Science Forums 2

[martillo]

Trying to clarify the thing better I'copying here what I have posted in other forum:

I will copy here what I have posted at SCI Forums what I think clarifies the thing better:

The point is that a change in the reference frame (the observer) cannot alter the behavior of the system ot phenomenon being analyzed. In other words the reality of the system/phenomenon cannot be changed and that is what is happening in the presented problem. By reality I mean all the characteristics and properties of the system/phenomenon itself.
If you change the reference frame you would get different expressions for many things as velocity, acceleration, the Force, etc but for example, as in our case, the relatrive movement between the electron and the beam of must be the same, but if you observe carefully the relativistic transformation of the frames you will find that they determine two different movements, two different phenomenons. This cannot happen.

In other words, in the problem the relativistic prediction is the same as the classical prediction, fine, but the classical prediction is that the isolated electron will behave differently in the two presented cases of the problem. Now, Classical Physics determines two different behaviors because it considers that if a new absolute velocity is given to the isolated electron and the beam then this actually is a new phenomenon, a new system whith justified different behavior.
Now how Relativity consider and justify the two cases? The relative initial velocity of the two cases is the same so they would represent the same phenomenon, the same system for Relativity, then, how two different behaviors (to match with the classical prediction) are justified? Remember that just a change in the freference frame have been done. Then how?
I don't understand. I see a big problem here.