Equation 14.81 in Zwiebach: Why No 2?

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Homework Statement


In equation 14.81, why are the lower indices of the oscillators alpha^r and alpha^s not divided by 2 like they were in equation 14.77?


Homework Equations





The Attempt at a Solution

 
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ehrenfest said:

Homework Statement


In equation 14.81, why are the lower indices of the oscillators alpha^r and alpha^s not divided by 2 like they were in equation 14.77?


Homework Equations





The Attempt at a Solution


In my edition, equation 14.81 has no alpha (it has integrals with exponentials) . But my equation 14.82 has the commutator of alpha^r and alpha^s and they have, respectively, the subscripts m/2 and n/2.
I am not sure if you have that.
 
I'm sorry. I meant 14.80. Mine has subscripts of m and n (not divided by 2) so it must be a typo. That would make much more sense since the commutator of 14.82 in my book does have subscripts that are divided by 2.
 
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I'm pretty sure it's a typo. Here is Professor Zwiebach's errata page. It has his e-mail address where you can send him this one.

http://xserver.lns.mit.edu/~zwiebach/firstcourse.html"
 
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