Re: KuJomu - the writing

En réponse à Lars Henrik Mathiesen <thorinn@...>:

>
> That is indeed so in most modern formulations of the Special Theory of
> Relativity. But I'm pretty sure that back when the expression first
> got popularized, m was used for the 'relativistic mass', i.e.
>
>                         m = \gamma m_0
>
> where m_0 is the rest mass. With that definition, E = m c^2 is exactly
> correct.
>
Except that it's misleading, because most people don't know about the
difference between rest and relativistic mass and everyone who quotes this
takes the mass to be the rest mass. So it stays a misquote, even if in the
mouth of some people it may not be. I may be anal about all this, but to me a
good scientific quote must be unambiguous and unmisleading.

> (And to be even more modern, your E is the Minkowski norm of the
> energy-momentum four-vector, and in the particle view the energy
> component is again m c^2).
>
Only in the rest frame of the particle. Like I said, nearly nobody ever takes m
to be the relativistic mass. Even Einstein himself rarely used this convention.

Christophe.

http://rainbow.conlang.free.fr

Take your life as a movie: do not let anybody else play the leading role.

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