Dear Chris,
I hope to be able to convince you that the ideas that you express below do not yield a coherent narrative. But you must make up your own mind. There are so many assumptions being made that must be reconsidered... What is your background?
----- Original Message -----
From: "chris peck" <chris_peck303.domain.name.hidden>
To: <stephenk1.domain.name.hidden>
Cc: <everything-list.domain.name.hidden>
Sent: Monday, July 11, 2005 9:48 AM
Subject: Re: The Time Deniers and the idea of time as a "dimension"
> Hi Stephen;
>
> I suppose we can think of time as a dimension. However, there are provisos.
[SPK]
Did you happen to note that my post argued that the idea that "time is a dimension" can only be taken as true in an a posteriori sense? It is when we try to force the entirety of our notions relating to time to fit into the mold of an a priori given ordering of events that things run awry.
How familiar are you with the details of quantum mechanics? Did you happen to know that the notion of an observable in QM has a complex value and that a real value only obtains after the multiplication of an observable with its complex conjugate? This operation of conjugation must involve the selection of some basis.. This makes the problem of a pre-existing Real value time to be, at least, doubly difficult.
Complex numbers have no natural ordering, as opposed to the Reals, which do, because in general, complex numbers do not commute with each other. Only the very special subset of observables can be said to commute and thus can be mapped to some notion of a "dimension" that one can have translational transforms as functions.
In order to have coherent ideas like "time travel", a moving "now" like some flash-light beam that can be moved forwards and backwards, require such contorted mathematics that one can hardly argue that that is how Nature works.
> [CP]
> Time is not like x, y, or z in so far as we have no ability to freely
> navigate the axis in any direction we choose. We are embedded in time and it
> moves onwards in a single direction without anyone's consent. Furthermore,
> where it possible to move around in time all sorts of paradoxes would appear
> to ensue that just don't when I traverse the spatial dimensions. I'd appeal
> to an asymmetry between time and space, it is a dimension of sorts, but not
> one that can conceptually swapped with a spatial dimension easily. I don't
> think the a priori requirements for space will be necessarily the same as
> those for time.
[SPK]
All we seem to be able to control about time is its rate; we do this by accelerating things or, equivalently, changing their position with respect to gravitational gradients. On the other hand, the notion of "free will" - which some argue is purely an illusion- implies the ability to simultaneously consider some set of possible optional "nows" and chose one as the "next". This is the locus of conflict between the determinism of the classical world and QM where it is said that God(s) play with Dice.
How familiar are you with the nuances of Special and General Relativity? I am hardly proficient with the mathematics, but the big picture is very familiar to me - something to do with how a dyslexic thinks. ;-)
> [CP]
> Therefore, whilst our prior notions of space might be fairly complex, it
> seems to me that our a priori notion of time is in fact very simple. It is
> just the notion of succession. That time exists if there is a successor
> event to this event. I can imagine a succession of events that are
> repetitions of one another, and whilst I can agree that duration would not
> be measurable, that time might not be noticed, our a priori notion of time
> is not contradicted despite that.
[SPK]
The problem is that there can be no single unique "succession of events"! This is the point that I am trying to explain to you! Because observables obey such Principles as Heisenberg's Uncertainty, there can be to single a priori order of events that we can label with ever-larger Real numbers, starting at some Big Bang singularity point as our Zero. It is simply a mental picture that we carry around with us, part of our memories of precious events, all of the information of which is always and only in our "present moment".
BTW, this is something that the discussion of Observer Moments seems to be ignoring! A coherent notion of an OM must include some explanation of how one OM includes information about other OMs, which are its "history" within it. Is there some upper bound on the amount of information that any single OM can contain?
> [SPK]
> 'What is a "clock" if not an means to measure change?'
> [CP]
> A clock changes in order to measure time. Change is the measure of time, but
> is not necessary for time to occur. Changes do not occur just because time
> passes. Change is just necessary for measurement. I agree that time carries
> with it the possibility of change, but that is not the same. It cannot be
> both necessary and just possible, and the notion of change being a
> possibility entails that there is no contradiction in the notion of time in
> which there is no change.
[SPK]
No, sorry. That is wrong. Time is a meaningless notion absent the prior notion of change. This makes change priori ontologically to Time. When I state that Time is a measure of change, I am speaking generically. We obtain measures of the duration of some change by comparison to some other duration of change.
An old fashioned clock does this by mapping the revolutions of clock hands to the passage of the sun over head, just to pick out one of many interwoven mappings going on. ;-)
Your comment that there is a relationship between the "possibility of change" and time is on the right track, but again, there are many cases of changes that are fixed points. The apparent static Sun Dial vane's intransigence as the sun moves over heard being one; but look at the metal making up that vane with a powerful microscope and one sees nothing even close to a static system. As Lee Smolin wrote in his book "Three Roads of Quantum Gravity", pg. 53:
"The idea of a state in Newtonian physics shares with classical sculpture and painting the illusion of the frozen moment. This gives rise to the illusion that the world is composed of objects. If this where really the way the world is, then the primary description of something would be how it is, and change in it would be secondary. Change would be nothing but alterations of how something is. But relativity and quantum theory each tell us that this is not how the world is. They tell us - no, better, they scream at us - that our world is a history of process. Motion and change are primary. Nothing is, except in a very approximate and temporary sense. How something is, or what its state is, is an illusion. It may be a useful illusion for some purposes, but if we want to think fundamentally we must not loose sight of the essential fact that 'is' is an illusion."
It is ironic to me that Lee Smolin has had a very hard time following his own sage advice in his theoretics, for example see:
http://www.edge.org/3rd_culture/smolin/smolin_p2.html
The best solution that I have found is here:
http://www.kitada.com/timeV.html
> [CP]
> As to how we extract notions of transitivity from series of events, I would
> imagine it similar to how we extract notions of causation from sets of
> constant conjunctions.
[SPK]
Chris, the notion of a "series" has some kind of "greater than" or "less than" relation built in, or else it would not be a "Series". If we want to talk about collections of events, points, etc. that don't include transitive orderings in their defining algebra, we use sets, classes, categories, etc.
Set of constant conjunctions can be mapped to notions of causality, of course, that is because their include in their construction (the defining algebra) the property of Associativity and Commutativity.
http://en.wikipedia.org/wiki/Logical_conjunction
As I am trying to explain, if we are going to be faithful to the real world and the theories that fit it best, we must never ever assume that the events that make up out world of experience are associative and commutative with each other, except in very special situations.
> [SPK]
> 'Does a "history"" include values that can be associated with either of
> McTaggart's A or B series?'
> [CP]
> There is a strong argument to suppose it can be. The B series seems to carry
> all the information needed to judge truth conditions of reflexive statements
> such as 'event E is past' (from the A Series). The statement is true so long
> as it is occurs after event E. A B Series can then at least take a part in
> our conception of a history.
[SPK]
"Seems" is a very big caveat of a word! We have to be careful about the assumptions that we bring to the table. Your statement here seems to be consistent with what I am trying to explain, I do not understand the reason why you do not follow this point! Are you trying to argue for local realism without meaning to?
> [CP]
> What is needed is a sense of 'now'. A change of time rather than a change in
> time, a succession of events. So temporal becoming has to be invoked somehow
> - but also, it shouldn't be identified with conscious experience, there is
> no requirement for transitivity 'within the frame' so to speak. The danger
> with associating temporal becoming with our personal experience of time is
> that it is this that appears to deny time. To conclude that our experience
> of time is somehow fundamental to time itself, is to deny time exists when
> there is no observation of it.
[SPK]
We do indeed already have a "sense of now"! What we need is an explanation for why we can't avoid "being in it" and why the heck do its contents keep changing?!
The lack of transitivity "within the frame", is very important to notice! There are experiments showing that our conscious experience spans a duration of up to 1/2 of a second, there is some anecdotal evidence of very "long" present moment "windows" of in-transitivity. Anyone that composes music might has an idea of what I am talking about here...
But this "within the frame" window idea may be an artifact of how our brains work and not have any relevance to physics in general, but I remain agnostic about this idea.
> [CP]
> Are you not open to the charge you are levelling at others? Are you not at
> least partially a time denier?
[SPK]
Oh no, I am not a time denier. I am arguing that Change, no, Becoming, is a Fundamental aspect of Existence and not Static "Being".
I am, with Prof. Kitada, claiming that time is purely a "local" notion and that there is no "universal time" other that what obtains from synchronizations of "local times".
http://www.kitada.com/timeIII.html
> [CP]
> I accept that in a sense we always imagine time from a temporal
> perspective, that we can not leap out of the temporal view so to speak, but
> whether that should lead to a conclusion that makes experience of time
> fundamental is not so clear.
[SPK]
Ok, then notice that I am claiming that Change, not time (its local measure), is fundamental.
>
> [CP]
> I prefer to think that temporal becoming is in some way an objective
> property of time. I think of it as conceived by Aristotle, as the now that
> stays the same, as 'what is now' changes. We experience time as we do with a
> future past and present, because of the way time in fact is. Where I think
> computational models might break down regards what process they invoke to
> run the B series in order to stamp each event with future, now and past, -
> what is their incarnation of 'now' - and whether the adoption of such a
> process involves a pernicious infinite regress.
[SPK]
The pernicious regress only follows from the assumption that changes are some monolithic and universal monotonic aspect of the world. You might enjoy reading Barwise and Seligman's "Information Flow" - all kinds of neat (consistent!) uses of circularity and regress. Drop the assumption of well-foundedness!
Try this idea: We do NOT exist in a single space-time manifold. That structure is a collective illusion - but still a "reality"- that results from the coincidental synchrony of our individual observables. We -in ourselves, are not "classical" entities, we are quantum. It is our observations that are classical. This is the lesson that Everett discovered within QM and people have for the most part not yet understood.
Kindest regards,
Stephen
Received on Tue Jul 12 2005 - 10:06:07 PDT