Re: White Rabbit vs. Tegmark

2005-06-15 Thread jamikes
. Will catch up hopefully soon. Best wishes John M - Original Message - From: Hal Finney [EMAIL PROTECTED] To: everything-list@eskimo.com Sent: Tuesday, June 14, 2005 7:41 PM Subject: Re: White Rabbit vs. Tegmark

Re: White Rabbit vs. Tegmark

2005-06-14 Thread jamikes
PROTECTED] To: Hal Finney [EMAIL PROTECTED] Cc: everything-list@eskimo.com Sent: Tuesday, May 24, 2005 2:45 AM Subject: Re: White Rabbit vs. Tegmark

Re: White Rabbit vs. Tegmark

2005-06-14 Thread Hal Finney
John Mikes wrote: ... Those posts were accessible (for me) that started with a statement of the writer and not a lot of copies with some reply-lines interjected. I know (and like to use) to copy the phrases to reply to but even in a 2-week archiving it turns sour. After the first 30-40

RE: White Rabbit vs. Tegmark

2005-05-29 Thread Hal Finney
Jonathan Colvin writes: That's rather the million-dollar question, isn't it? But isn't the multiverse limited in what axioms or predicates can be assumed? For instance, can't we assume that in no universe in Platonia can (P AND ~P) be an axiom or predicate? No, I'd say that you could indeed

Re: White Rabbit vs. Tegmark

2005-05-28 Thread Alastair Malcolm
- Original Message - From: Hal Finney [EMAIL PROTECTED] To: everything-list@eskimo.com Sent: 27 May 2005 19:19 Subject: RE: White Rabbit vs. Tegmark . . To summarize, logic is not a property of universes. It is a tool that our minds use to understand the world, including possible

Re: White Rabbit vs. Tegmark

2005-05-28 Thread Bruno Marchal
Le 27-mai-05, à 20:19, Hal Finney a écrit : Brent Meeker writes: I doubt that the concept of logically possible has any absolute meaning. It is relative to which axioms and predicates are assumed. I agree but that is the reason why if we want to talk *about* or to find measure *on*

RE: White Rabbit vs. Tegmark

2005-05-28 Thread Jonathan Colvin
Hal: To summarize, logic is not a property of universes. It is a tool that our minds use to understand the world, including possible universes. We may fail to think clearly or consistently or logically about what can and cannot exist, but that doesn't change the world out there.

RE: White Rabbit vs. Tegmark

2005-05-28 Thread Jonathan Colvin
Brent: I doubt that the concept of logically possible has any absolute meaning. It is relative to which axioms and predicates are assumed. That's rather the million-dollar question, isn't it? But isn't the multiverse limited in what axioms or predicates can be assumed? For instance,

Re: White Rabbit vs. Tegmark

2005-05-28 Thread Stephen Paul King
Hi Jonathan, Should we not expect Platonia to be Complete? Stephen - Original Message - From: Jonathan Colvin [EMAIL PROTECTED] To: 'Everything-List' everything-list@eskimo.com Sent: Saturday, May 28, 2005 1:30 PM Subject: RE: White Rabbit vs. Tegmark Brent: I doubt

RE: White Rabbit vs. Tegmark

2005-05-28 Thread Jonathan Colvin
Stephen: Should we not expect Platonia to be Complete? I'd like to think that it should not be (by Godel?); or that it is not completely self-computable in finite meta-time. Or some such. But that's more of a faith than a theory. Jonathan Colvin Brent: I doubt that the concept of

Re: White Rabbit vs. Tegmark

2005-05-27 Thread Alastair Malcolm
- Original Message - From: Patrick Leahy [EMAIL PROTECTED] To: Brent Meeker [EMAIL PROTECTED] Cc: Everything-List everything-list@eskimo.com Sent: 26 May 2005 19:54 Subject: RE: White Rabbit vs. Tegmark . . . * But the arbitrariness of the measure itself becomes the main argument against

Re: White Rabbit vs. Tegmark

2005-05-27 Thread Bruno Marchal
Le 26-mai-05, à 18:03, Hal Finney a écrit : One problem with the UD is that the probability that an integer is even is not 1/2, and that it is prime is not zero. Probabilities in general will not equal those defined based on limits as in the earlier paragraph. It's not clear which is the

Re: White Rabbit vs. Tegmark

2005-05-27 Thread Hal Finney
Bruno Marchal writes: Le 26-mai-05, à 18:03, Hal Finney a écrit : One problem with the UD is that the probability that an integer is even is not 1/2, and that it is prime is not zero. Probabilities in general will not equal those defined based on limits as in the earlier paragraph.

RE: White Rabbit vs. Tegmark

2005-05-27 Thread Brent Meeker
-Original Message- From: Alastair Malcolm [mailto:[EMAIL PROTECTED] Sent: Friday, May 27, 2005 8:53 AM To: Patrick Leahy Cc: Everything-List Subject: Re: White Rabbit vs. Tegmark - Original Message - From: Patrick Leahy [EMAIL PROTECTED] To: Brent Meeker [EMAIL PROTECTED] Cc

RE: White Rabbit vs. Tegmark

2005-05-27 Thread Hal Finney
Brent Meeker writes: I doubt that the concept of logically possible has any absolute meaning. It is relative to which axioms and predicates are assumed. Not long ago the quantum weirdness of Bell's theorem, or special relativity would have been declared logically impossible. Is it logically

Re: White Rabbit vs. Tegmark

2005-05-27 Thread Benjamin Udell
I don't see what practical difference there is between saying all universes exist and we need to think with logical consistency about the subject and all logically possible universes exist. Whatever the case, a related point might be worth considering: whether logic is the only such invariant

Re: White Rabbit vs. Tegmark

2005-05-26 Thread Alastair Malcolm
- Original Message - From: Patrick Leahy [EMAIL PROTECTED] To: Alastair Malcolm [EMAIL PROTECTED] Cc: EverythingList everything-list@eskimo.com Sent: 24 May 2005 22:10 Subject: Re: White Rabbit vs. Tegmark . [Patrick:] This is very reminiscent of Lewis' argument. Have you read his

Re: White Rabbit vs. Tegmark

2005-05-26 Thread Patrick Leahy
On Thu, 26 May 2005, Alastair Malcolm wrote: An example occurs which might be of help. Let us say that the physics of the universe is such that in the Milky Way galaxy, carbon-based SAS's outnumber silicon-based SAS's by a trillion to one. Wouldn't we say that the inhabitants of that galaxy

Re: White Rabbit vs. Tegmark

2005-05-26 Thread Russell Standish
On Thu, May 26, 2005 at 11:20:35AM +0100, Patrick Leahy wrote: A measure like this works for the continuum but not for the naturals because you can map the continuum onto a finite segment of the real line. In m6511 Russell Standish describes how a measure can be applied to the naturals

Re: White Rabbit vs. Tegmark

2005-05-26 Thread Hal Finney
Paddy Leahy writes: For the continuum you can restore order by specifying a measure which just *defines* what fraction of real numbers between 0 1 you consider to lie in any interval. For instance the obvious uniform measure is that there are the same number between 0.1 and 0.2 as between

RE: White Rabbit vs. Tegmark

2005-05-26 Thread Patrick Leahy
On Thu, 26 May 2005, Brent Meeker wrote: I agree with all you say. But note that the case of finite sets is not really any different. You still have to define a measure. It may seem that there is one, compelling, natural measure - but that's just Laplace's principle of indifference

Re: White Rabbit vs. Tegmark

2005-05-26 Thread Alastair Malcolm
- Original Message - From: Patrick Leahy [EMAIL PROTECTED] To: Alastair Malcolm [EMAIL PROTECTED] Cc: EverythingList everything-list@eskimo.com Sent: 26 May 2005 11:20 Subject: Re: White Rabbit vs. Tegmark On Thu, 26 May 2005, Alastair Malcolm wrote: An example occurs which might

Re: White Rabbit vs. Tegmark

2005-05-26 Thread Russell Standish
On Thu, May 26, 2005 at 07:54:03PM +0100, Patrick Leahy wrote: * Since the White Rabbit^** argument implicitly assumes a measure, as it stands it can't be definitive. * But the arbitrariness of the measure itself becomes the main argument against the everything thesis, since the main

RE: White Rabbit vs. Tegmark

2005-05-25 Thread Patrick Leahy
On Wed, 25 May 2005, Stathis Papaioannou wrote: SNIP Consider these two parallel arguments using a version of the anthropic principle: (a) In the multiverse, those worlds which have physical laws and constants very different to what we are used to may greatly predominate. However, it is no

Re: White Rabbit vs. Tegmark

2005-05-25 Thread Alastair Malcolm
- Original Message - From: Patrick Leahy [EMAIL PROTECTED] To: Alastair Malcolm [EMAIL PROTECTED] Cc: EverythingList everything-list@eskimo.com Sent: 24 May 2005 22:10 Subject: Re: White Rabbit vs. Tegmark . . This is very reminiscent of Lewis' argument. Have you read his book? IIRC he

RE: White Rabbit vs. Tegmark

2005-05-25 Thread Jonathan Colvin
Stathis: I don't know if you can make a sharp distinction between the really weird universes where observers never evolve and the slightly weird ones where talking white rabbits appear now and then. Consider these two parallel arguments using a version of the anthropic principle: (a)

RE: White Rabbit vs. Tegmark

2005-05-25 Thread Lee Corbin
Paddy writes Stathis Papaioannou wrote: (b) In the multiverse, those worlds in which it is a frequent occurrence that the laws of physics are temporarily suspended so that, for example, talking white rabbits materialise out of thin air, may greatly predominate. However, it is no

Re: White Rabbit vs. Tegmark

2005-05-24 Thread Russell Standish
On Mon, May 23, 2005 at 06:03:32PM -0700, Hal Finney wrote: Paddy Leahy writes: Oops, mea culpa. I said that wrong. What I meant was, what is the cardinality of the data needed to specify *one* continuous function of the continuum. E.g. for constant functions it is blatantly aleph-null.

Re: White Rabbit vs. Tegmark

2005-05-24 Thread Bruno Marchal
Remember that Wolfram assumes a 1-1 correspondence between consciousness and physical activity, which, as you, I have refuted (or I pretend I have refuted, if you prefer). the comp hyp predicts physical laws must be as complex as the solution of the measure problem. In that sense, the apparent

Re: White Rabbit vs. Tegmark

2005-05-24 Thread Bruno Marchal
Le 24-mai-05, à 01:10, Patrick Leahy a écrit : On Mon, 23 May 2005, Hal Finney wrote: I've overlooked until now the fact that mathematical physics restricts itself to (almost-everywhere) differentiable functions of the continuum. What is the cardinality of the set of such functions? I

Re: White Rabbit vs. Tegmark

2005-05-24 Thread Bruno Marchal
Le 24-mai-05, à 00:17, Patrick Leahy a écrit : On Mon, 23 May 2005, Bruno Marchal wrote: SNIP> Concerning the white rabbits, I don't see how Tegmark could even address the problem given that it is a measure problem with respect to the many computational histories. I don't even remember if

RE: White Rabbit vs. Tegmark

2005-05-24 Thread Lee Corbin
Russell writes You've got me digging out my copy of Kreyszig Intro to Functional Analysis. It turns out that the set of continuous functions on an interval C[a,b] form a vector space. By application of Zorn's lemma (or equivalently the axiom of choice), every vector space has what is called

RE: White Rabbit vs. Tegmark

2005-05-24 Thread Hal Finney
Lee Corbin writes: Russell writes You've got me digging out my copy of Kreyszig Intro to Functional Analysis. It turns out that the set of continuous functions on an interval C[a,b] form a vector space. By application of Zorn's lemma (or equivalently the axiom of choice), every vector

Re: White Rabbit vs. Tegmark

2005-05-24 Thread Alastair Malcolm
Perhaps I can throw in a few thoughts here, partly in the hope I may learn something from possible replies (or lack thereof!). - Original Message - From: Patrick Leahy [EMAIL PROTECTED] Sent: 23 May 2005 00:03 . . A very similar argument (rubbish universes) was put forward long ago

Re: White Rabbit vs. Tegmark

2005-05-24 Thread Patrick Leahy
On Tue, 24 May 2005, Alastair Malcolm wrote: Perhaps I can throw in a few thoughts here, partly in the hope I may learn something from possible replies (or lack thereof!). - Original Message - From: Patrick Leahy [EMAIL PROTECTED] Sent: 23 May 2005 00:03 . SNIP This is not a

Re: White Rabbit vs. Tegmark

2005-05-23 Thread Bruno Marchal
Le 23-mai-05, à 06:09, Russell Standish a écrit : On Mon, May 23, 2005 at 04:00:39AM +0100, Patrick Leahy wrote: Hmm, my lack of a pure maths background may be getting me into trouble here. What about real numbers? Do you need an infinite axiomatic system to handle them? Because it seems

Re: White Rabbit vs. Tegmark

2005-05-23 Thread Patrick Leahy
On Sun, 22 May 2005, Hal Finney wrote: Regarding the nature of Tegmark's mathematical objects, I found some old discussion on the list, a debate between me and Russell Standish, in which Russell argued that Tegmark's objects should be understood as formal systems, while I claimed that they

Re: White Rabbit vs. Tegmark

2005-05-23 Thread Bruno Marchal
Hi Patrick, Sorry for having been short, especially on those notions for which some background of logic is needed. Unfortunately I have not really the time to explain with all the nuances needed. Nevertheless the fact that reals are simpler to axiomatize than natural numbers should be a

Re: White Rabbit vs. Tegmark

2005-05-23 Thread Patrick Leahy
On Mon, 23 May 2005, Bruno Marchal wrote: SNIP Concerning the white rabbits, I don't see how Tegmark could even address the problem given that it is a measure problem with respect to the many computational histories. I don't even remember if Tegmark is aware of any measure relating the

Re: White Rabbit vs. Tegmark

2005-05-23 Thread Hal Finney
Paddy Leahy writes: Let's suppose with Wei Dai that a measure can be applied to Tegmark's everything. It certainly can to the set of UTM programs as per Schmidhuber and related proposals. Obviously it is possible to assign a measure which solves the White Rabbit problem, such as the UP.

Re: White Rabbit vs. Tegmark

2005-05-23 Thread Russell Standish
On Mon, May 23, 2005 at 11:17:04PM +0100, Patrick Leahy wrote: And another mathematical query for you or anyone on the list: I've overlooked until now the fact that mathematical physics restricts itself to (almost-everywhere) differentiable functions of the continuum. What is the

Re: White Rabbit vs. Tegmark

2005-05-23 Thread Hal Finney
Paddy Leahy writes: Oops, mea culpa. I said that wrong. What I meant was, what is the cardinality of the data needed to specify *one* continuous function of the continuum. E.g. for constant functions it is blatantly aleph-null. Similarly for any function expressible as a finite-length

Re: White Rabbit vs. Tegmark

2005-05-22 Thread aet.radal ssg
Without getting into a long hurrang, I think that Tegmark is correct, at least in part. Briefly, there has to be a reason why these alternate worlds exist. I'm referring to the Everett-Wheeler hypothesis and not just wishful thinking. Granted, if I remember correctly, Tegmark does deal with the

Re: White Rabbit vs. Tegmark

2005-05-22 Thread Russell Standish
On Mon, May 23, 2005 at 12:03:55AM +0100, Patrick Leahy wrote: ... A very similar argument (rubbish universes) was put forward long ago against David Lewis's modal realism, and is discussed in his On the plurality of worlds. As I understand it, Lewis's defence was that there is no measure

Re: White Rabbit vs. Tegmark

2005-05-22 Thread aet.radal ssg
fight, so until I see something about his theory that is simply untenable, I'll let it slide. - Original Message - From: Russell Standish To: Patrick Leahy Subject: Re: White Rabbit vs. Tegmark Date: Mon, 23 May 2005 09:47:22 +1000 On Mon, May 23, 2005 at 12:03:55AM +0100, Patrick

Re: White Rabbit vs. Tegmark

2005-05-22 Thread Patrick Leahy
On Mon, 23 May 2005, Russell Standish wrote: I think most of us concluded that Tegmark's thesis is somewhat ambiguous. One interpretation of it that both myself and Bruno tend to make is that it is the set of finite axiomatic systems (finite sets of axioms, and recusively enumerated

Re: White Rabbit vs. Tegmark

2005-05-22 Thread Hal Finney
Patrick Leahy writes: Sure enough, you came up with my objection years ago, in the form of the White Rabbit paradox. Since usage is a bit vague, I'll briefly re-state it here. The problem is that worlds which are law-like, that is which behave roughly as if there are physical laws but not

Re: White Rabbit vs. Tegmark

2005-05-22 Thread Hal Finney
Regarding the nature of Tegmark's mathematical objects, I found some old discussion on the list, a debate between me and Russell Standish, in which Russell argued that Tegmark's objects should be understood as formal systems, while I claimed that they should be seen more as pure Platonic objects

Re: White Rabbit vs. Tegmark

2005-05-22 Thread Russell Standish
On Mon, May 23, 2005 at 04:00:39AM +0100, Patrick Leahy wrote: Hmm, my lack of a pure maths background may be getting me into trouble here. What about real numbers? Do you need an infinite axiomatic system to handle them? Because it seems to me that your ensemble of digital strings is