Re: Simulating the Schrödinger Equation

2001-10-23 Thread scerir




Therefore from the first person's perspective 
the laws of quantum mechanics are violated.
[Saibal]

This paper (below)might be relevant.
-s.


"Whose Knowledge?"
- N. David Mermin
Sir 
Rudolph Peierls, in a reply to John Bell's last critique 
of the state of our understanding of quantum mechanics, maintained that it is 
easy to give an acceptable account of the physical significance of the quantum 
theory. The key is to recognize that all the density matrix characterizing a 
physical system ever represents is knowledge about that system. In answer to 
Bell's implicit rejoinder "Whose knowledge?" Peierls offered two simple 
consistency conditions that must be satisfied by density matrices that convey 
the knowledge different people might have about one and the same physical 
system: their density matrices must commute and must have a non-zero product. I 
describe a simple counterexample to his first condition, but show that his 
second condition, which holds trivially if the first does, continues to be valid 
in its absence. It is an open question whether any other conditions must be 
imposed. 
http://arxiv.org/abs/quant-ph/0107151



Re: Predictions duplications

2001-10-23 Thread juergen

 From: [EMAIL PROTECTED]:
 [EMAIL PROTECTED] wrote:
   From [EMAIL PROTECTED]:
   [EMAIL PROTECTED] wrote:
M measure:
M(empty string)=1
M(x) = M(x0)+M(x1) nonnegative for all finite x.
   
   This sounds more like a probability distribution than a measure. In
   the set of all descriptions, we only consider infinite length
   bitstrings. Finite length bitstrings are not members. However, we can
   identify finite length bitstrings with subsets of descriptions. The
   empty string corresponds to the full set of all descriptions, so the
   first line M(empty string)=1 implies that the measure is normalisable
   (ie a probability distribution).
  
  Please check out definitions of measure and distribution! 
  Normalisability is not the critical issue.
  
  Clearly: Sum_x M(x) is infinite. So M is not a probability
  distribution. M(x) is just measure of all strings starting with x:
  M(x) = M(x0)+M(x1) = M(x00)+M(x01)+M(x10)+M(x11) = 
 
 For a measure to be normalisable, the sum over a *disjoint* set of
 subsets must be finite. If the set of subsets is not disjoint (ie the
 intersection are not empty) then the sum may well be infinite.
 Bringing this to the case of finite strings. Each finite string is
 actually a subset of the set of infinite strings, each containing the
 same finite prefix. So the string 101010 is actually a subset of 10101
 and so on. The Sum_x M(x), where I assume x ranges over all strings
 will of course be infinite. However, since the set of finite strings
 is not disjoint, this doesn't imply M(x) is unnormalisable.
 Now when you realise that every finite string x is a subset of the empty
 string, it becomes clear that M(x) is normalised to precisely 1.

The point is: prob dists and measures are different things. There is a
good reason for giving them different names. Prob dists assign numbers
to individual objects, not to sets.  Traditional definitions as well as
those for semimeasures in http://www.idsia.ch/~juergen/toesv2/

  Neglecting finite universes means loss of generality though.
  Hence measures mu(x) in the ATOE paper do not neglect finite x: 
  
  mu(empty string)=1
  mu(x) = P(x)+mu(x0)+mu(x1)  (all nonnegative).
  
  And here P is a probability distribution indeed! 
  P(x)0 possible only for x with finite description. 
  
 
 The P(x)0 case above actually breaks the countably subadditive
 property, so mu(x) cannot be called a measure... I'm not entirely sure
 what you're getting at here.

The set of computable universes includes the finite ones which we may 
not ignore. How do they contribute to the measure of all universes?
For convenience introduce a third symbol $ besides 0 and 1. Now what is 
the measure of the set of all universes starting with 00110? It's the sum of
the measure of the set of universes starting with 001101 and
the measure of the set of universes starting with 001100 and
the measure of the single universe 00110$ that stops right after 00110. 
Once there is a $ symbol there won't be another 0 or 1.  
So mu(x) = P(x)+mu(x0)+mu(x1).  

Our favorite example is the universal Turing machine with random inputs.
For finite x: P(x) is the probability that the TM output is x and nothing
but x. mu(x) is something different, namely, the so-called universal measure 
of all strings _starting_ with x.  Again mu(x) = P(x)+mu(x0)+mu(x1).  

Juergen Schmidhuberhttp://www.idsia.ch/~juergen/




Re: ODP: Free will/consciousness/ineffability

2001-10-23 Thread Marchal

Russell Standish wrote:


As I am bound to paraphrase, Free Will is the ability to do somehthing
completely stupid!

Would you accept:

Freedom is the right to deny 2 + 2 = 5.
 (cf. George Orwell torture scene in 1984)
Free Will is the right to say 2 + 2 = 5 
 (cf. Russell Standish) ?


Interpreting freely to deny 2 + 2 = 5 by -[]f (   f = FALSE or 0 = 1)
and to say 2 + 2 = 5 by []f, you get through Orwell + Standish, 
this interpretation of Godel: 

  Freedom makes Free Will consistent.   (-[]f - []f) 

(Or the inconsistency of free will entails no freedom).

I am guessing you give a good definition of free-will, at least for
the non stupid (sound) machines.
For the stupid one (those inconsistent really believing that 2 + 2 = 5 
or
some equivalent proposition) it is not clear if their stupid acts will 
bear 
any witness to free-will.

Perhaps free will is the ability to do something we *bet* as being
completely stupid, and freedom is the ability of *not*
doing that completely stupid thing?

when George Levy said

 Now let's look at observing free will in the self. Do we perceive
 ourselves to be indeterminate in our behavior? Absolutely sometimes.
 When the decision is clear then free will is really not an issue. Free
 will becomes important when the decision factors are close to being
 evenly split. In those cases, before a decision is made, there is no way
 to know what this decision will be unless one makes the decision. If
 someone asked you why did you choose this, you wouldn't be able to say.
 This is free will.

I tend to disagree. When the decision factors are close to being
evenly split, then I cannot choose and let the first circumstance
choose for me. No need of free will. Following Russell I would say that 
free will could perhaps be the ability of choosing what seems to be the 
stupider choice, ... and freedom could perhaps be the ability to reject 
that stupider solution. I should think a little more about that.


Bruno

  








RE: ODP: Free will/consciousness/ineffability

2001-10-23 Thread Charles Goodwin

It seems unlikely that it could be otherwise. Presumably the impulse to make a 
decision has to originate from a lower level,
assuming that consciousness is supported by layers of unconscious processing? However 
the decisions in question were to do with when
to perform a simple action - pressing a key, or something similar. What about 
conscious decisions that are arrived at by evaluating
evidence, weighing possibilities, etc? Presumably they are also supported by 
unconscious layers which know how to evaluate evidence
etc... Surely the feeling of free will comes from us not being aware of these 
underlying processes.

Charles

 -Original Message-
 From: Brent Meeker [mailto:[EMAIL PROTECTED]]
 Sent: Wednesday, 24 October 2001 9:34 a.m.
 To: rwas
 Cc: [EMAIL PROTECTED]
 Subject: Re: ODP: Free will/consciousness/ineffability


 Whatever free will is, it is very doubtful that it depends on
 consciousness.  See Daniel Dennett's dicussion of the Grey
 Walter carousel
 experiment.  This experiment shows (although there is a
 little ambiguity
 left) that free will decisions occure *before* on is
 conscious of them.

 Brent Meeker
   The freedom of the will consists in the fact that future
 actions cannot
 be known now.
   --- Ludwig Wittgenstein





Re: ODP: Free will/consciousness/ineffability

2001-10-23 Thread rwas

Pete Carlton wrote:

 Hi all,
 I've been lurking for months and am continually amazed by the discussions
 going on - I got into this list after branching out from philosophy of
 mind, after something like the GP/UDA (though completely lacking in
 rigor) had surfaced in a discussion I was in about artificial intelligence..

My interest in this channel has more to do with ai and synthetic consciousness
as well. If you like, we could start our own thread.

Robert W.


_
Do You Yahoo!?
Get your free @yahoo.com address at http://mail.yahoo.com




Re: Entropic Dynamics

2001-10-23 Thread Marchal

Saibal Mitra, [EMAIL PROTECTED]


   A new article by Caticha:

  http://xxx.lanl.gov/abs/gr-qc/0109068

  I explore the possibility that the laws of physics might be laws of 
inference rather than laws of nature. What sort of dynamics can one derive 
from well-established rules of inference? Specifically, I ask: Given 
relevant information codified in the initial and the final states, what 
trajectory is the system expected to follow? The answer follows from a 
principle of inference, the principle of maximum entropy, and not from a 
principle of physics. The entropic dynamics derived this way exhibits some 
remarkable formal similarities with other generally covariant theories 
such as general relativity.

I agree that the laws of physics are related with inference. That
paper seems interesting. I keep it until I get more time to read it.
Thanks.  (He used Fisher Information, and I have still some problems
with it, no doubt those problems relie on my lack of understanding
in statistics).

Bruno




RE: ODP: Free will/consciousness/ineffabili

2001-10-23 Thread Charles Goodwin

 -Original Message-
 From: Brent Meeker [mailto:[EMAIL PROTECTED]]
 Sent: Wednesday, 24 October 2001 12:06 p.m.
 To: Charles Goodwin
 Cc: [EMAIL PROTECTED]
 Subject: RE: ODP: Free will/consciousness/ineffabili

 My intuition doesn't tell me whether or not I would have a 'feeling' of
 free will if I were aware of my subconscious decision processes; but it's
 pretty clear that I could be completely un-conscious and still behave with
 'free will'; whatever it is.

My suggestion is that it's lack of knowledge of these subconscious processes which 
gives you a feeling of free will. If you don't
know what a feeling of free will means (hence the quotes?) I'd suggest it's the 
feeling that you reached a decision uninfluenced by
anything external to yourself. However if you could follow all the subconscious 
processes (you couldn't of course, by definition
your consciousness isn't aware of them) then you'd see that what felt like an 
'uninfluenced' decision was actually the result of
past numerous influences, which had caused your brain to have a particular 
configuration.

Yes, presumably you *could* be unconscious and have free will, in the sense that your 
actions couldn't be predicted accurately by
some other agent. (Try to swat a fly and you will see what I mean!)

 What if your subconscious decision processes became known to you *after*
 you had made your decision and 'felt' that free will.  Would you feel
 something different then?

I don't see what you mean. You'd probably feel different from how you felt when you 
made your decision whether you became aware of
the subconscious processes or not. If you DID become aware of the s.p.s it could 
only be as the result of years of laboriously
tracing through neural connections inside some map that someone made of your brain 
while you were making the decision. (And
presumably more years of tracing through previous maps of your brain which showed how 
various events in the past caused it to be
configured the way it was at the time, if you want a FULL understanding.) I'm not sure 
that you could ever become aware of all
this in any realistic sense of the word. Perhaps a super-intelligent alien could 
apprehend the processes in your brain at a glance
and see what was going on, and THEY would feel that your decision was an inevitable 
consequence of how your brain was configured,
but YOU couldn't.

Charles




Re: ODP: Free will/consciousness/ineffability

2001-10-23 Thread Russell Standish

Interesting, although I suspect the interpretation of the ability to
do somehthing completely stupid is more like asserting the truth of
an unprovable statement than asserting the truth of a false
statement. In modal logic, this would be (x  -[]x )  n'est-ce pas?

Note an automaton cannot assert the truth of anything not provable
from its axioms...

Cheers

Marchal wrote:
 
 Russell Standish wrote:
 
 
 As I am bound to paraphrase, Free Will is the ability to do somehthing
 completely stupid!
 
 Would you accept:
 
 Freedom is the right to deny 2 + 2 = 5.
  (cf. George Orwell torture scene in 1984)
 Free Will is the right to say 2 + 2 = 5 
  (cf. Russell Standish) ?
 
 
 Interpreting freely to deny 2 + 2 = 5 by -[]f (   f = FALSE or 0 = 1)
 and to say 2 + 2 = 5 by []f, you get through Orwell + Standish, 
 this interpretation of Godel: 
 
   Freedom makes Free Will consistent.   (-[]f - []f) 
 
 (Or the inconsistency of free will entails no freedom).
 
 I am guessing you give a good definition of free-will, at least for
 the non stupid (sound) machines.
 For the stupid one (those inconsistent really believing that 2 + 2 = 5 
 or
 some equivalent proposition) it is not clear if their stupid acts will 
 bear 
 any witness to free-will.
 
 Perhaps free will is the ability to do something we *bet* as being
 completely stupid, and freedom is the ability of *not*
 doing that completely stupid thing?
 
 when George Levy said
 
  Now let's look at observing free will in the self. Do we perceive
  ourselves to be indeterminate in our behavior? Absolutely sometimes.
  When the decision is clear then free will is really not an issue. Free
  will becomes important when the decision factors are close to being
  evenly split. In those cases, before a decision is made, there is no way
  to know what this decision will be unless one makes the decision. If
  someone asked you why did you choose this, you wouldn't be able to say.
  This is free will.
 
 I tend to disagree. When the decision factors are close to being
 evenly split, then I cannot choose and let the first circumstance
 choose for me. No need of free will. Following Russell I would say that 
 free will could perhaps be the ability of choosing what seems to be the 
 stupider choice, ... and freedom could perhaps be the ability to reject 
 that stupider solution. I should think a little more about that.
 
 
 Bruno
 
   
 
 
 
 
 




Dr. Russell Standish Director
High Performance Computing Support Unit, Phone 9385 6967, 8308 3119 (mobile)
UNSW SYDNEY 2052 Fax   9385 6965, 0425 253119 ()
Australia[EMAIL PROTECTED] 
Room 2075, Red Centrehttp://parallel.hpc.unsw.edu.au/rks
International prefix  +612, Interstate prefix 02