Re: The train and the light inside.


PD wrote:
tomgee wrote:
Spaceman wrote:
"Igor" <thoovler@xxxxxxxxxx> wrote in message
news:1140550474.168851.260960@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
And when did you do your experiment that proved that they don't measure
the same speed c?

The problem is, how could they?
An outside observer could not measure
c for what an inside observer is measuring c for already.
the relative speeds are being ignored if such is true.

It seems that way to you, but I contend that the outside observer has a
faster time rate than has the train because the train is moving faster
than he is,

How do you know that, tomgee?

The same way you know that, PD, since I have told you how over and
over. It's very simple and undeniable. When two objects are at
constant velocity wrt each other, they must be moving at the same speed
and in the same direction. Thus, you and your TV are at CV when you
sit and watch it. However, when you get up to go pee, during the time
you are moving, you are not at CV wrt your TV. Then, you are moving
faster than your TV because at CV both of you are at CV with the planet
also, but when you move, you are moving faster than the TV and the
planet too. The TV and the planet remain at the same speed and moving
in the same direction so they remain at CV wrt each other. But not
you. Once you move from your seat, you are no longer at CV with the TV
and the Earth because you are no longer moving at the same speed and in
the same direction, but now you must move slightly faster than the two
in order to get somewhere else (your potty) and return later to the TV.

During the time you went off and returned, time for you passed slightly
slower than it did for your TV and the Earth. Meaning that you aged
slightly less than did your TV or the planet. I know it's hard for you
to believe all this, but it's based on SR and the second law of
thermodynamics.

If it so happens that the train is
traveling west, then I think I can argue that the train is traveling
*slower* than the fella on the tracks. Do you see why?

Assuming the experiment declared a certain direction in which the train
is moving, the experiment did not depend on the direction at all since
the two observers were not said to be at CV wrt each other. Direction,
then, does not enter into the experiment, only the fact that one
observer is moving faster than the other.

If you wish to say that due to the rotation of the planet wrt the Sun,
the Earth is traveling westward, again, direction has no meaning here.
The OP made a point of the light moving from one end of the train to
the other, and I pointed out that my example has the light moving from
the ceiling to the floor, meaning that direction is not relevant here.
It is only the fact that one object is moving on the surface of the
planet and for it to do that, it must move faster than the planet moves
in its state of motion.

That includes the Earth's speed through space and its speed of
rotation. For you to go pee, you must move slightly faster than the
speed of the Earth in space in order to get to a different location on
Earth.

so then the light must travel at c because of empirical
evidence, but the _distance_ the light travels is less for the
passenger than it is for the outside observer. To explain this
requires that we accept the fact that c is invariant (at least locally)
and so we cannot change c, we can only change the time rate accruing to
each observer in order to explain the fact that the light speed for
both observers is indeed c.

In my train experiment, a single photon particle falls to the floor
from a ceiling lamp, instead of moving horizontally. No matter,
though, since we cannot change c, it is time that varies.

.

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