A quote from an old thread reads "Energy is the time component of the momentum 4-vector"(adsbygoogle = window.adsbygoogle || []).push({});

That quote came from a Science Advisor.

Does this mean that time can be either a) substituted for energy in the momentum 4-vector, or b) seen as equivalent to energy in the momentum 4-vector? Hmm, maybe my a) and b) are the same. Regardless, the question remains. If the answer is "No," then is there a physics 4-vector that includes time? I say "physics" as to discern them from purely mathematical 4-vectors.

Also, when working with physics 4-vectors of the same sort, such as comparing physics 4-vectors of the same sort, do all the constituent vectors combine of a given physics 4-vector? If so, what are the operators of how they combine?

Thanks,

Jake

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# Time in Physics 4-Vectors

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