time dilation terminology

Michael Andre-Driussi · 03 Dec 2002, 00:30 · from urth-v0212.mbox · original

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From: Michael Andre-Driussi <mantis at siriusfiction.com>
Subject: (urth) time dilation terminology
Date: Mon, 2 Dec 2002 16:30:33 -0800
Message-ID: <urth-v0212-2334 at digest.urth.net>
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Blattid wrote:
>Um, no, Mantis ... in a world that obeys Einstein's rules,
>"time" is equally [ob|sub]jective in any inertial reference
>frame; more specifically, "time" on the Whorl cruising at
>NAFAL velocities is no more and no less objective than "time"
>on the surface of Urth. This is a consequence of "time" not
>being an independent entity in such a world; it is one
>dimension of a four-or-more-dimensional manifold which we
>(more) properly refer to as "spacetime."
>
>The "objective time"/"subjective time" terminology you use
>comes, not from relativistic physics, but from SF writers
>who play with these concepts in their novels but either
>do not comprehend what I oversimplify in the previous
>paragraph, or else assume (and I think this quite likely)
>that most "users" of NAFAL ships would think this way, the
>non-absolute nature of spacetime in an Einsteinian universe
>being kind of difficult to wrap one's head around. (I do
>not claim to have my head all the way around it by any
>means!)
>

Unless you are trying to tell me that there is no time dilation at
relativistic speeds, which would be an interesting claim, then this looks
to be another flea circumcising exercise on the terms Objective and
Subjective.  Worthy of litcrit, and literary theory, and philosophy (where
these terms are Big Terms indeed).

As I was using it,

"Objective time"  =3D t(o) =3D "interval of time experienced by an observer=
 in
the coordinate system (at rest)"

"Subjective time" =3D t =3D "time recorded by a clock moving in the rocket =
at a
constant velocity V across space"

c =3D "velocity of light in a vacuum"

t =3D t(o)/Square root(1-(V^2/c^2))

Would you prefer I use "t" and "t(o)" instead of Subjective and Objective?
I mean, criminy, you make it sound like I'm selling the Dean Drive here!
Gimme a break!

=3Dmantis=3D



--=20

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