Re: The velocity of light going pass a moving train.

On Jun 21, 12:58 pm, bz <bz+...@xxxxxxxxxxxxxxxxxxxx> wrote:
Dono <s...@xxxxxxxxxxx> wrote in news:1182450172.908373.143140
@a26g2000pre.googlegroups.com:

Correct, the beam hits the center for the train observer but does not
for the track observer. The reason is that the mirror has moved to the
right while the beam travelled from the floor to the ceiling.

You are ignoring the fact that the trackside observer MUST observe the beam
hitting the mirror in the exact same place that the observer on the train
sees it hit.


No, this is where we disagree. There is no reason for this "must"
other than your statement. Remember the situation with the two flashes
travelling horizontally? (the exercise that disproves absolute
simulatneity)? This situation is similar, you are letting your
"feelings" drive you. The math contradicts what you "feel"


Take a bead on a rod, going from floor to ceiling. Bead moving up and down
rod at constant velocity of 1 ft per second. Train moving at 1 ft per
second.
rod ten feet long.

Bead travels 10 feet horizontally and 10 feet vertically in 10 seconds,
from trackside observers viewpoint.
Bead travels 10 feet vertically in 10 seconds from train observer's view
point.

Bead can not leave rod. Bead's velocity is different, as measured by
observer in train and trackside observer. Angle of path is different for
different observers. Bead still does not leave rod.

Bad analogy. I think this is the root of your problem. The rod
constrains the bead by transporting it . Light is not constrained. The
other problem is that you seem to keep missing the fact that the train
"slides" from under the light beam, i.e. it seprates away from it.



Same for light clock one light nano second tall.

Light can not leave its vertical path, no matter if train is stationary or
moving at .999996 c.


Surprisingly, we are in agreement hon this issue. But the train slides
away while the light beam travels (vertically) so, the beam would
leave a trace inclined to the left (see my previous picture to you)
with respect to the rear pannel of the train. This is the root of the
disagreement.


What varies is the TIME it takes to travel the path, and the length of the
path in the trackside observer's iFoR. The light still hits center of top
mirror. Different observers see the light move different distances. Their
clocks show different time for the transit. But all measure the velocity of
the light at c, using their own clocks, rulers, etc.

--

Yes, of course they all agree on the speed being c and they disagree
in terms of the time taken. Look, the disagreement I had with Jeckyl
(and now, with you) is not about the absolute value of the angle, is
about the sign. I maintain that light "appears" inclined towards the
rear of the car, Jeckyl (and now , you, if I understand correctly)
claim that light "appears" inclined towards the front of the car.

.

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