(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

I am somewhat confused about why Zwiebach sets up this space as a box with side lengths L1,L2,...,Ld and then requires that

[tex] p_i L_i = 2 \pi n_i [/tex]

i = 1,2,3,...d

Can somewhat explains what this equation means physically? Why would you multiply momentum by a length? If anything I would think you would divide momentum by a length to get the mass times the time?

And how can we imagine space as a box when I am assuming we are talking about the space in which we live which is infinite in each direction?

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Zwiebach page 172

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