Re: If

Every observer sees their own frame uncontracted.
It is only moving objects which appear contracted.

Consider this.

A giant stick is flying past you, marked off with distances.

The distances on that stick are now length contracted.

You see two objects attached to the stick--one moving away and one
moving toward you.

Due to the doppler effect or simple calculation of where the object is
compared to where the image must appear, the object moving toward you
appears to be moving superluminally. It's actual "current" position of
the object is MUCH closer than the image.

On the other hand, the object moving away can be no further away than
twice as far as the image.

Suddenly you accelerate, matching pace with the stick. You are
accelerating TOWARD the object that is moving away.

The stick is no longer length contracted.

The distances to both objects has suddenly increased.

You will see the same light both before and after the acceleration.
However, the wave front has changed shape. The sphere of light coming
from the object you've moved toward has GROWN (making it appear to be
further away which it actually is.), while the sphere of light from the
object you've accelerated away from has SHRUNK, making it appear to be
closer to you (which it actually isn't).

Some clue of this shrinking/growing effect is shown in
http://www.spoonfedrelativity.com/files/newYears2.swf
http://www.spoonfedrelativity.com/files/acceleration4.swf
and
http://www.spoonfedrelativity.com/files/ninephotons.swf

Anyway, I think I've got off topic here, as usual, but the main point
is that you should always feel that your own frame is uncontracted.

.

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