Is velocity a more accurate measure of energy in Einstein's equation?

AI Thread Summary
The discussion centers on the interpretation of velocity in Einstein's energy equation, E=mc². It questions whether velocity, which has direction, should be replaced by speed, a scalar, to accurately represent energy. The argument suggests that using speed would eliminate the directional aspect of velocity, aligning better with the concept of energy. The mathematical representation of velocity squared as a dot product is also mentioned, reinforcing the idea that the result should be a scalar. The conversation ultimately explores the implications of these definitions on understanding energy in the context of relativity.
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This is an interesting point that I just thought of while listening to one of Einstein's own lectures on his theory of relativity. In it he said that energy is equal to mass times the velocity of light squared.

But doesn't velocity have direction? And wouldn't this imply energy has direction? Obviously it doesn't. Speed, on the other had, is a scalar, so I would think it would be mass times the speed of light squared.

What's your opinion?
 
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Velocity of light squared would be
<br /> \vec{v}^2 = \vec{v} \cdot \vec{v}<br />
The dot product makes the final result a scalar rather then a vector
 

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