 00:28, meekerdb wrote:
On 2/6/2012 3:50 PM, acw wrote:
I'm not so sure to term ``body'' is as meaningful if we consider the
extremes which seem possible in COMP. After a digital substitution, a
body could very well be some software running somewhere, on any kind
of substrate, with an arbitrary time-frame/ordering (as long as 1p
coherent), it could even run directly on some abstract machine which
is not part of our universe (such as some machine emulating another
machine which is contained in the UD) - the only thing that the mind
would have in common is that some program is being instantiated
somewhere, somehow. In this more extreme form, I'm not sure I can see
any difference between a substrate that has the label 'physical' and
some UD running in abstract Platonia. If you can show why the
'physical' version would be required or how can someone even tell the
difference between someone living in a 'physical' world vs someone
living in a purely mathematical (Platonic) world which sees the world
from within said structure in Platonia and calls it 'physical'. It
seems that 'physical' is very much what we call the structure in
which
we exist, but that's indexical, and if you claim that only one such
structure exists (such as this universe), then you think COMP is
false
(that is, no digital substitution exists) or that arithmetic is
inconsistent (which we cannot really know, but we can hope)?


Physics is already extremely abstract and mathematical, so it is
really
not a big step to suppose that the fundamental ontology is mathematics
or computation as Bruno, Tegmark, and others have speculated. The big
step is between supposing that somethings happen and some don't versus
everything (in some sense) happens. To say there must be substrate,
some
'ur-stuff', is really just to say that some things have existence (the
ur-stuff) and some don't.

Brent


What do you mean by 'ur-stuff'? Some structure which is more
privileged than others with 'existence'?

Not structure, just 'existence'.

As in, more general than 'structure'? I'm a bit confused about this.
In my opinion, the claim that some things (for example, some
computations) don't happen is incredibly strong. It makes sense for
someone who has only lived in one universe to say that any other
universe doesn't exist because his classical rationality (such as
Russell's teapot, the requirement for a burden of proof) says that we
can't really claim existence for things we don't have direct evidence
for. On the other hand, Occam's razor makes us favor the simplest
possible theories. A theory which explicitly has to deny some
structures or computations from existing is much more complex and
stronger (and thus will be favored less by Occam or its
formalizations).

But Occam's razor is just a rule-of-thumb. A Russell Standish points
out, in the simplest possible theory nothing exists.


Yet something does exist, thus any theory will have to be a
'something'. Some theories (such as Platonia) do give an easy solution
to the 'why'. Occam's razor may be a rule of the thumb, but doesn't
mean it's not valid, it can also be formalized (although, I won't
insist on it, because most formalizations will instantly bias the
winner to some 'everything' theory - for example if the formalization
is towards computable stuff, the bias is toward the UD). Either way,
even ignoring the explicitly stated Occam's razor, when we'll consider
some theory for the physics of our local universe, we'll inevitably
wonder why these particular laws and the typical answers tend to be
either "all possibilities, we're just one of them" or "don't ask" or
"divine magic". You can guess which answer I prefer.
COMP as derived from UDA/MGA already places great constraints on what
the ontology has to be given the assumption that our brains do admit a
digital substitution and such an act is survivable.

Does it? I thought it entailed infinitely many different universes with
physics limited only by the constraint that they be locally computable.


To me it seems that it says that you don't need anything more than the
UD (or arithmetical truth or ...). Even if there was something more, a
Turing-emulable body will never be able to find out. Although, I guess
that's a core part of this debate - would some transfinite stuff in
the ontology be able to affect the measure or continuations of a
machine/brain (assuming COMP)?
Any theory which claims the UD's existence, but limits the laws of
physics to only a single instance of some string theory, with only one
history and one universe and so on is incredibly strong/very complex,
thus shouldn't be favored (by Occam). It also leads to many other
questions such as: why this mathematical structure is granted
existence, but the others are not? and the conflict between mechanism
and materialism as shown in the MGA. To me it seems like privileging
the indexicals, which seems like a popular conservative materialist
position, although I do wonder why it is that popular - it just favors
one "magic" over the other (this structure, my structure is "special",
all the others aren't), thus I'm not so sure it's the most rational
choice possible, despite that being its aim.

Except it favors the 'magic' we see and use over 'magic' that is
inaccessible.

I suppose, although the consequences of COMP are testable.

Maybe. As Bohr said, "Prediction is difficult, especially about the
future." So far comp's predictions have been about the past.


Technically it can be used to make similar predictions about the future as MWI can, although not in a 3p sharable way (just 1p sharable). However, a lot of the interesting ones are not yet doable because we obviously don't yet have a doctor to say "yes" to.
This sort of favoritism is similar to that of Copenhagen (or some
other single timeline versions) vs MWI - one offers a very complex
incomplete view to make it so the only thing it can talk about is what
we see,

I don't see that it's complex or incomplete. It predicts probabilities.
Some things happen and some don't in accord with the predicted
probabilities. Is it really any simpler to say all those other
possibilities happened too - we just can't access them?

Well, Copenhagen doesn't even describe an underlying model, it's just a predictive model, a "don't ask what's going on" model, thus while it will give you correct results, it won't tell you what's really going on. Some interesting writings on why MWI is preferable to CI:
http://lesswrong.com/lw/q6/collapse_postulates/
http://lesswrong.com/lw/q5/quantum_nonrealism/
http://lesswrong.com/lw/q7/if_manyworlds_had_come_first/
http://lesswrong.com/lw/q8/many_worlds_one_best_guess/
while the other gives you a simple view, but it also tells you that
there's more than you can see. Some people seem bothered about this
'more' part, especially if it's not obviously accessible (although I'd
debate this being the case with COMP).

I'm not bothered, but neither am I convinced. The branches of the MWI
are not obviously accessible and in fact they are not accessible at all.
I wouldn't say that rules them out - but it doesn't count in their favor.

Well, obviously you can only access the branches you're in. Just like with COMP, you can only see the structure you're in, not the full trace of the UD. I did however describe a thought experiment (because we obviously don't have a doctor to say "yes" to yet) on how someone could access unusual, but tightly controlled continuations with completely different "local universal laws" than our own in another thread in this mailing list, which is yet another way of testing COMP's consequences (I'm still awaiting Bruno's response to that thread, up to the point that I'm considering writing a shorter version if writing a full answer to it is too much effort.)
Brent



--
You received this message because you are subscribed to the Google Groups 
"Everything List" group.
To post to this group, send email to everything-list@googlegroups.com.
To unsubscribe from this group, send email to 
everything-list+unsubscr...@googlegroups.com.
For more options, visit this group at 
http://groups.google.com/group/everything-list?hl=en.

Reply via email to