"Dirk Van de moortel" wrote
in message ...

"snapdragon31" wrote in message
...

[snip]

Yes, there are tons of solutions to the twin paradox but none of them
is a valid solution.
Let me show you why it is a logical problem that has no solution.
Assuming that Lorentz transformation can predict the time and distance
of the other frame.
Let v = velocity of the moving twin M
x = distance measured by stationary twin S
t = time measured by twin S
x' = distance measured by twin M
t' = time measured by twin M

The information we have is:
1. v - velocity of moving twin.
2. x = v * t

This equation is valid for events satisfying
x' = 0,
expressing the fact that is the velocity of the origin of
the primed system is v w.r.t. the unprimed system

No .. x = vt is valid for all times t. It is the position of object M as
measured from S at time t

3. x' = v * t'
Expressing the (erroneous) fact that is the velocity of
the origin of the unprimed system is *also* v w.r.t.
the primed system. That is wrong. The velocity is -v
This is your first error.

Yes .. as I think I noted, he got some signs wrong .. not a fatal error
though in this case .. we can pretend he is talking about speeds

4. x' = x * sqrt(1 - v^2/c^2)
Only valid for events satifying
t' = 0
Exercise: Why?

No .. it is valid for all times t .. at time t, S sees M at x=vt, then at
the corresponding time t' for M, M sees S at x' = -x * sqrt(1 - v^2/c^2)

5. t' = t * sqrt(1 - v^2/c^2)
Only valid for events satisfying
x' = 0
Exercise: Why?


No .. by the same logic as above

So if you combine equations 4 and 5, you are talking about
events that satisfy
x' = 0
t' = 0
and therefore also
x = 0
t = 0
Exercise: Why?

No .. it is not