[time 735] Which was first: clock or time?


Matti Pitkanen (matpitka@pcu.helsinki.fi)
Fri, 10 Sep 1999 08:43:37 +0300 (EET DST)


Dear Matti, Stephen, Hitoshi, et al.:

Because I am too busy with practical affairs to follow this discussion
closely, much less to participate actively, I apologize if the following
comment is inappropriate, but I could not let the following pass without
some comment:

Somebody (I think Stephen) wrote:

> I see LS's as fundamental clocks, and thus it
> should be possible to consider an "ensemble of clocks" as given by a
> ensemble of LSs. But, I am very sketchy in my thinking of this. :-(

To which Matti replied:

>
> [MP] I cannot say. One should need a quantative model for clock.
> Clock as oscillator is a nice model but based on the existence of
> time! You want to derive time from the existence of clocks, I
> am happy in deriving the existence of clocks from the existence
> of time!

My comment is this: Matti's reply does indeed identify the core issue.
The only problem I have with Matti's comment is that it seems rather
casual, so it doesn't alert the reader to how fundamental the disagreement
here is.

[MP] This was casual comment. I have talked a lot about TGD based
time concept in earlier discussions and I did not bother to repeat
all that. In any case, the disagreement is fundamental.

It is not that I would believe that geometric time is enough: the point
is that there are *three times*.

a) Subjective time "measured" as a number of quantum jumps occurred.

b) Geometric time, this is the good old Einsteinian time and combines
with space to form spacetime.
 
c) And also the time *parameter* t of unitary time
evolution operator U: this parameter is purely group theoretical and has
absolutely nothing to do with our psychological time. t runs from -inty to
infty during each quantum jump Psi_i--> UPsi_i-->Psi_f.
U defines S-matrix and predictions of quantum physics. Already Heisenberg
realized that the time evolution associated with S-matrix has nothing to
do with time evolution as we experience it. All calculations assume
that t runs from -inty to infty but take this as 'technical' assumption:
therefore TGD predicts precisely same general form of S-matrix
as standard physics. Interpretation is only different.

In standard physics all these times are identified as single time: it is
easy to understand what a mess results!

*************

In Hitoshi's first statements on the subject of Local Times one of the
things that attracted my attention (as a philosopher) was his comment that
the problem of time in contemporary physics is essentially a philosophical
problem, not a physical or mathematical problem. Matti's comment here
perfectly illustrates the validity of Hitoshi's assertion about the nature
of the problem of time. What is at issue is really how we understand the
fundamental nature of time. In our joint article in Apeiron, Hitoshi and
I were completely explicit about the fact that our position was in
opposition to the conventional understanding. Here is what we wrote:

 "...the proper clock is the local system itself,
and it is a necessary manifestation of that local system.
In this sense, “clocking” is the natural activity of any
local system. It follows from this that to be an existing
thing in the world necessarily involves clocking, without
which there is no interaction. In these respects, our position
is in complete opposition to the conventional understanding
of time measurement, where time is given a
priori and the measurement of time by clocks is viewed as
an incidental activity of intelligent observers. Contrary to
the conventional understanding, our view is that all beings
are engaged in measuring and observing, and the activities
of measuring and observing are not incidental, but
pertain to the essence of all interactions. If we are permitted
to express it somewhat boldly, we have turned things
completely around: It is not that things exist and their
duration is incidentally expressed by clocks. According to
our formulation, clocks exist and their operation is necessarily
expressed by duration."

(to which we might have added, Time, as measured or counted duration, is
what results when certain local systems or certain sets of interactions
are chosen as the standard in terms of which other durations are
described, much as monetary value comes into existence when one commodity
is chosen as the unit in terms of which the exchange relations of other
commodities are expressed.)

[MP] Thank your for a nice phrasing of your viewpoint.
 I agree in many aspects with what you say. I have however
'neuropsychology' oriented starting point. LS as self, if it experiences
time must have subself waking up periodically. We have a lot of
them, typically mental images representing mental images, recur
periodically. After images are a good example. Self can
however be in state of whole body consciousness and have no subselves:
in this case it has no clock: hence explanation for the reports about 'no
time' experiences by meditators.

I could paraphrase you comment about turning things completely around.
Selves exists as heaps of cs experiences associated
with quantum jumps and give rise to experience of *subjective time*.
Each self waking up periodically is clock of some larger self.
One could also say that quantum jump is basic tick of subjective
time (not directly experienced as such however) and subjective time
is created by the syncronized ticking of all the subjective clocks of
this infinite universe. But as I said, I assume also the existence of
geometric time and formal time parameter t associated with the unitary
evolution operator U. I believe that only this 'holy trinity' makes
it possible to resolve all the paradoxes related to the concept
of time.
********

Now, to come back to Matti's comment: It is entirely in order to
challenge Hitoshi and me to flesh out our claims -- to show that we can
offer an intelligible and serviceable, quantitative model of a clock --
and it is particularly apt for Matti to demand that we show that our model
is not an instance of circular definition. However, I am less comfortable
when Matti says, "I am happy in deriving the existence of clocks from
the existence of time!" The reason I am uncomfortable with that is that
it seems to me that it simply begs the question. I am not saying he is
wrong. I am simply saying that we need to acknowledge that this is what is
in dispute. From our point of view, Matti's claim looks just as doubtful
as ours looks to him.

[MP] OK. My statement was casual already because I have
all these three times instead of only one (as if single time would
not produce enough head aches(;-)) and was meant only to
pinpoint the difference in views.

Best,
MP



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