On May 11, 7:42Â*pm, xxein wrote:
On May 7, 8:11Â*pm, rbwinn wrote:





On May 7, 3:54Â*pm, " wrote:

On 7 mayo, 18:46, rbwinn wrote:

On May 7, 1:11 pm, PD wrote:

On May 7, 1:45 pm, rbwinn wrote:

On May 7, 10:40�am, PD wrote:

On May 7, 11:25�am, rbwinn wrote:

Well, no, if lightining strikes the front and rear of a moving train,
leaving marks on the train and the track, the marks on the track will
be the length of the train apart, which relativity of simultaneity
cannot explain.

Sure, it explains it.

Here's how:
The track observer goes back after the train has passed and notes that
the marks on the track are 400 m apart. Remember that, for the track
observer, the strikes hit simultaneously. Since the marks are also on
the train, the track observer correctly notes that the train is 400 m
long. (This is what a length measurement entails anyway: marking the
locations of the ends of an object at the same time.)

Now the train observer goes back after the strikes have hit and notes
that the marks on the train are 500 m apart. But it's also true that
this observer saw the front strike happen before the rear strike ---
the strikes are not simultaneous in this frame. So it doesn't bother
this observer at all that the track observer sees the marks 400 m
apart. That's exactly what you'd expect if you marked the location of
the front of a moving object before you marked the location of the
rear of the moving object -- and that's exactly what the train
observer is sure happened.

The length of the train is frame-dependent. Whether the marks at the
end of the train were made at the same time, is also frame-dependent.

Does this help you understand?

The train has an actual length.

No, actually, it does not. Length is a frame-dependent quantity. The
value in one frame is no more "actual" than the value in another
frame. Now, there is a "rest length" which is the length measured in
the frame in which the train just happens to be at rest, but there is
nothing preferential about this frame.

Well, no, length is not a frame dependent quantity. Â*Length is
length. Â*There is no distance contraction.
Robert B. Winn

Says who?
And what does that have to do with relativity of simultaneity?
Einstein is quite specific in describing the situation in his book:

"Are two events (e.g. the two strokes of lightning A and B) which are
simultaneous with reference to the railway embankment also
simultaneous relatively to the train? We shall show directly that the
answer must be in the negative."

So you see, he is talking there about time relations of events, not
about length contraction. And sure enough length contraction is quite
real and measurable.

No, sorry. Â*I say. Â*And I can prove it. Â*There is no relativity of
simultaneity, and there is no distance contraction. Â*The Galilean
transformation equations show that both of these concepts exist only
in the imaginations of scientists. Â*Scientists claim that they have a
clock in the frame of reference fo the train, which has a rate of

Â* Â* Â* Â* Â* Â* Â* Â* Â* t'=(t-vx/c^2)/sqrt(1-v^2/c^2)

Now with regard to the Galilean transformation equations, the variable
t' is already used in the equation, t'=t. Â*So to use this value that
scientists say is the time of the clock on the train, we have to
change the variable from t' to n'.

Â* Â* Â* Â* Â* Â* Â* Â* n'=(t-vx/c^2)/sqrt(1-v^2/c^2)

Â* Â* Â* Â* Â* Â* Â* Â* t=sqrt(1-v2/c^2)n' + vx/c^2

Now, as you may recall, t'=t, so

Â* Â* Â* Â* Â* Â* Â* Â* Â*x'=x-vt
Â* Â* Â* Â* Â* Â* Â* Â* Â*x'= x - v[sqrt(1-v^2/c^2)n' + vx/c^2]

All you have is a clock running at a different rate than the clock in
the frame of reference of the track. Â*Other than that, the train,
bolts of lightning, and motion of the train happen the same as shown
by these equations.

Â* Â* Â* Â* Â* Â* Â* Â* Â*x'=x-vt
Â* Â* Â* Â* Â* Â* Â* Â* Â*y'=y
Â* Â* Â* Â* Â* Â* Â* Â* Â*z'=z
Â* Â* Â* Â* Â* Â* Â* Â* Â*t'=t

The bolts of lightning strike simultaneously in both frames of
reference. Â*The flashes of lightning are seen at the same time by the
observer by the track. Â*The flashes of lightning are seen at the same
time by the observer on the train.
Â* Â* Â*The transmission of the light happens according to these
equations:

Â* Â* Â* Â* Â* Â* Â* Â* Â* Â* x=ct, in the frame of reference of the track

Â* Â* Â* Â* Â* Â* Â* Â* Â* Â*x'=cn' in the frame of reference of the train.

Â* Â*The value of n' is actually n'=t(1-v/c), not t' from the Lorentz
equations, but we were using the Lorentz equations value so that
scientists could see them used with reality for the first time in more
than 100 years. Â*A clock running at the rate of the Lorentz equation
value is running slightly faster than a clock which shows light to be
traveling at c in the frame of reference of the train.
Robert B. Winn- Hide quoted text -

- Show quoted text -

xxein: Â*For once you accidentally got something correct. Â*There is no
distance contraction in SR. Â*It is length contraction of a physical
body of matter in the direction of travel. Â*Now think deepely. Â*What
is a direction of travel without a rest frame? Â*What if the both the
rest frame and the object were biased to each other in direction of
travel to a third FOR that could name itself 'the rest frame'?
Hardly anyone considers this and only gets a superficial
understanding.

However. Â*In GR, there IS distance biased to the direction of gravity
that is measured by lightspeed. Â*It is confusing to all and is still
dominated by an infantile understanding of the physic. Â*Iow, we have a
skewed view of how this works, but readily apply a math to make it
apply for our purposes of measurement.

Quit grabbing formulas off the shelf only to satisfy a measurement and
find out the logic that must apply to provide such a physic.- Hide quoted text -

- Show quoted text -

Well, a third frame of reference is a good idea, but scientists will
not discuss a third frame of reference. Anyway, the mathematics is
probably too difficult for people who use the Lorentz equations for
all of their thinking. In any event, the distance contraction that
appears in the Lorentz equations is not an imagined factor. It is a
crushing of distances to satisfy a wrong equation.
Robert B. Winn