On 6/15/2025 4:48 AM, John Clark wrote:
On Sat, Jun 14, 2025 at 11:42 PM Alan Grayson <[email protected]>
wrote:
*...*
*>> do you have a better definition of time than "what a clock
measures"? I don't. *
/> Sure; time is caused by the existence of observed events.No
events. No time. Nothing to do with clocks, AG /
The events have to be time-like separated, i.e. "at the same place" in
some reference frame.
*An eventis defined as a specific space in 4D spacetime and a specific
_TIME_. So if you use time in a definition of time you get into an
infinite regress. *
*>> If it was impossible to make a clock, if nothing occurred
in a periodic manner, then the concept of time would be
meaningless.*
/> A clock doesn't have to be periodic. It can be linear. It just
needs to assign a unique real number to each event being
observed. AG/
*So you think a clock could be madeby making a list of the position of
every particle in the universe with respect to time, *
I doubt AG thinks that. But linear clocks are not unusual in thought
experiments. Gallileo showed that balls rolling down an inclined plane
could be used as a clock.
*but without a clock how do you know what time it is? And even if you
could somehow manage to make such a list, how could you know which way
to read it? We can tell which way the arrow time is pointing because
tomorrow will have more entropy than today, but that would no longer
be true when the universe has reached heat death and entropy has risen
to a maximum. *
*>> The 4D shape of the resulting spacetime is determined by
how the matter/energy is distributed, and its precise shape
can be calculated with Einstein Field Equations, which uses 4D
non-Euclidean tensor calculus. *
/> What's obviously lacking is a physical mechanism to get to your
conclusion. AG/
*My problem is I don't know what sort of explanationwould satisfy
you.Give me an example of a phenomenon, _ANY_ phenomenon physical or
otherwise, that you feel has a satisfactory explanation and doesn't
generate additional questions that are very obvious. *
/> Insofar as you defend the Gospel, and vehemently I might add,
although at some level you don't think GR is the end of the road,
but emotionally you do. AG /
You know very well since I've posted it repeatedly that GR isn't the
"end of the road" because it is inconsistent with quantum mechanics and
it predicts unphysical infinities in many cases.
Brent
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