Re: [ANN] SR/InertialFrames v2.2.1

On 05/24/2025 08:21 AM, Julio Di Egidio wrote:

On 24/05/2025 16:48, Ross Finlayson wrote:

On 05/21/2025 04:47 AM, Julio Di Egidio wrote:

>

A clock hypothesis: is a pretty usual idea, that there
are no closed time-like curves and furthermore that whatever
meets has whatever clocks meet. Einstein called it a, "the time",

>
That's false on all accounts, including the time travel
side of things, you still cannot get your head around
which, apparently.  That said, thanks for asking:
>
The "clock hypothesis", in simple terms, is the principle
that all working clocks tick at the same rate (the proper
time rate) in their own frame.  Drop that and you drop
any chance of doing any physics at all: together with
the use of light signals, clocks are fundamental to
contemporary physics and the very measurement process.
>
It is also equivalently the hypothesis that the local
experience of time is universally the same for every
particle and every observer: and I do not actually
mean anything psychological, rather the rate of getting
old, just like the rate of atom decay, is a physics fact.
>
And note that none of that is about inertial frames and
motion only: time proper ticks at the same rate every
time every place.  Indeed, time dilation and length
contraction are only relativistic effects, we know that,
don't we? "Nothing is actually slowing or shortening
aboard that ship", which remains canonical relativity.
>
-Julio
>

Ah, no, "clock hypothesis" is usually that there's
a, "universal time", for example an Einstein's "the time".
The measuring rods and rigid connections and material points
of contents in space and the universal parameterization of
the entire differential-system (or integral-system) of an
inertial-system (instead of a momentum-system), has that
time (usually "t") is indeed a sort of universal thing,
that as with regards to a clock hypothesis saying it's
monotone, constant, and strictly increasing, and everywhere,
results it's the same to say it's also universal.
The "space-contraction" as "time-dilation" and "length-contraction",
_always together_, helps establish that there are all sorts
Lorentzians like FitzGeraldian, Maxwellian, Einsteinian, Fresnelian say,
a bunch various sorts Lorentzians, then.
Mostly it's a FitzGeraldian space-contraction.