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(SR) Lorentz t', x' = Intervals
Section - 4. The 'just coordinates' argument

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The 'just coordinates' argument is so patently ridiculous
that even opponents have a hard time accepting just how
simple and obvious its debunking can be, as shown in this
section.  However, further sections take a more arithmet-
ical approach that you'll maybe find more professorial.

The 'just coordinates' argument is that t is mot a
duration, not a time interval; it's just an arbitrary
clock reading.  But what if the moving system observer
comes speeding by while you make your annual 'spring
forward' or 'fall back' change?  The formula says that
the moving system clock's 'just coordinate' reading 
can be calculated from yours:

      t' = (t - vx/cc)/sqrt(1-vv/cc)   (Eq 1t)


Imagine the moving system oberver's confusion if his 
clock changes its reading while he's looking at it!  

If his clock doesn't change when yours does, the formula 
is wrong;  if it is truly a 'just coordinates' formula. 

And then what happens if you realize you were a day 
early and put your clock back to what it had said 
previously?

And suppose you are in NYC and your twin in LA and
both are watching the moving observer. You'll both be
using the same v because you are at rest wrt (with
respect to) each other. You're on Eastern Standard
Time and your twin is on Pacific Standard Time
maybe. You have three hours more on your clock than 
does your twin. 

On which 'just coordinate' clock will the Lorentz 
transforms base the 'just coordinate' time the moving 
system clock says?  The formula applies to both of
your t-times:

      t' = (t - vx/cc)/sqrt(1-vv/cc)   (Eq 1t)


Sure, the idea that you can change someone else's
clock with no connection of any kind is really 
ridiculous, but Eqs 1x and 1t aren't MY equations. 
Are they yours?  And we aren't the ones to say x, t, 
x', and t' are just coordinates.

If the t' formula is actually either an elapsed
time formula, or the basis of a t'/t ratio, then
there is no implication that one clock's reading
has anything to do with the other's. 

It can only be rates of clock ticking, or how one 
time INTERVAL compares to the other that the formula 
is about.

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Top Document: (SR) Lorentz t', x' = Intervals
Previous Document: 3. The Lorentz-Einstein transforms
Next Document: 5. Single-system, little-purpose ambiguity.

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Last Update March 27 2014 @ 02:12 PM