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When calculating density of states for an electron, some arrive that k (the wavenumber) is $2\pi n x /L $ and some say it is $\pi n x /L$?
Where L is the dimension of the well
I’ve heard vague explanations of “you’re using only one quadrant of k space” but I truly have no idea what they’re talking about.
What is the difference in these two results and why does it occur?