- #1
ehrenfest
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Homework Statement
One thing that has been bothering me about the light-cone gauge that Zwiebach uses is that we have equations such as 9.63 and 9.71 in which X^+ and X^- are given by completely different expressions.
I am not sure why this makes sense physically since we can interchange X^+ and X^- just by moving to coordinate system in which X^1' = -X^1. So, shouldn't it be arbitrary which coordinate is X^+ and X^- and if it is arbitrary and coordinate-system dependent, how can physics depend on which way we choose our coordinate system?