Assuming that c is a "conversion factor" to convert between space and time,(adsbygoogle = window.adsbygoogle || []).push({});

Then, in 4-vector, we have x_1 through x_3, and t, where, x/c = t

x/c = t, (where t = time, c= lightspeed, x = spacial dimension)

If we do what we did to space to get time, to momentum,

p/c = m*v/c = m (x/t) / c = m(x/c)/t = mt/t = m

we actually end up with mass... not energy...

So, there is an inconsistency, and I must have made a mistake somewhere. Can you please describe the method and mathematical proof and context for calling energy the component of momentum that is in the time dimension?

Thank you very much. -- j

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# In 4-momentum, why is E the 4th component?

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