RE: Nothing to Explain about 1st Person C!

[Lee Corbin]

Stathis writes

 Lee Corbin writes:
 
  I anticipate that in the future it will, as you say so well,
  be shown that appropriate brain states necessarily lead to
  conscious states, except I also expect that by then the
  meaning of conscious states will be vastly better informed
  and filled-out than today.  In particular, the concept will
  have migrated from a mix of 1st and 3rd person notions, to
  entirely 3rd person notions. I speculate that after this
  occurs, people won't consider the old 1st person notion to
  be of much value (after all, you can't really use it to
  communicate with anyone about anything).
 
 I really can't imagine how you could make consciousness entirely a 3rd 
 person notion, no matter how well it is understood scientifically. Suppose 
 God, noting our sisyphian debate, takes pity on us and reveals that in fact 
 consciousness is just a special kind of recursive computation. He then gives 
 us a dozen lines of C code, explaining that when implemented this 
 computation is the simplest possible conscious process.

Good example.

 OK, from a scientific point of view, we know *everything* about this
 piece of code.

And, let's say further that we have all sorts of descriptions of it,
which make enormous intuitive sense; but only as much as an experienced
electrical engineer has explanation after explanation, and metaphor after
metaphor, with which he understands and can explain electrical phenomena.

 We also know that it is conscious, which is normally a 1st person thing, 
 because God told us.

Yes, but let's say that it also makes sense, i.e., fits in with
the way that we know how the brains of mammals work, etc. (I do
believe I am only fleshing out your hypothesis---very sorry if
I'm damaging it or changing it.)

 But we *still* don't know what it feels like to *be* the code
 implemented on a computer.
 We might be able to guess, perhaps from analogy with our own
 experience, perhaps by running the code in our head; but once
 we start doing either of these things, we are replacing the 3rd 
 person perspective with the 1st person.

Yes.  Doesn't it seem that you want the impossible?  That you want
to be the code and yet remain someone else?

It seems like only by actually *being* that code---having its
emotional reactions, its same impressions of everything---can
you possibly know what it's like... to be the code. This point
was made by someone here before. Namely, that if *you* become
a bat in order to learn what it's like to be a bat, then you
aren't you anymore.

Lee

RE: What do you lose if you simply accept...

[Jonathan Colvin]

Stathis:  Now, I think you 
  will agree (although Jonathan Colvin may not) that despite this 
  excellent understanding of the processes giving rise to human 
  conscious experience, the aliens may still have absolutely no idea 
  what the experience is actually like.
 
  Jonathan Colvin: No, I'd agree that they have no idea what the
experience is 
 like. But 
  this is no more remarkable than the fact that allthough we 
 may have an 
  excellent understanding of photons, we can not travel at 
 the speed of 
  light, or that although we may have an excellent understanding of 
  trees, yet we can not photosynthesize. Neither of these problems 
  seem particularly hard.
 
 
 Bruno: But we can photosynthesize. And we can understand why we 
 cannot travel at the speed of light. All this by using purely 
 3-person description of those phenomena in some theory.
 With consciousness, the range of the debate goes from 
 non-existence to only-existing. The problem is that it seems 
 that an entirely 3-person explanation of the brain-muscles 
 relations evacuates any purpose for consciousness and the 
 1-person. That's not the case with photosynthesis.

You can photosynthesize? I certainly can not (not being a tree). If I had
photosynthetic pigments in my skin, I suppose I could; and if I had rubbery
wings and sharp teeth I'd be a bat (if my aunt had wheels, she'd be a
wagon). I still can not see (intellectually) the problem of consciousness.
Consciousness /qualia, 1st person phenomena, etc, IMHO, being very poorly
defined, and likely non-existing entities, are a precarious pillar to base
any cosmology or metaphysics on. Observer is far superior, and lacks the
taint of dualism.
To borrow a page from Penrose, I see qualia in much the same light as a
shadow. Everyone can agree what a shadow is, point to one, and talk about
them. But a shadow is not a thing. The ancients made much ado about shadows,
ascribing all sorts of metaphysical significance and whatnot to them. I
think it is quite likely that the fuss about consciousness and qualia
resurrects this old mistake. Shadows of the mind, indeed.

Jonathan Colvin

Observables, Measurables, and Detectors

[Lee Corbin]

Patrick Leahy wrote

 To answer [the] initial question: interference effects are not branches. 
 Actually they imply the absence of effective branching.
 
 You don't get branching in time because time is a parameter, not an 
 observable: this means that there is no quantum uncertainty about what the 
 time is. (At least in the non-relativistic theory. Frankly, I don't know 
 how to handle the relativistic case).
 
 You might say: we don't know what time the particle will be detected. Yes, 
 but the theory doesn't consider the detection event as *one thing* with an 
 uncertain time. In the MWI there are many (a continuum) of detection 
 events, each of which happens at a well defined time and each of which 
 starts off its own branch. And the act of detection changes the detector 
 physically, which is to say that its particles are re-arranged. Hence the 
 slogan every measurement is a position measurement.  Of course they are 
 all momentum measurements as well, etc.

It looks as though you advocate a role for each of these:

   observables
   measurements
   detectors

and for all I know

   observers

It seemed to me that MWI allowed me to get away with a considerable
simplification. Gone were observers and even observations. Even
measurements, I discard. (After all, who can say that a measurement
occurs in the middle of a star? And yet things do go on there, all
the time.)

Now *some* of that language perhaps returns when decoherence is
discussed. I mean, I'll grant that *something* significant starts
off a new branch, and so it's okay for it to have a name.  :-)

But here is what I'd like to be able to say:

A new branch starts, or decoherence obtains, or an irreversible
transformation occurs, or a record is made.  They all seem the
same to me. Why not?

My main motivation is to get as far away from Copenhagen as possible,
and so thereby get free of observers and observations, and anything
else that seems to afford some pieces of matter a privileged status.
Do you think that such simplified language leaves out anything important?

Thanks,
Lee

RE: Nothing to Explain about 1st Person C!

[Stathis Papaioannou]

Lee Corbin writes:


 But we *still* don't know what it feels like to *be* the code
 implemented on a computer.
 We might be able to guess, perhaps from analogy with our own
 experience, perhaps by running the code in our head; but once
 we start doing either of these things, we are replacing the 3rd
 person perspective with the 1st person.

Yes.  Doesn't it seem that you want the impossible?  That you want
to be the code and yet remain someone else?

It seems like only by actually *being* that code---having its
emotional reactions, its same impressions of everything---can
you possibly know what it's like... to be the code. This point
was made by someone here before. Namely, that if *you* become
a bat in order to learn what it's like to be a bat, then you
aren't you anymore.


I agree with everything you have said. You have to be the code to know what 
it is like to be the code. And consciousness is the only thing in the 
universe of which this is true.


--Stathis

_
Free wallpapers on Level 9 http://level9.ninemsn.com.au/default.aspx

Re: Observables, Measurables, and Detectors

[Patrick Leahy]

It looks as though you advocate a role for each of these:

  observables
  measurements
  detectors

and for all I know

  observers

It seemed to me that MWI allowed me to get away with a considerable
simplification. Gone were observers and even observations. Even
measurements, I discard. (After all, who can say that a measurement
occurs in the middle of a star? And yet things do go on there, all
the time.)

Now *some* of that language perhaps returns when decoherence is
discussed. I mean, I'll grant that *something* significant starts
off a new branch, and so it's okay for it to have a name.  :-)

But here is what I'd like to be able to say:

A new branch starts, or decoherence obtains, or an irreversible
transformation occurs, or a record is made.  They all seem the
same to me. Why not?

My main motivation is to get as far away from Copenhagen as possible,
and so thereby get free of observers and observations, and anything
else that seems to afford some pieces of matter a privileged status.
Do you think that such simplified language leaves out anything important?



I don't think we disagree much about the physics. The trouble is, the 
physics is even simpler than you suggest. Branching is not something 
special in the theory, it is a macroscopic description that we apply to 
what emerges from the theory.  If you simplify your language too much, all 
that happens is you have to define all those useful approximate terms from

scratch.

Just for fun, here's how it would go:

The framework of QM in the MWI is that

(1) The state of the system (universe) can be represented by a 
time-dependant, normalized vector, say |S, in a Hilbert space.


(2) Time evolution of |S is linear.

That's it! (1) implies that time evolution is also unitary, so the vector 
stays normed. (1) + (2) imply the Schrodinger equation, including the fact 
that the generator of time evolution (Hamiltonian) is a Hermitian 
operator. (2) causes all the trouble.


A full (non-framework) description requires you to (a) specify the Hilbert 
space (b) specify the Hamiltonian (c) specify the initial state. None of 
which are known exactly for the universe. (And in fact for the universe as 
a whole we had better adapt this description to relativity somehow, since 
you can't just take time as a given.)


Now to introduce some more specific terms so we can relate the theory to 
everyday reality.


Observable: In a simple system, the set of values of an observable are 
simply the labels we attach to elements of a basis, i.e. a set of 
orthogonal unit vectors (defining a coordinate system), in Hilbert 
space. We can freely choose any basis we like, but some are more useful 
than others because they relate to the structure and symmetries of the 
Hamiltonian. Let's call a basis {|o} where o is our variable label. The 
set might be finite, denumerable, or continuous, depending on the size of 
the Hilbert space. For convenience, and to make the transition to 
classical physics as seamless as possible, the labels are usually chosen 
to be real numbers.


To put my previous answer to Serafino into this context, note that 
observables (e.g. position) play a very different role in the theory from 
time.


For each basis, we can construct a linear operator on Hilbert-space 
vectors whose eigenvectors are the basis vectors and whose eigenvalues are 
our observable labels. If our labels are real, the operator will be 
Hermitian. With suitable choice of labels, the algebra of some of these 
operators approximately maps onto the algebra of variables in classical 
physics, which explains why classical physics works, and also how QM was 
discovered. (In particular, since the Hamiltonian itself is hermitian it 
has a set of real eigenvalues which we call Energy).


Wave Function: The inner product of a basis vector with the state 
vector, written o|S, is geometrically the length of the projection of 
the state onto that basis vector, and so the cartesian coordinate along 
the axis defined by |o. In conventional QM it is the probability 
amplitude for observing o. If the basis is continuously infinite, as in 
position or momentum, o|S is a continuous function of the real variable 
(observable) o. This is what we call the wave function in o-space. (e.g. 
o = position, or momentum).


Subsystems: In a complex system, we have to be a bit more careful. What 
physicists call observables certainly don't parameterize a complete basis 
for the universe. Such a complete basis would be characterised by a 
complete set of commuting observables. Commuting because their 
characteristic operators commute. In effect, we factorize the Hilbert 
space into subspaces (corresponding to quasi-independent subsystems). 
Practical observables correspond to bases on some subspace.


Branching: In *some* bases of sufficiently complex systems (appropriate 
basis and needed complexity depending again on the Hamiltonian), the 
time-structure of the wavefunction approximates a branching 

RE: White Rabbit vs. Tegmark

[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 surprise that we live in the world we do. For in those 
other worlds, conditions are such that stars and planets could never 
form, and so observers who are even remotely like us would never have 
evolved. The mere fact that we are having this discussion therefore 
necessitates that we live in a world where the physical laws and 
constants are very close to their present values, however unlikely such 
a world may at first seem. This is the anthropic principle at work.


(b) In the multiverse, those worlds in which it is a frequent occurence 
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 surprise that we live in the orderly 
world that we do. For in those other worlds, although observers very 
much like us may evolve, they will certainly not spend their time 
puzzling over the curious absence of white rabbit type phenomena. The 
mere fact that we are having this discussion therefore necessitates that 
we live in a world where physical laws are never violated, however 
unlikely such a world may at first seem. This is the *extreme* anthropic 
principle at work.


If there is something wrong with (b), why isn't there also something 
wrong with (a)?


--Stathis Papaioannou


Good point, this is a fundamental weakness of the AP. If you take it to 
extremes, we should not be surprised by *anything* because the entire 
history of our past light-cone to date, down to specific microscopic 
quantum events, is required in order to account for the fact that you and 
I are having this particular exchange. To give the AP force, you have to 
work on the most general possible level (hence it was a big mistake for 
Barrow  Tipler to restrict it to carbon-based life forms in their book, 
certainly not in line with Brandon Carter's original thought).


Paddy Leahy

Re: Nothing to Explain about 1st Person C!

[Bruno Marchal]

Le 25-mai-05, à 13:11, Stathis Papaioannou a écrit :



Lee Corbin writes:


 But we *still* don't know what it feels like to *be* the code
 implemented on a computer.
 We might be able to guess, perhaps from analogy with our own
 experience, perhaps by running the code in our head; but once
 we start doing either of these things, we are replacing the 3rd
 person perspective with the 1st person.

Yes.  Doesn't it seem that you want the impossible?  That you want
to be the code and yet remain someone else?

It seems like only by actually *being* that code---having its
emotional reactions, its same impressions of everything---can
you possibly know what it's like... to be the code. This point
was made by someone here before. Namely, that if *you* become
a bat in order to learn what it's like to be a bat, then you
aren't you anymore.


I agree with everything you have said. You have to be the code to know 
what it is like to be the code. And consciousness is the only thing in 
the universe of which this is true.


--Stathis


I do agree too. Mainly. But, to prevent future misunderstandings, I 
think it is better to say we are the owner of the code. If we forget 
this it will be hard to figure out later that consciousness can not 
been exclusively associated to the code but to some equivalence class 
of the code through the multiverse (or UD* the effective set of all 
computational histories). We would miss eventually the possibility of 
interference both with comp and with Everett's QM.


Bruno

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

Re: Induction vs Rubbish

[Patrick Leahy]

On Wed, 25 May 2005, Russell Standish wrote:


On Tue, May 24, 2005 at 10:10:19PM +0100, Patrick Leahy wrote:


Lewis also distinguishes between inductive failure and rubbish 
universes as two different objections to his model. I notice that in 
your articles both you and Russell Standish more or less run these 
together.




I'm interested in this. Could you elaborate please? I haven't had the 
advantage of reading Lewis.


If what you mean by by the first is why rubbish universes are not
selected for, it is because properties of the selected universe follow
a distribution with well defined probability, the universal prior like
measure. This is dealt in section 2 of my paper.

If you mean by failure of induction, why an observer (under TIME)
continues to experience non-rubbish, then that is the white rabbit
problem I deal with in section 3. It comes down to a robustness
property of an observer, which is hypothesised for evolutionary
reasons (it is not, evolutionarily speaking, a good idea to be
confused by hunters wearing camouflage!)

In that case, how am I conflating the two issues? If I'm barking up
the wrong tree, I'd like to know.


It's the second point where I think you conflate two problems.

My distinction is a little different from Lewis' anyway. From my pov, it's 
a matter of degree, but one which makes a qualitative difference:


* Failure of induction: the past fails to predict the future. This occurs 
in universes a la Hume where physical laws only appear to have been 
followed by some massive fluke. Also in universes which always had no, or 
very little, regularity. I claim that as soon as regularity breaks down to 
this extent, SAS cease to exist, so no matter how common these cases are, 
we never observe them. No problem. (Lewis' defence is different).


* White Rabbit: cognizable universes require a high degree of regularity 
for the survival of SAS (not to mention evolution), as above. Hence 
induction in any cognizable universe will work most of the time (which is 
all it does anyway), for a sufficient set of properties of the world. The 
key point is that this is not *every* property, and not all of the time. 
Hence there should be universes in which SAS can survive pretty well, but 
contain a wide variety of phenomena which cannot be unified into a simple 
theory.  An extreme case is the rubbish universe proposed against Lewis, 
in which the extra phenomena are completely undetectable. Lewis takes this 
as a serious objection and counters by arguing that it is not possible to 
say that such universes are more likely.  As scientists, I guess we 
would only take seriously detectable rubbish. NB: whatever the measure you 
use, unless extremely artificial, the rubbish almost certainly would have 
much higher entropy than talking White Rabbits. Think of reality has 
having snow, like a badly-tuned TV.


Of course on objective state-reduction models of QM, our universe does 
have snow in the form of random quantum jumps. But this is a very 
regular form of snow, which does unify into the basic physical laws. The 
argument is that for some plausible measures (not yours, obviously), even

macro-scale snow is much more likely than not.

Paddy Leahy

RE: Sociological approach

[aet.radal ssg]

It was "contemptuous" of the information on decoherence, which is what popped up, when I clicked on the link. In particular the Julian Barbouresque "timelessness" prattle, "there are no particles", "there are no quantum jumps", etc. which seems far outside the definition of "decoherence". When I see such bold statements without explanation, I laugh. It doesn't really make wanna look further. But that was just an observer moment in the timeless space of Platonia. It wasn't even the same me that's typing this reply, which isn't the same me that began it, which isn't the same me that'll type...- Original Message -From: "Brent Meeker" <[EMAIL PROTECTED]>To: "Everything-List" Subject: RE: Sociological approachDate: Tue, 24 May 2005 14:06:52 -

That's a rather contemptous evaluation of a website thatreports on the work of some very good physicist, e.g. Zeh, Joos, Kim, and Tegmark. Do you have any substantive comment? Did you read any of the papers?

Brent Meeker

-Original Message-From: aet.radal ssg [mailto:[EMAIL PROTECTED]Sent: Tuesday, May 24, 2005 7:49 PMTo: everything-list@eskimo.comSubject: RE: Sociological approach
"See http://decoherence.de "? It was good for a laugh, not much else.- Original Message - From: "Brent Meeker" <[EMAIL PROTECTED]>To: "Everything-List" Subject: RE: Sociological approach Date: Mon, 23 May 2005 22:02:48 -  -Original Message-   From: rmiller [mailto:[EMAIL PROTECTED]   Sent: Monday, May 23, 2005 5:40 PM   To: Patrick Leahy   Cc: aet.radal ssg; EverythingList; Giu1i0 Pri5c0   Subject: Re: Sociological approach  ...   More to the point, if you happen to know why the mere act of   measurement--even at a distance-- "induces" a probability collapse, I'd   love to hear it.   Measurements are just interactions that project onto "pointer spaces" we're  interested in. There's nothing physically different from any other  interaction.  See http://decoherence.de/   Brent Meeker -- 
___Sign-up for Ads Free at Mail.comhttp://www.mail.com/?sr=signup


-- 
___Sign-up for Ads Free at Mail.com
http://www.mail.com/?sr=signup

RE: Observables, Measurables, and Detectors

[Brent Meeker]

-Original Message-
From: Patrick Leahy [mailto:[EMAIL PROTECTED]
Sent: Wednesday, May 25, 2005 12:25 PM
To: Lee Corbin
Cc: EverythingList
Subject: Re: Observables, Measurables, and Detectors



 It looks as though you advocate a role for each of these:

   observables
   measurements
   detectors

 and for all I know

   observers

 It seemed to me that MWI allowed me to get away with a considerable
 simplification. Gone were observers and even observations. Even
 measurements, I discard. (After all, who can say that a measurement
 occurs in the middle of a star? And yet things do go on there, all
 the time.)

 Now *some* of that language perhaps returns when decoherence is
 discussed. I mean, I'll grant that *something* significant starts
 off a new branch, and so it's okay for it to have a name.  :-)

 But here is what I'd like to be able to say:

 A new branch starts, or decoherence obtains, or an irreversible
 transformation occurs, or a record is made.  They all seem the
 same to me. Why not?

 My main motivation is to get as far away from Copenhagen as possible,
 and so thereby get free of observers and observations, and anything
 else that seems to afford some pieces of matter a privileged status.
 Do you think that such simplified language leaves out anything important?


I don't think we disagree much about the physics. The trouble is, the
physics is even simpler than you suggest. Branching is not something
special in the theory, it is a macroscopic description that we apply to
what emerges from the theory.  If you simplify your language too much, all
that happens is you have to define all those useful approximate terms from
scratch.

Just for fun, here's how it would go:

The framework of QM in the MWI is that

(1) The state of the system (universe) can be represented by a
time-dependant, normalized vector, say |S, in a Hilbert space.

(2) Time evolution of |S is linear.

That's it! (1) implies that time evolution is also unitary, so the vector
stays normed. (1) + (2) imply the Schrodinger equation, including the fact
that the generator of time evolution (Hamiltonian) is a Hermitian
operator. (2) causes all the trouble.

A full (non-framework) description requires you to (a) specify the Hilbert
space (b) specify the Hamiltonian (c) specify the initial state. None of
which are known exactly for the universe. (And in fact for the universe as
a whole we had better adapt this description to relativity somehow, since
you can't just take time as a given.)

Now to introduce some more specific terms so we can relate the theory to
everyday reality.

Observable: In a simple system, the set of values of an observable are
simply the labels we attach to elements of a basis, i.e. a set of
orthogonal unit vectors (defining a coordinate system), in Hilbert
space. We can freely choose any basis we like, but some are more useful
than others because they relate to the structure and symmetries of the
Hamiltonian. Let's call a basis {|o} where o is our variable label. The
set might be finite, denumerable, or continuous, depending on the size of
the Hilbert space. For convenience, and to make the transition to
classical physics as seamless as possible, the labels are usually chosen
to be real numbers.

To put my previous answer to Serafino into this context, note that
observables (e.g. position) play a very different role in the theory from
time.

For each basis, we can construct a linear operator on Hilbert-space
vectors whose eigenvectors are the basis vectors and whose eigenvalues are
our observable labels. If our labels are real, the operator will be
Hermitian. With suitable choice of labels, the algebra of some of these
operators approximately maps onto the algebra of variables in classical
physics, which explains why classical physics works, and also how QM was
discovered. (In particular, since the Hamiltonian itself is hermitian it
has a set of real eigenvalues which we call Energy).

Wave Function: The inner product of a basis vector with the state
vector, written o|S, is geometrically the length of the projection of
the state onto that basis vector, and so the cartesian coordinate along
the axis defined by |o. In conventional QM it is the probability
amplitude for observing o. If the basis is continuously infinite, as in
position or momentum, o|S is a continuous function of the real variable
(observable) o. This is what we call the wave function in o-space. (e.g.
o = position, or momentum).

Subsystems: In a complex system, we have to be a bit more careful. What
physicists call observables certainly don't parameterize a complete basis
for the universe. Such a complete basis would be characterised by a
complete set of commuting observables. Commuting because their
characteristic operators commute. In effect, we factorize the Hilbert
space into subspaces (corresponding to quasi-independent subsystems).
Practical observables correspond to bases on some subspace.

Branching: In *some* bases of 

Re: Induction vs Rubbish

[Benjamin Udell]

Patrick Leahy wrote: 
66~~
* White Rabbit: cognizable universes require a high degree of regularity for 
the survival of SAS (not to mention evolution), as above. Hence induction in 
any cognizable universe will work most of the time (which is all it does 
anyway), for a sufficient set of properties of the world. The key point is that 
this is not *every* property, and not all of the time. Hence there should be 
universes in which SAS can survive pretty well, but contain a wide variety of 
phenomena which cannot be unified into a simple theory.  An extreme case is the 
rubbish universe proposed against Lewis, in which the extra phenomena are 
completely undetectable. Lewis takes this as a serious objection and counters 
by arguing that it is not possible to say that such universes are more 
likely.  As scientists, I guess we would only take seriously detectable 
rubbish. NB: whatever the measure you use, unless extremely artificial, the 
rubbish almost certainly would have much higher entropy than talking Whi!
 te Rabbits. Think of reality has having snow, like a badly-tuned TV.
~~99

The induction-friendly universe with so much detectable rubbish that a wide 
variety of phenomena cannot be unified into a simple theory sounds like a 
universe where induction works but surmise, or inference to the simplest 
explanation, faces grave difficulties and too often fails. In other words, in 
difficult cases, efforts toward surmise -- i.e., rambling speculations about 
half-formed ideas that probably won't pan out to anything -- really will lead 
too often too far astray to be practicable, and cogent everyday surmises would 
be few and far between -- not everyday or quotidian at all. A greatly increased 
difficulty in the formation of explanatory hypotheses would, it seems, hamper 
not only science but SASs in general. Would intelligence and commonsense 
perception tend, on balance, to be useful in such a world? It sounds like a 
world which would allow vegetable-like systems (i.e., essentially mindless in 
the usual sense) but be severely punitive toward SASs inclined to t!
 ry to be shrewd or clever and to try, for instance, to infer particular 
entities or events or universal laws (as opposed to prolonged tendencies) as 
explanatory reasons, or to try to play architect instead of subsisting on the 
continuation of tendencies. It also sounds like the evolution or natural 
architecting of even merely vegetable-like systems would likely be under 
pressure to play it a lot safer than it does in our world, so that the systems 
thus evolved would tend to be not only vegetable-like but also a lot more 
generic than those which we see. I guess I'm trying to argue (unconfidently) 
or suggest, for what it's worth, that induction-friendly but much-detectable 
rubbish universes with SASs are induction-friendly but surmise-unfriendly 
universes with SASs, and that their measure would be rather small.

Best regards,
Ben Udell

- Original Message - 
From: Patrick Leahy [EMAIL PROTECTED]
To: Russell Standish [EMAIL PROTECTED]
Cc: Alastair Malcolm [EMAIL PROTECTED]; EverythingList 
everything-list@eskimo.com
Sent: Wednesday, May 25, 2005 9:11 AM
Subject: Re: Induction vs Rubbish

On Wed, 25 May 2005, Russell Standish wrote:

 On Tue, May 24, 2005 at 10:10:19PM +0100, Patrick Leahy wrote:

 Lewis also distinguishes between inductive failure and rubbish universes as 
 two different objections to his model. I notice that in your articles both 
 you and Russell Standish more or less run these together.


 I'm interested in this. Could you elaborate please? I haven't had the 
 advantage of reading Lewis.

 If what you mean by by the first is why rubbish universes are not selected 
 for, it is because properties of the selected universe follow a distribution 
 with well defined probability, the universal prior like measure. This is 
 dealt in section 2 of my paper.

 If you mean by failure of induction, why an observer (under TIME) continues 
 to experience non-rubbish, then that is the white rabbit problem I deal with 
 in section 3. It comes down to a robustness property of an observer, which 
 is hypothesised for evolutionary reasons (it is not, evolutionarily speaking, 
 a good idea to be confused by hunters wearing camouflage!)

 In that case, how am I conflating the two issues? If I'm barking up the wrong 
 tree, I'd like to know.

It's the second point where I think you conflate two problems.

My distinction is a little different from Lewis' anyway. From my pov, it's a 
matter of degree, but one which makes a qualitative difference:

* Failure of induction: the past fails to predict the future. This occurs in 
universes a la Hume where physical laws only appear to have been followed by 
some massive fluke. Also in universes which always had no, or very little, 
regularity. I claim that as soon as regularity breaks down to this extent, SAS 
cease to exist, so no matter how common these cases are, we 

Re: White Rabbit vs. Tegmark

[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 claims that you can't actually put a measure (he probably said: you
 can't define probabilities) on a countably infinite set, precisely because
 of Cantor's pairing arguments. Which seems plausible to me.

It seems to depend on whether one can find an intrinsic ordering (or
something similar), such that relative frequency comes into play (so prime
numbers *would* be less likely to be hit). As implied by my paper this would
suggest a solution to the WR problem, but even if no ordering is possible or
is irrelevant - the simple Cantorian situation - then there would be no WR
problem anyway. (I have read hopefully the relevant passages in 'On the
Plurality of Worlds' - I would think you are mainly referring to section
2.5;  he doesn't actually mention either 'measure' or 'probability' here as
far as I can see - more like 'outnumber', 'abundance' etc.)

 Lewis also distinguishes between inductive failure and rubbish universes
 as two different objections to his model. I notice that in your articles
 both you and Russell Standish more or less run these together.

Lewis' approach to the inductive failure objection is slightly different,
with the result that he can deploy a separate argument against it. Where he
says

Why should the reason everyone has to distrust induction seem more
formidable when the risk of error is understood my way: as the existence of
other worlds wherein our counterparts are deceived? It should not. [p117]

... he is basically saying that from a deductive-logic point of view we have
some degree of mistrust of induction anyway, and this will not be affected
whether we consider the possible worlds (where induction fails) to be real
or imaginary.

However, it is the (for me) straightforward 'induction failure' objection -
that the world should in all likelihood become unpredictable from the next
moment on - that I address in my paper, (which in many ways more
closely links to Lewis's 'rubbish universe' objection); my mentioning of
'rubbish' is in the different context of *invisible* universes, which is in
the appendix argument concerning predomination of simpler universes.

Alastair

Re: Induction vs Rubbish

[Patrick Leahy]

On Wed, 25 May 2005, Benjamin Udell wrote:



The induction-friendly universe with so much detectable rubbish that a 
wide variety of phenomena cannot be unified into a simple theory sounds 
like a universe where induction works but surmise, or inference to the 
simplest explanation, faces grave difficulties and too often fails. In 
other words, in difficult cases, efforts toward surmise -- i.e., 
rambling speculations about half-formed ideas that probably won't pan 
out to anything -- really will lead too often too far astray to be 
practicable, and cogent everyday surmises would be few and far between 
-- not everyday or quotidian at all. A greatly increased difficulty in 
the formation of explanatory hypotheses would, it seems, hamper not only 
science but SASs in general. Would intelligence and commonsense 
perception tend, on balance, to be useful in such a world? It sounds 
like a world which would allow vegetable-like systems (i.e., essentially 
mindless in the usual sense) but be severely punitive toward SASs 
inclined to try to be shrewd or clever and to try, for instance, to 
infer particular entities or events or universal laws (as opposed to 
prolonged tendencies) as explanatory reasons, or to try to play 
architect instead of subsisting on the continuation of tendencies. It 
also sounds like the evolution or natural architecting of even merely 
vegetable-like systems would likely be under pressure to play it a lot 
safer than it does in our world, so that the systems thus evolved would 
tend to be not only vegetable-like but also a lot more generic than 
those which we see. I guess I'm trying to argue (unconfidently) or 
suggest, for what it's worth, that induction-friendly but 
much-detectable rubbish universes with SASs are induction-friendly but 
surmise-unfriendly universes with SASs, and that their measure would be 
rather small.


Best regards,
Ben Udell


It's a question of degree, again. There is surely a level of noise which 
doesn't cause the problems you mention (although I would say that surmise, 
common sense etc are basically inductive reasoning from past experience, 
including past experience genetically encoded by natural selection which 
is one big inductive experiment). For most of history, the world has 
seemed a pretty random place to people (probably still does to most 
people), but they managed to survive without understanding how QM unifies 
the structure of matter, Natural selection explains so much about living 
things, etc. If the rubbish was there, we'd get used to it. Only 
scientists would be frustrated that they couldn't make any kind of sense 
of it. But they would be able to isolate the features of their world which 
did show regularity, so it wouldn't prevent science, either.


Paddy

Re: Plaga

[Saibal Mitra]

Plaga's paper has been published:

''Proposal for an experimental test of the 
many-worlds interpretation of quantum mechanics''

Found.Phys. 27 (1997) 559

arXiv: quant-ph/9510007




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

  - Oorspronkelijk bericht - 
  Van: 
  aet.radal 
  ssg 
  Aan: everything-list@eskimo.com 
  Verzonden: Wednesday, May 25, 2005 05:59 
  PM
  Onderwerp: Re: Plaga
  
  From the initial page from the included link to the archive: "I'm no 
  physicist so I don't know for sure that these implications wouldfollow, 
  but I am very doubtful that interworld communication is consistentwith the 
  basics of quantum mechanics. The fact that this paper has notbeen 
  published in peer reviewed journals in 7 years indicates that itprobably 
  doesn't work."
  Back when I wasn't long in the field of video production I was well aware 
  of the insistance and belief of TV engineers that a single tube industrial 
  color video camera was not broadcast quality. Working in cable, where they 
  were used for cablecast, I had plenty of opportunity to look at picture 
  quality, etc. and came to the conclusion that it shouldn't be a problem. 2 
  years later I got the chance to prove it when a local news station sent a crew 
  out to cover something that I was shooting. In the end I gave them 
  theeditied sequence I had shot (now downtwo generations), and they 
  took it and edited it into their story, which would have taken it down a 
  third. Then they broadcasted it over the air. I taped it off-air and the 
  results were conclusive - I wasright, all the nay-sayer engineers were 
  wrong.A $40,000 Ikegami vs a $1,500 Panasonic and it was a tie 
  except for one slight red bleed from a costume due to the Saticon tube bias 
  toward red in the camera I used, which could have been color corrected with a 
  time base corrector, but whoever dubbed the tape left the red level a little 
  too hot. 
  My point being that that was the first in a long line of "you can'ts" that 
  I've faced which I eventually proved, "you can". Thus I have a dim view of 
  such positions when they aren't backed up with experiments that prove so 
  *conclusively*. As long as the possibility exists, I keep an open mind. 
  Besides, if unbriddled skepticism was right all the time, we wouldn't be using 
  computers, flying, or even have phones of any kind, just to name a few 
  things.- Original Message - From: [EMAIL PROTECTED] 
  To: everything-list@eskimo.com Subject: Re: Plaga Date: Tue, 24 
  May 2005 17:51:13 -0700 (PDT)   We discussed Plaga's paper 
  back in June, 2002. I reported some skeptical  analysis of the paper 
  by John Baez of sci.physics fame, at  
  http://www.escribe.com/science/theory/m3686.html . I also gave some  
  reasons of my own why arbitrary inter-universe quantum communication  
  should be impossible.   Hal Finney -- 
  ___Sign-up for 
  Ads Free at Mail.comhttp://www.mail.com/?sr=signup

Re: Plaga

[Jesse Mazer]

aet.radal ssg wrote:

From the initial page from the included link to the archive: I'm no 
physicist so I don't know for sure that these implications would

follow, but I am very doubtful that interworld communication is consistent
with the basics of quantum mechanics.  The fact that this paper has not
been published in peer reviewed journals in 7 years indicates that it
probably doesn't work.

Back when I wasn't long in the field of video production I was well aware 
of the insistance and belief of TV engineers that a single tube industrial 
color video camera was not broadcast quality. Working in cable, where they 
were used for cablecast, I had plenty of opportunity to look at picture 
quality, etc. and came to the conclusion that it shouldn't be a problem. 2 
years later I got the chance to prove it when a local news station sent a 
crew out to cover something that I was shooting. In the end I gave them 
the editied sequence I had shot (now down two generations), and they took 
it and edited it into their story, which would have taken it down a third. 
Then they broadcasted it over the air. I taped it off-air and the results 
were conclusive - I was right, all the nay-sayer engineers were wrong. A 
$40,000 Ikegami  vs a $1,500 Panasonic and it was a tie except for one 
slight red bleed from a costume due to the Saticon tube bias toward red in 
the camera I used, which could have been color corrected with a time base 
corrector, but whoever dubbed the tape left the red level a little too hot.


My point being that that was the first in a long line of you can'ts that 
I've faced which I eventually proved, you can. Thus I have a dim view of 
such positions when they aren't backed up with experiments that prove so 
*conclusively*. As long as the possibility exists, I keep an open mind. 
Besides, if unbriddled skepticism was right all the time, we wouldn't be 
using computers, flying, or even have phones of any kind, just to name a 
few things.


There is a fundamental difference between claims that we can never do 
something because the engineering problems are too great, and claims that we 
can never do something because the laws of physics themselves say it's 
impossible. For example, I've heard people say things like I'm sure we'll 
eventually break the light-speed barrier, after all, once people thought it 
was impossible that we'd ever break the sound barrier but they've been 
proved wrong. But the two are not really comparable, because no one ever 
thought the laws of physics said breaking the sound barrier was impossible, 
they just thought the technical challenges to doing so would be too 
difficult, whereas the light-speed barrier is built into the basic structure 
of relativity (although there are possible loopholes in general relativity 
like wormholes, where you get to distant destinations quickly without ever 
*locally* exceeding the speed of light).


Similarly, when Hal Finney suggests he thinks interworld communication is 
impossible, I think he's suggesting that it would violate basic principles 
of QM, not that it's too big of a technical challenge. I also saw this 
suggested in the book Schrodinger's Rabbits by Colin Bruce, a pop science 
book about the MWI (p. 137):


If only we could do a clear and unambiguous communication-between-worlds 
experiment. Then there would be no room for argument about the reality of 
many-worlds. Unfortunately, the laws of physics do not seem to allow such a 
thing.


This is frustrating because two potentially useful methods of harnessing 
the power of many-worlds, which we will look at in detail shortly, can be 
described in terms of sharing resources between worlds, or even sharing 
information between worlds. For example, a loose way of describing the 
operation of a quantum computer is as follows: As worlds start to diverge, 
hundreds of billions of different copies of the computer come into 
existence. Each of these computer copies can work on a different 
calculation. The shared results of their labors, however, can be made 
available to all the diverging worlds created when the bubble of Hilbert 
space describing the computer is systematically collapsed by measurement at 
the end of the calculation.


This makes it sound as if Hilbert space might possibly be used as a kind of 
mailbox for communicating between worlds. Unfortunately, the mathematics 
that describes Hilbert space rules this out because it implies that 
everything that goes on in Hilbert space is reversible. As soon as you try 
to take information out of Hilbert space, that reversibility is destroyed. 
Such acts of measurement, by definition, cause decoherence. You can preserve 
multiworld access to a bubble of Hilbert space only by allowing it to evolve 
undisturbed. It reminds me of C.S. Lewis's Wood Between the Worlds 
described in the Magician's Nephew. Any Hilbert space accessible from more 
than one world line must be a timeless place, in which we can leave no 
permanent mark.

Re: Plaga

[Bruno Marchal]

Le 25-mai-05, à 17:59, aet.radal ssg a écrit :

From the initial page from the included link to the archive: I'm no 
physicist so I don't know for sure that these implications would
follow, but I am very doubtful that interworld communication is 
consistent

with the basics of quantum mechanics.  The fact that this paper has not
been published in peer reviewed journals in 7 years indicates that it
probably doesn't work.


Ooh... you should not make inferences like that. I could give you 
10,000 reasons for not publishing. But I have not the time because I 
have a deadline today!


I red Plaga's paper. It is extremely interesting. It belongs to the 
family of Weinberg's result. Some hoped that a slight delinearisation 
of QM would explain the collapse. Reasoning a-la Weinberg Plaga shows 
that it is the contrary which happens. Not only we keep the MW but they 
became more real in some sense.  It shows the MWI is stable for 
slight variation of the SWE. this confirms MWI in a deeper way. It 
shows quantum non linearity  contradicts thermodynamics! This is a 
powerful argument in favor of both pure linear QM and MWI.


(Good for me, it shows nature confirms the lobian machine's inability 
to observe kestrels and starlings when they look enough closely to 
themselves)


Bruno

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

RE: White Rabbit vs. Tegmark

[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) 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 surprise that we live 
 in the world we do. For in those other worlds, conditions are 
 such that stars and planets could never form, and so 
 observers who are even remotely like us would never have 
 evolved. The mere fact that we are having this discussion 
 therefore necessitates that we live in a world where the 
 physical laws and constants are very close to their present 
 values, however unlikely such a world may at first seem. This 
 is the anthropic principle at work.
 
 (b) In the multiverse, those worlds in which it is a frequent 
 occurence 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 
 surprise that we live in the orderly world that we do. For in 
 those other worlds, although observers very much like us may 
 evolve, they will certainly not spend their time puzzling 
 over the curious absence of white rabbit type phenomena. The 
 mere fact that we are having this discussion therefore 
 necessitates that we live in a world where physical laws are 
 never violated, however unlikely such a world may at first 
 seem. This is the
 *extreme* anthropic principle at work.
 
 If there is something wrong with (b), why isn't there also 
 something wrong with (a)?

This is the problem of determining the appropriate class of observer we
should count ourselves as being a random selection on. There might indeed be
something wrong with (a); replace The mere fact that we are having *this*
discussion with, The mere fact that we are having *a* discussion to
obtain a dramatically different observer class. Your formulation of (a)
(*this* discussion) essentially restricts us to being a random selection on
the class of observers with access to internet and email, discoursing on the
everything list. Replacing this with a broadens the class to include
any intelligent entity capable of (and having) a discussion. 

The problem of determining the appropriate class seems a rather intractable
one. Choosing too broad a class can lead to unpleasant consequences such as
the doomsday argument; too narrow a class leads to (b). Mondays, wednesdays
and fridays, I believe that my appropriate reference class can be only one;
Jonathan Colvin in this particular branch of the MW, since I could not
have been anyone else. Weekends, tuesdays and thursdays I believe I'm a
random observer on the class of observers.

Jonathan Colvin

RE: What do you lose if you simply accept...

[Jonathan Colvin]

**
Interleaving;
***

Bruno: But we can photosynthesize. And we can
understand why we 
cannot travel at the speed of light. All this by
using purely 
3-person description of those phenomena in some
theory.
With consciousness, the range of the debate goes
from 
non-existence to only-existing. The problem is that
it seems 
that an entirely 3-person explanation of the
brain-muscles 
relations evacuates any purpose for consciousness
and the 
1-person. That's not the case with photosynthesis.



JC: You can photosynthesize? I certainly can not (not being
a tree). If I had
photosynthetic pigments in my skin, I suppose I could; and
if I had rubbery
wings and sharp teeth I'd be a bat (if my aunt had wheels,
she'd be a
wagon). I still can not see (intellectually) the problem
of consciousness.



I said I can photosynthetize, like I would said I can fly by taking
a plane. I can photosynthetize by building some voltaic cells. This is not
the case with the brain-consciousness relation. A thorough understanding of
how the brain functions *seems* to put away any purpose of consciousness. A
thorough understanding of photosynthesis does not lead to an equivalent
problem.


*
By consciousness, I think you mean qualia. Consciousness can easily be
conflated with self-awareness, which has an evolutionary purpose (it
enables us to step outside our own minds (treat them as virtual machines),
and thus anticipate our own and others' actions).  
*


I still can not see (intellectually) the problem of
consciousness.



It is the problem of relating first person subjective private
experience with third person sharable theories and experiments. There is a
vast literature. A good intro is
Tye, M. (1995). Ten problems of consciousness. The MIT Press,
Cambridge, Massachusetts.

*
If you deny (as I do) that there is such a thing as first person
subjective experience (qualia) the problem goes away.
*

Consciousness /qualia, 1st person phenomena, etc, IMHO,
being very poorly
defined, 



Universes, matter, existence,... are also not well defined. Perhaps
you are not interested in such problems. The success of natural science is
due in great part to the simplifying assumption of
psychophysico-parallelism. I have proved such an assumption is just
incompatible with the computationalist assumption in cognitive science.




I have also reduce the problem of the existence of the 1-person to
the problem of the existence of third person sharable truth. And partially
solve it.
My problem: few physicist knows what axiomatic methodology is. It is
the art of reasoning without even trying to define the concept on which we
reason. We need just to agree on properties bearing on those things,
captured by formula and inference rules. Mathematicians proceed in this way
since more than one century now.



and likely non-existing entities, 



What about the person's right? What about pleasure and pain, ... It
seems to me you just excluded those things from your definition of science,
and I'm afraid you make the category error I have describe recently.


Rights, pleasure, pain...I don't deny we can talk about these (like shadows)
*as if* they actually exist, but they do not fall into the same category of
things as electrons and universes, or indeed any other part of Platonia. I
do indeed exclude them from science, but I think the category error is not
mine. 






are a precarious pillar to base
any cosmology or metaphysics on. 



With comp, we just have no choice in the matter. If you are
interested at some point we can follow the proof step by step. I'm always
interested where, precisely, some people have some difficulties.


To borrow a page from Penrose, I see qualia in much the same
light as a
shadow. 



As an (arithmetical) platonist this is how I conceive anything
physical. Qualia are more colourful it seems to me. Wave lenght looks more
like shadows imo.

***
I am also an arithmetical Platonist, but where we differ is our belief in
the relevance of 1st person phenomena. I just don't see that they are
relevant to anything other than human 

RE: White Rabbit vs. Tegmark

[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 surprise that we live in the orderly 
  world that we do. For in those other worlds, although observers very 
  much like us may evolve, they will certainly not spend their time 
  puzzling over the curious absence of white rabbit type phenomena. The 
  mere fact that we are having this discussion therefore necessitates that 
  we live in a world where physical laws are never violated, however 
  unlikely such a world may at first seem. This is the *extreme* anthropic 
  principle at work.

Might it not also seem more probable (upon some of the hypotheses
being entertained here) that observers *just* like us evolved, and
then just today white rabbits began to appear out of nowhere?

 Good point, this is a fundamental weakness of the AP. If you take it to 
 extremes, we should not be surprised by *anything* because the entire 
 history of our past light-cone to date, down to specific microscopic 
 quantum events, is required in order to account for the fact that you and 
 I are having this particular exchange.

But is the entire history... down to quantum events  really
necessary to account for this exchange?  I say this because the
set of all the observer moments *this* seems to require covers
so many possibilities, including schizophrenia, etc. But...
this being so tricky, how may I have misunderstood?

Lee

 To give the AP force, you have to 
 work on the most general possible level (hence it was a big mistake for 
 Barrow  Tipler to restrict it to carbon-based life forms in their book, 
 certainly not in line with Brandon Carter's original thought).
 
 Paddy Leahy

RE: Observables, Measurables, and Detectors

[Lee Corbin]

Paddy writes

  A new branch starts, or decoherence obtains, or an irreversible
  transformation occurs, or a record is made.  They all seem the
  same to me. Why not?
 
  My main motivation is to get as far away from Copenhagen as possible,
  and so thereby get free of observers and observations, and anything
  else that seems to afford some pieces of matter a privileged status.
  Do you think that such simplified language leaves out anything important?
 
 I don't think we disagree much about the physics. The trouble is, the 
 physics is even simpler than you suggest.

Oh good!

 Branching is not something special in the theory, it is a macroscopic
 description that we apply to what emerges from the theory.

And so I take it that this applies to the rest of it that bothers
me: observables, observations, measurements, detectors---all those
things that you have kindly taken the time to develop from scratch
below.

 If you simplify your language too much, all that happens is you have
 to define all those useful approximate terms from scratch.

Very good. That *does* answer my question. At least I think it does.

We *start* with the ontology of (1) and (2), as you do below.
And actually---for a great number of philosophic purposes---
we are done. The rest is comfy language good for a little day-
to-day work in the lab. You probably realize what ammunition
this gives some of us in other debates  :-)

Building up from down deep (the way you do next) is even better
than reducing our usual notions (even when the latter is really
understood to mean the former).

Lee

 Just for fun, here's how it would go:
 
 The framework of QM in the MWI is that
 
 (1) The state of the system (universe) can be represented by a 
 time-dependant, normalized vector, say |S, in a Hilbert space.
 
 (2) Time evolution of |S is linear.
 
 That's it! (1) implies that time evolution is also unitary, so the vector 
 stays normed. (1) + (2) imply the Schrodinger equation, including the fact 
 that the generator of time evolution (Hamiltonian) is a Hermitian 
 operator. (2) causes all the trouble.
 
 A full (non-framework) description requires you to (a) specify the Hilbert 
 space (b) specify the Hamiltonian (c) specify the initial state. None of 
 which are known exactly for the universe. (And in fact for the universe as 
 a whole we had better adapt this description to relativity somehow, since 
 you can't just take time as a given.)
 
 Now to introduce some more specific terms so we can relate the theory to 
 everyday reality.
 
 Observable: In a simple system, the set of values of an observable are 
 simply the labels we attach to elements of a basis, i.e. a set of 
 orthogonal unit vectors (defining a coordinate system), in Hilbert 
 space. We can freely choose any basis we like, but some are more useful 
 than others because they relate to the structure and symmetries of the 
 Hamiltonian. Let's call a basis {|o} where o is our variable label. The 
 set might be finite, denumerable, or continuous, depending on the size of 
 the Hilbert space. For convenience, and to make the transition to 
 classical physics as seamless as possible, the labels are usually chosen 
 to be real numbers.
 
 To put my previous answer to Serafino into this context, note that 
 observables (e.g. position) play a very different role in the theory from 
 time.
 
 For each basis, we can construct a linear operator on Hilbert-space 
 vectors whose eigenvectors are the basis vectors and whose eigenvalues are 
 our observable labels. If our labels are real, the operator will be 
 Hermitian. With suitable choice of labels, the algebra of some of these 
 operators approximately maps onto the algebra of variables in classical 
 physics, which explains why classical physics works, and also how QM was 
 discovered. (In particular, since the Hamiltonian itself is hermitian it 
 has a set of real eigenvalues which we call Energy).
 
 Wave Function: The inner product of a basis vector with the state 
 vector, written o|S, is geometrically the length of the projection of 
 the state onto that basis vector, and so the cartesian coordinate along 
 the axis defined by |o. In conventional QM it is the probability 
 amplitude for observing o. If the basis is continuously infinite, as in 
 position or momentum, o|S is a continuous function of the real variable 
 (observable) o. This is what we call the wave function in o-space. (e.g. 
 o = position, or momentum).
 
 Subsystems: In a complex system, we have to be a bit more careful. What 
 physicists call observables certainly don't parameterize a complete basis 
 for the universe. Such a complete basis would be characterised by a 
 complete set of commuting observables. Commuting because their 
 characteristic operators commute. In effect, we factorize the Hilbert 
 space into subspaces (corresponding to quasi-independent subsystems). 
 Practical observables correspond to bases on some subspace.
 
 Branching: In *some* bases of 

RE: Sociological approach

[Lee Corbin]

Richard writes

 How, essentially, does this differ from the casino game of
 roulette?

SNIP

 And there are people who are good at it.  Everyone calls them lucky which 
 really doesn't explain much.  Some of us routinely choose the wrong queue, 
 others get the correct one (queuing theory and probability offer good 
 explanations for this sort of thing, but other factors may simply involve 
 an ability to sample alternate worlds.

I don't believe that there are lucky people, except as a perfectly
ordinary and expected random fluctuation. If there were, don't you
think that it would pay the casinos to find these people and keep
them from playing?  And why haven't the psychics been all over
this? Besides, there are plenty of scientists who'd lust *jove*
to prove this.

Lee

RE: Sociological approach, luck, and the WTC surge cloud

[rmiller]

At 08:51 PM 5/25/2005, Lee Corbin wrote:
At 09:33 PM 5/25/2005, you wrote:

Richard writes

 How, essentially, does this differ from the casino game of
 roulette?

SNIP

LC: I don't believe that there are lucky people, except as a perfectly
ordinary and expected random fluctuation.


RM: Obviously it will be difficult to quantify the term lucky, but some 
people do win regularly at roulette.  Some also win the lottery, a very 
*lucky* few more than once.  Then there was the kite-maker who was in 
Hiroshima during the bombing who then drove home to tell his wife about 
it---in Nagasaki (unlucky). One can always cite perfectly ordinary and 
expected random fluctuations, for just about any event.  Reliance on 
perfectly ordinary and expected random fluctuations is fine if you 
establish your criteria for significance---the statistician Fisher set it 
at 1 in 20 (p0.05---and if we're doing multiple correlations, then we use 
the Bonferroni adjustment http://home.clara.net/sisa/bonhlp.htm.  So, I 
guess this is a good place to ask: what is your criteria for significance 
for the type of experiment I suggest?



LC: If there were, don't you
think that it would pay the casinos to find these people and keep
them from playing?


RM:  Objection. Calls for speculation. I don't operate a casino, so I 
really don't know what business decisions they may make.  In fact, I'm fine 
NOT knowing what business decisions they make.



LC: And why haven't the psychics been all over
this?


RM:  More speculation.  Please define psychic.  If you're including the 
engineers like Robert Jahn (formerly) with the PEAR lab, I suspect he--and 
others there have looked into it.  If you're including Madame Leanne down 
on Chartres Street in New Orleans, then, no--I don't think she cares one 
way or the other.  She's probably more interested in black cats, incense, 
money and that sort of thing.  If you're including Rupert Sheldrake in 
this category, then I'd probably have to ask you *why* you've included 
him.  *Psychic* covers a lot of territory.


As for the term all over (sorry, I got this from my editors) you'll 
probably have to explain yourself on this one too.  The inference seems to 
suggest that all the psychics--including Madame Leanne, Jahn, Sheldrake, 
et al--are banding together, marching down some street, banner held high 
with*something* written on it.  Maybe: Luck is real and demonstrable 
at the p0.0005 level.  I don't recall seeing anything of the sort, so, 
by those critera, I guess I shouldn't try that experiment, eh?  Gee.



LC: Besides, there are plenty of scientists who'd lust *jove*
to prove this.
RM (embarking on an extended rant that only *appears* to be off the 
subject, but actually addresses the criteria many scientists use in 
choosing what to investigate):


Yes.  But *only* if some agency blurts out funding for it.  Why did Texas 
AM scientists spend months studying how to turn lead into gold?  Because 
someone *paid* them to do it.  Actually, there's a much better smoking 
gun:  The investigation of the WTC Surge Clouds.


Remember the 9-11 dust clouds that roared up the street at 35 mph?   They 
choked everyone in sight with a mix of pH10.0 (Drano strength) Portland 
cement, mercury, tiny bits of Am241 (from hundreds of smoke detectors at 1 
uCi each)-


Now, as a scientist, I'm sure you are aware that NIOSH and OSHA set 
standards for exposure that are given in milligrams per cubic meter.  There 
is even such a standard for particulate---including respirable particulate 
(such as was in the aforementioned dust cloud.)  Now, for the past four 
years there have been hundreds of academic exposure experts slogging away 
at this exposure issue, but I cannot recall reading where anyone (EPA, 
NIOSH, anyone at Rutgers) ever published what the density of that dust 
cloud was in milligrams per cubic meter.  Maybe they did, and IF they did, 
three cheers for them!   But I don't think it's ever been done by any of 
these smart guys.


If there are plenty of scientists working on the WTC dust cloud 
exposures, and they still haven't told us what the density of that dust 
cloud was, at, say, Church street in NYC on that bad day, then how can we 
expect these same guys to even consider exploring something as mundane as 
what I suggested in an earlier post?


Sorry to all for the long-winded reply.  Anyone here care to try their hand 
at guessing what the average density of the WTC surge clouds were?   Be the 
first on the Net with an answer. ---Unless, of course, you can find it in 
the documents--which, IF you can---you'd be. . .well, *lucky.*  And I, of 
course, will humbly eat parbroiled crow and apologize to those hard-working 
environmental scientists over at the EPA and NIOSH and OSHA---and even 
those guys at Rutgers.


Bottom line:  Many scientists fail to study things not because it's worth 
studying, but because no one drops a wad of $1000 bills on their desk 
beforehand---and agrees to build a new 

RE: Plaga

[Lee Corbin]

I could not find who suggested Plaga's paper recently, but
thanks to whoever it was. Whether Plaga is right or wrong,
his introductory remarks and general presentation are
simply superb.

There is even the very noteworthy (or humorous, I can't decide)
sentence which reads Independent of what one thinks about the
MWI a priori, this is also a very systematic way to make
experimental progress in the  question of the interpretation
of QM, because in the MWI the predictions for any conceivable
experiment are free from philosophical subtleties...(!)

Lee

P.S. Thanks also to Saibal:

 Plaga's paper has been published:
 
 Proposal for an experimental test of the
 many-worlds interpretation of quantum mechanics
 
http://xxx.lanl.gov/PS_cache/quant-ph/pdf/9510/9510007.pdf


Found.Phys. 27 (1997) 559
 
arXiv: quant-ph/9510007

 -Original Message-
 From: Hal Finney [mailto:[EMAIL PROTECTED]
 Sent: Tuesday, May 24, 2005 5:51 PM
 To: everything-list@eskimo.com
 Subject: Re: Plaga
 
 We discussed Plaga's paper back in June, 2002.  I reported some skeptical
 analysis of the paper by John Baez of sci.physics fame, at
 http://www.escribe.com/science/theory/m3686.html .  I also gave some
 reasons of my own why arbitrary inter-universe quantum communication
 should be impossible.
 
 Hal Finney

Re: Induction vs Rubbish

[Russell Standish]

On Wed, May 25, 2005 at 02:11:56PM +0100, Patrick Leahy wrote:
 
 If you mean by failure of induction, why an observer (under TIME)
 continues to experience non-rubbish, then that is the white rabbit
 problem I deal with in section 3. It comes down to a robustness
 property of an observer, which is hypothesised for evolutionary
 reasons (it is not, evolutionarily speaking, a good idea to be
 confused by hunters wearing camouflage!)
 
 In that case, how am I conflating the two issues? If I'm barking up
 the wrong tree, I'd like to know.
 
 It's the second point where I think you conflate two problems.
 
 My distinction is a little different from Lewis' anyway. From my pov, it's 
 a matter of degree, but one which makes a qualitative difference:
 
 * Failure of induction: the past fails to predict the future. This occurs 
 in universes a la Hume where physical laws only appear to have been 
 followed by some massive fluke. Also in universes which always had no, or 
 very little, regularity. I claim that as soon as regularity breaks down to 
 this extent, SAS cease to exist, so no matter how common these cases are, 
 we never observe them. No problem. (Lewis' defence is different).

This is easy to assert, but less easy to prove. It also does not
explain away the non appearance of unlawful phenomena that do not
affect the observer's existence. There are still far more worlds of
this kind than lawful ones. The point I make in my paper is that the
vaste majority of these unlawful worlds will be indistinguishable from
lawful ones, or lawful ones + magic. The universal prior then comes
into play - the total measure of  lawless worlds indistinguishable
from lawful ones will be vastly greater than this indistinguishable
from lawful worlds + magic.



 
 * White Rabbit: cognizable universes require a high degree of regularity 
 for the survival of SAS (not to mention evolution), as above. Hence 
 induction in any cognizable universe will work most of the time (which is 
 all it does anyway), for a sufficient set of properties of the world. The 
 key point is that this is not *every* property, and not all of the time. 
 Hence there should be universes in which SAS can survive pretty well, but 
 contain a wide variety of phenomena which cannot be unified into a simple 
 theory.  An extreme case is the rubbish universe proposed against Lewis, 
 in which the extra phenomena are completely undetectable. Lewis takes this 
 as a serious objection and counters by arguing that it is not possible to 
 say that such universes are more likely.  As scientists, I guess we 
 would only take seriously detectable rubbish. NB: whatever the measure you 
 use, unless extremely artificial, the rubbish almost certainly would have 
 much higher entropy than talking White Rabbits. Think of reality has 
 having snow, like a badly-tuned TV.

Indeed. Undetectable rubbish is not a problem. Only magic. And magic
has provably less measure :)

 
 Of course on objective state-reduction models of QM, our universe does 
 have snow in the form of random quantum jumps. But this is a very 
 regular form of snow, which does unify into the basic physical laws. The 
 argument is that for some plausible measures (not yours, obviously), even
 macro-scale snow is much more likely than not.
 
 Paddy Leahy

Yes - some on this list have speculated that quantum randomness is a
manifestation of this - can't remember what we concluded now though...

Cheers

-- 
*PS: A number of people ask me about the attachment to my email, which
is of type application/pgp-signature. Don't worry, it is not a
virus. It is an electronic signature, that may be used to verify this
email came from me if you have PGP or GPG installed. Otherwise, you
may safely ignore this attachment.


A/Prof Russell Standish  Phone 8308 3119 (mobile)
Mathematics0425 253119 ()
UNSW SYDNEY 2052 [EMAIL PROTECTED] 
Australiahttp://parallel.hpc.unsw.edu.au/rks
International prefix  +612, Interstate prefix 02



pgpppZTonR6yY.pgp
Description: PGP signature