Lester's overlapping bodies and frames in SR

This is being reposted as my previous reply did not
make it past my ISP. It should appear as a new
thread as Lester intended.

"Lester Zick" wrote in message
...

Jeff Root:

I get what you are arguing: The amount of contraction seen
in an object at a given point in space is different for
observers moving at different speeds relative to the thing
being observed. And that seems self-contradictory.

Not quite, Jeff. Let me show you an example: We have two interstitial
bodies traveling at different velocities with overlapping geometric SR
frames of reference, AF and CD which align in the following way:

A--------------(C---v2------D)------v1-----------F

In the above diagram:

1) which parts represent the "two interstitial bodies"?

2) "interstitial" means in the gap between something, what
are the bodies between and what represents those items
in the diagram?

3) What are the "different velocities" of the two bodies?

4) You say "AF" and "CD" are names of your frames but have
shown the letters "A", "F", "C" and "D" as separated.
What does that signify?

5) You show lines of "-" with "" and "" which seem to
imply vectors with associated values "v1" and "v2". Are
the start points "A" and "D" then to be taken as the
origins of the frames "AF" and "CD" respectively?

6) Are the vectors from A to F and from D to C:

a) displacement vectors of two objects moving from
location A to F and from D to C in the respective
frames?

b) velocity vectors of the frames themselves and if so
i) are "v1" and "v2" the velocities of the frames
ii) in what third frame do AF and CD have those
velocities?

c) indications of the sense of one of the axes of the
frames since you say they "align in the following
way" (e.g. do you mean the X axis coordinates in
frame AF increase to the right while those in CD
increase to the left)? If so, shouldn't the second
frame be named "DC" for consistency?

And different MM type experiments are conducted across CD and across
AF by observers in each frame of reference at the same time.

These do not appear to be shown in the diagram. Please add
them and label the arms so we can discuss them more easily,
or at least add the arms that lie in the direction shown in
the diagram (I hope we can assume there is no need to represent
the transverse arms for this discussion).

But since
the velocity of AF is different from the velocity of CD different
contraction factors would have to apply to each. However because AF
and CD overlap one another in space this cannot be.

Untrue, the factor depends on the speed of the object
relative to the observer so there is no problem. However,
this will be easier to explore when you clarify the
ambiguities in your diagram.

George