Re: A Geometrical Proof of the Non-invariance of the Spacetime Interval

[Hugh Haskell <hhaskell@MINDSPRING.COM>]

At 17:21 -0800 1/20/03, David Rutherford wrote:
> (4) If you had breakfast in Los Angeles and lunch in San Diego, would
> you really tell _anybody_ that you had breakfast and lunch in the
> same place?
That depends entirely upon whether you are in the same reference
frame as Los Angeles and San Diego (which I assume are in the same
reference frame--at least most of Los Angeles is on the same tectonic
plate as San Diego is).

If my frame of reference is a uniformly moving train that passes Los
Angeles at breakfast time and San Diego at lunch time, then I can
easily say that I had breakfast and lunch in the same place--the
dining car. If I have to stop and get off the train in LA and San
Diego, then SR doesn't apply and the discussion is pointless.

Someone watching me from, say, San Clemente, can say that I had
breakfast when my dining car was in Los Angeles and lunch when my
dining car was in San Diego.

Beyond that, I frankly don't understand the point of this thread,
which is why I haven't participated up to this point.

Hugh
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Hugh Haskell
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<mailto:hhaskell@mindspring.com>

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