Question: Does Epsilon = i A^+/p^+ for Zwiebach Page 178?

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SUMMARY

The discussion centers on the interpretation of the gauge condition epsilon = i A^+/p^+ as presented in Zwiebach's text. The participant initially questions the validity of this expression, believing epsilon to be both infinitesimal and constant. However, it is clarified that Zwiebach refers to epsilon as an arbitrary function of the coordinates in Section 3.3, thus resolving the confusion regarding its nature.

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Homework Statement


Below equation 10.77, Zwiebach claims that the gauge epsilon = i A^+/p^+ makes the vector potential component A^+ vanish.

However, I thought epsilon was supposed to be infinitesimal and a constant, both of which are violated by setting epsilon equal to the expression?


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The Attempt at a Solution

 
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I thought epsilon was supposed to be infinitesimal and a constant, both of which are violated by setting epsilon equal to the expression?
Actually, just above equation (10.68) on page 177, he refers you back to Section 3.3 where on page 43, just below equation (3.19) he writes that epsilon is an arbitrary function of the coordinates.
 
I see. Thanks.
 

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