Re: Relativity

[Benn Tannenbaum <bennt@ATTBI.COM>]

Remember that relativity is relative! From the
electron's perspective, it's not moving, but the
positron is. The best thing to do is to consider the
motion of the center of mass of the system-- in that
frame both are moving with the same speed.

In my mind, though, there's something else that's
more important: the concept of relativistic mass. I
think it's a terrible idea. Mass is a function of the
number of protons, neutrons and electrons in an
object, plus the mass of the energy that binds them
all together. Does that really change depending on
your reference frame? I don't think so. Instead of
talking about relativistic mass, talk about relativistic
momentum. It makes far more sense to me, and
then the student's question is rather moot.

--
Benn Tannenbaum
Post Doc, Department of Physics & Astronomy
UCLA
> I am way over my head with this one but I wonder if someone can help.
>
> If a stationary positron (in some frame of reference) is struck by an
> electron moving relativisticly, is there perfect conversion of the mass
> into energy considering that, from the point of view of the positron,
> the electron has more mass than the positron.
>
> A high school student asked this and I have no idea what to tell him.
>
> Thanks for any suggestions.
>
>     David Abineri
>
>
>
>
> --
> David Abineri
> dabineri@choice.net