I have provided some very simple arguments here
that clearly indicate a specific problem in
relativity. It is very straight forward and
fundamental, but it requires an equally straight
forward and fundamental solution. 100 years have
passed and nobody has solved it. Perhaps someone
here might do so.
First, concerning some basic requirements of
special relativity. Mathematically, it is defined
by the Lorentz Transformations:


where

(x is position, t is time, c is the speed of light
and v is the relative velocity)
Note that the Lorentz Transformations are based
solely on relative velocity. This is very
important, because there is nothing mathematically
wrong with the equations, but as a physics formula,
each variable relates to something physical and
therefore has physical implications built into
the equation. The implications here are that
two observers using this equation can say nothing
about their intrinsic motion. All the equation tells
them is how they are moving relative to each other.
Note also that these equations are very limited (and
not very practical) since they apply only in the
case of constant relative velocity. But no worry,
we can derive a differential form and get:

We do not even have to do any work since one can
simply copy it out of a text book (I used Jackson).
Now this formula turns out to be very practical
and is commonly used to determined the life-times
of particles moving at high velocities. Note that
this equation incorporates acceleration. It is
important to understand to which acceleration it
refers. The acceleration here, since it directly
correlates to the relative velocity of the
Lorentz Transformations is a relative acceleration.
That is, it is the change in relative velocity
over time. It is a purely kinematic value. It
tells us nothing about what forces are present.
It tells us only that the relative velocity
between the two observers is changing.
So far I have made no argument against relativity
and have only spoken of relativity exactly by
the book. So, if you have found yourself disagreeing
with anything mentioned so far, then you do not
understand relativity... so you can stop reading.
Now lets consider a specific physical situation.
I am not claiming any contradictions, but will
only set up the situation and see how the above
equations can be used in relation to it. (e.g. Be
used completely, be used in part, or used in a
modified form.)
Now imagine that there are two observers, observer
A watches observer B accelerate straight away from
him to a certain distance and then return to him
by the same route. Observer A uses equation (3) to
determine the time that has passed for observer B
relative to his own time and he finds that less
time has passed for observer B....exactly as
the equation has predicted.
Now observer B sees observer A kinematically
accelerate away from him and return in exactly
the same fashion as observer A had seen him do.
Observer B uses the same equation (3) giving the
same velocity and change in velocity to observer
A. His result is that less time has passed for
observer A relative to his own time. (This by
definition is a physical contradiction.) But it
turns out in reality that equation (3) gave him
the wrong result! observer A had in fact
experienced more time.
As everyone knows by now, observer B apparently
had experienced a force which caused his acceleration
(which was observed by A) and it caused B to see
observer A accelerate (change his relative velocity)
in relation to him.
Now was it wrong for observer B to try and use
equation (3)? It turns out that observer B had,
in fact felt the force that accelerated him, but
since there was still the same relative acceleration
created and since there was no term or factor
in the equation (3) indicating a force, there was no
reason to assume that he would get a wrong answer.
In fact, it was not the wrong choice by observer B,
it was the inaccuracy of the formula when being
applied by an observer being accelerated.
So far then there is not necessarily a contradiction
(since special relativity is a limited theory). What
we have learned is that the equations of special
relativity are wrong when being applied by an
observer who is accelerating (they still work if
only the observed object is accelerating).
Thus special relativity causes a contradiction
which is only resolved by special relativity's
failure to be accurate when used by an accelerating
observer.
Now since special relativity involves only relative
velocity and relative acceleration (change in relative
velocity) there is no possible way it can resolve
the contradiction, since it contains no reference
to the dynamic state of the observers. Thus it cannot
distinguish which actually accelerated. Of course,
the observers would know, but since the equations
do not contain the information, they are wrong when
applied in this case.
Thus if someone says that the reason there is no
contradiction is because one of the observers is
accelerating, he may possibly be right. BUT if
he claims that special relativity can give the
correct times for both observers and thereby
resolve the contradiction (right after he stated
that special relativity is invalid for one
of the observers) then he is hopelessly insane.
If you are one of these people, you can stop
reading now.
For relativity to survive, it thus requires that
general relativity supply an answer. What exactly
do we need from general relativity for this problem?
Equation (3) needs to be adjusted so that it has
terms or factors relating to the forces on each
observer in such a way that the formula gives the
correct time as observed by each, not just observer A
(the non-accelerating observer). When the force is
zero, then it should reduce to equation (3), but
only for the non-accelerating observers. Thus
in this example observer A, having experienced zero
force, would be able to use equation (3), but observer
B would use a modified version of equation (3)
which included factors or terms based on the force
he has experienced. This equation, on integration,
would then yield the correct passage of time of
observer A as seen by observer B.
General Relativity would have to be able
to provide the necessary corrections.
Until such corrections have been provided (not just
claimed).....Relativity remains self-contradicting.