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Hi
Judith,
I think we are
indeed each looking of time in somewhat different ways. As do you, I do not
think time is "merely a figment of collective human imagination". Not entirely,
anyway. To me, time is the observer-imposed relation of changes in some
physical clock system as a reference system to changes in
some physical system under study.
What I see in ch.
4 ("The Encoding of Time") of AS is primarily the exploration of dynamics
and logical time as a way of exposing the notion of "time" as not being a
true physical quality; but, rather, a quality of the type I mentioned above.
To me, the dilemma
of "time" is that it is inherently about the relations between changes in values
of observables of multiple systems, and therefore we cannot study this relation
except by comparison of two (or more) such systems. In a sense, we have no
way to speak of changes in the material world except in reference to other
changes in the material world. This is, of course, just the frustrating
restriction due to not belonging to a universe we can make
fully objective, and one in which we can deem no particular source of
change as being regarded as 'the' universal and fundamental measure of
change in the universe.
Regards,
Tim
Hi Tim,
What you are still talking about with my father's
written reference is "what time isn't", according to him. The pages you
referenced are a discussion of our "perceptions of time" which is not the
same thing as a discussion about time. (A better area for a very
preliminary look at time with that book is in Chapter 4-- But even there, he
talks more about how time can be treated in formalisms, how our perceptions of
time can often contradict one another, the difference between logical time and
dynamical time, etc). His point was that clocks don't measure anything
except "perceived time"; they give us reference points for other
things, activities, changes, incidents, etc) therefore what we perceive
as "time" in that sense is really a mental construct of a set of labels.
He never said that time itself is a mental contruct. He did not believe
that.
Perhaps you are thinking of time in a different
way from the way I do. My perceptions are more about times effect on other
things. That may be the only way we can study it. I don't necessarily
think that time is a separate and separable "thing" from the rest of
reality, but neither do I agree that time is merely a figment of
collective human imagination. I believe my father saw time as one
integral aspect to complexity. He didn't specifically address the subject, I
believe, because it was a "given" and therefore not something that he needed
to define in order to develop the framework of ideas that describes
complexity. However, in developing those ideas, especially the anticipatory
systems stuff, he began to see some very peculiar behavior in what he called
"time"-- peculiar because it defied all current "rules" by which it was
perceived to operate. Most scientists that I've met have never even addressed
any of these issues. If the list knows of some intelligent written work, I'd
be interested in seeing it.
Judith
PS: I've read the Paul Davies book on time
already.
----- Original Message -----
Sent: Tuesday, October 21, 2003 5:28
PM
Subject: Re: [ROSEN] Time and
context
Hi
Judith,
See
interposed.
Regards,
Tim
Interesting stuff, Tim. What my father said in
the passage you referenced about time was more a discussion about what we
don't know, than a discussion about what we CAN know.
To
me, what your father said about "time" in AS pgs. 50-51 did seem to me
to say 'what is time'. He says near the end of those pages, "If
we take the familiar step of imputing relations between percepts to
corresponding relations in the external world, the above considerations
suffice to characterize time in that world." That seems pretty direct to
me.
And
once one accepts those considerations he gives, then the notion of "time"
is just the use of a system to generate labels which have no special
import or significance on their own: "a clock does not "measure"
anything; it simply exemplifies the mentally constructed relation of
simultaneity between percepts in a particularly convenient form."
Or, as Mach says, time is just an abstraction.
In
his view, biology was already telling us things about time. What
biology was telling us is that time is very much more than a clock
suggests. It is not linear and it is not unidirectional and it is not a
constant rate, unchanging. If anything, his observations suggested that
there may be no such thing as "rate" with time, only with how
material systems relate TO time. Now do you see why I was so
anxious for him to really focus his attention on this and see what
developed?!
Maybe we are using different language. To me,
"time" is this abstraction constructed from the relation of percepts and
labels. Since it is an abstraction and not physical,
it deserves no further explanation. Certainly, acknowledging that time
is an abstraction means that the idea of a linear "dimension" of time, for
example, is but an abstraction that has no physical basis as a
preferred formal representation.
But I am reluctant to say that "time" is
therefore not linear or not unidirectional, etc. since to me the word
"time" refers to any kind of situation where one
natural system is considered to generate temporal labels which are
represented in some formal representation. Such a system could be
linear and uniform, or it could be nonlinear or perhaps,
non-unidirectional.
To me then, "time" does not refer to a singular
kind of quality in Nature to be studied, but rather refers to the
entire class of relations between systems where we have
subjectively promoted one of those systems (and one or more of
its observables) to be the generator of time-labels. And no member of
this class has preferred status as representing something more fundamental
about the physical world than another.
So, then, I see
the exploration of "time" as the exploration of this class of relations.
Heretofore, we have historically been interested in very mechanistic kinds
of timeclock systems. But a broader view of this whole class of relations
which constitute "time" would include such time systems that
are linear, nonlinear, unidirectional, not unidirectional,
and so on. [Note that even the designations 'linear',
'nonlinear', etc. must be by comparison to some other natural system.
Along the lines of Mach, to ask whether a timescale is linear or not
in itself is a senseless
question.]
To me, the
question is: Since we can subjectively choose any system and
any of its observables as the time-label generator, which kinds
of clock systems might be useful in modelling complex (especially
biological) systems? And are there instances when it is fruitful to use
combinations of more than one clock system in order to model
complex systems?
His
work up to his death really only illuminated that time wasn't what
Einstein was defining, or at least that's not ALL it is. My father's
work showed us what time ISN'T, but he never got around to seeing if
he could sort out anything else about what it IS.
However, he did leave the door wide open for
others to follow, using the unique perspective he discovered that
biological organisms have afforded us if we look at it from
that perspective. In the book, Mind Over
Matter, that I had started to write on Rosennean ideas
(which generated the now-infamous "Levels of Complexity" that caused
such a kerfuffle on the other list), I compared the kind of perspective
change my father achieved to the change in perspective that
allowed Copernicus to see that the Earth was not a flat place at the
center of the universe. The reason the sun came up in the east and set in
the west in an orderly way wasn't because Apollo (as one example) was
a punctual sun god who showed up for work on time every day to drive his
chariot across the sky, or some other equally reasonable explanation that
made "sense" to the folks up to that time. How strange it must have
sounded to those people to hear the suggestion that the reason the sun
rose in the east and set in the west was because it wasn't moving at all,
WE WERE. That the Earth was a round ball, floating, suspended
in vast, empty space-- spinning (on an imaginary central axis) in such a
way that the sun, which doesn't move at all in relation to
us, looks like it's rising in the
east and setting in the west.... and then the further explanations that
developed; that the planet is tilted on its imaginary axis, that it isn't
just spinning but also moving through space in a wide circle around the
sun, which is what gives us the seasonal change every year.... I mean, it
sounds crazy, doesn't it?
Judith
----- Original Message -----
Sent: Tuesday, October 21, 2003 11:13
AM
Subject: Re: [ROSEN] Time and
context
> Continuing my thoughts on time....
>
> I've been
pondering how else one might encode our dynamical universe other
>
than by a 3+1 dimension system of space+time. At the moment, I can't come
up
> with an alternative.
>
> I keep coming back to :
what is our basis for "time"? And it seems to be
> that it rests on
having some natural system (call it C) to act as a clock
> with one
or more observables {c1,...,cn}, and it is the measurements of
such
> an observable(s) which (when they generate distinct values)
serve as labels
> of time. We have no way of considering "time"
other than by choosing some
> system to act as C and choosing
certain of its observables to act as the
> {ci}, and choosing
certain of the equivalence classes of those measurements
> of the
selected observables to serve as the "ticks" of time, and the
>
relations between those ticks to serve as the "units" of time.
>
> (This is essentially also how Rosen describes it. As an aside, it
also
> appears that Aristotle had a roughly similar view of time
[Physics IV.11] ,
> where he states that "For that is what time is:
number of change in respect
> of the before and after. So time is
not change but is that in respect of
> which change has a
number." Except that for Aristotle, what he calls
>
"numbering", rather than being merely labels, becomes identified with
points
> on a line, and rather than this numbering scheme and the
associated line
> being merely abstractions, seems to have for
Aristotle some real meaning:
> "It is manifest then that time is a
number of change in respect of the
> before and after, and it is
continuous, for it is a number of what is
> continuous". This notion
of the infinite continuous also leads him in the
> next section to
his proposal for an "unmoved mover" - a first cause.)
>
> In
this way, time is a rather arbitrary concept: it consists of a
>
subjectively chosen relationship between two or more natural system,
one
> being C, the clock system, and S (or {Si}), the system(s)
under study.
>
> It then occurred to me that our penchant for
"equal units" of time is,
> accordingly, also quite arbitrary since
our choice of the clock system C is
> arbitrary. Rather than choose
one second as "the period equal to
> 9,192,631,770 cycles of the
radiation which corresponds to the transition
> between two energy
levels of the ground state of the Cesium-133 atom" as the
> NIST
does, we could just as well have left it to be some fraction of a
solar
> day. Because of variations in the solar day, the latter
would mean that the
> meaning of one second would then vary as
well.
>
> There is nothing erroneous about the latter choice,
it simply seems to us
> cumbersome. Our preference for mechanistic
systems leads us to find some
> system C like the NIST definition
which is 1) context independent, and 2)
> has its basis in the
microscopic. The latter is, I think, also part of a
> reductionist
viewpoint as well: the idea being that if we could just find
> the
most fundamental unit of time on the most fundamental microscopic
level
> of physical reality then we will find that all other more
macroscopic
> measures of time will be some multiple of this
"primitive" unit of time. In
> this way, perhaps a reductionist
hopes to not only reduce matter to some
> proposed fundamental
entities, but also achieve a similar reduction of
> dynamics on the
basis of a proposed universal fundamental unit of time.
> (This
leads me to wonder if measuring/modelling the dynamics of
biological
> systems, or complex systems in general, would benefit
from the use of
> non-mechanistic clocks, which may have unusually
varying and unequal "units"
> of time.)
>
> But if
reductionism is false, then we cannot give any particular system C
a
> preferred status. There is no truly objective character to time.
In this
> way, we ought not make statements such as "the 'now' is
always emerging",
> because such a statement presumes a god-like
objective perspective of
> reality where time is endowed with
metaphysical meaning beyond our reference
> to some subjectively
chosen physical local system C. "Now" only has meaning
> with
reference to some observer with some clock system C (which may be
a
> system internal to the observer).
>
> Mach
similarly says in "The Science of Mechanics":
> "Nay, we may, in
attending to the motion of a pendulum, neglect entirely
> other
external things, and find that for every position of it our
thoughts
> and sensations are different. Time, accordingly, appears
to be some
> particular and independent thing, on the progress of
which the position of
> the pendulum depends, while the things that
we resort to for comparison and
> choose at random appear to play a
wholly collateral part. But we must not
> forget that all things in
the world are connected with one another and
> depend on one
another, and that we ourselves and all our thoughts are also a
>
part of nature. It is utterly beyond our power to _measure_ the change
of
> things by _time_. Quite the contrary, time is an abstraction,
at which we
> arrive by means of the changes of things; made because
we are not restricted
> to any one _definite_ measure, all being
interconnected. A motion is termed
> uniform in which equal
increments of space described correspond to equal
> increments of
space described by some motion with which we form a
> comparison, as
the rotation of the earth. A motion may, with respect to
> another
motion, be uniform. But the question whether a motion is _in
itself_
> uniform, is senseless. With just as little justice, also,
may we speak of an
> "absolute time" - _of a time independent of_
change. This absolute time can
> be measured by comparison with no
motion; it has therefore neither a
> practical nor a scientific
value; and no one is justified in saying that he
> knows aught about
it. It is an idle metaphysical conception." [ch. II.VI.2]
>
>
Regards,
> Tim
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