Re: Please explain where you get e=mc^2 from 1905 paper

On Sun, 14 Oct 2007 21:00:56 -0700, franklinhu@xxxxxxxxx wrote:

On Oct 14, 2:48 pm, Eric Gisse <jowr.pi.nos...@xxxxxxxxxxxxxxxx>
wrote:
On 14 Oct 2007 09:10:29 -0700, stevendaryl3...@xxxxxxxxx (Daryl

McCullough) wrote:
In article <lsi3h3de7sguvme3cq699kmdcvfcfdt...@xxxxxxx>, Eric Gisse says...

On Sat, 13 Oct 2007 22:47:44 -0700, frankli...@xxxxxxxxx wrote:
[...]

How do you get E=mc^2 from any of this?

You don't

Why do you say that? Einstein seems to derive E = mc^2 in the paper,
at least in the limited form, that if a massive object emits energy
E in the form of electromagnetic raditation, then its mass must
decrease by E/c^2.

I was using "you" in the sense of "you, specifically". That you get E
= mc^2 is rather straightforward to me because I'm capable of the few
lines of algebra needed. But he might appreciate the approach that
uses the invariance of the four-momentum scalar product.

Well, if you are capable of the few lines of algebra needed, then
indulge me and fill in the blanks between:

K0-K1 = 1/2(L/c^2)v^2

and

m = L/c^2

And if you could explain how he got to K0-K1 = 1/2(L/c^2)v^2, that
would be great too as there are a lot of lines missing to derive that
part as well.

thank you in advance.

Why not read the linked page?


I have already noted in my reply to Igor, that I am not interested in
methods of deriving E=mc^2 that cannot be directly tied to the 1905
paper. I'm interested in how Einstein derived the formula, not some
revisionist history version of it.

.

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