andrel <a_l### [at] hotmailcom> wrote:
> Also not sure what Mueen means, but the m in E=mc^2 is the m that was 
> used by einstein. IIRC the current definition would require a division 
> by sqrt(1-v^2/c^2). The old definition was certainly not quantified for 
> arbitrary velocities.

  I really can't understand what you are talking about. The 'm' which
Einstein used (and others before him) is what is currently used. There's
no "current definition of m".

  Don't confuse the 'm' in the E=mc^2 with 'm0' (m subscript zero), which
is the rest mass of an object. The 'm' in E=mc^2 is the relativistic mass,
and equal to m0/sqrt(1-v^2/c^2). That was the definition back then, and
that's the definition today. It hasn't changed.

-- 
                                                          - Warp

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