Recent content by A_s_a_d

I agree, Sakurai's text is for grad studies.

It would be very much helpful. :)

If it has no physical reality, would you please explain how Casimir force originates between two plates in an empty vacuum?

I enjoyed Garry Bowman's 'Essential quantum mechanics' for developing intuition. QM by Shakurai is my favorite which is mathematically rigorous, also helps to develop intuition.

Thanks, modified the Hamiltonian in the question .

In the discussion of calculating specific heat for a solid, it is assumed that the whole solid body is a molecule with N atoms and the Hamiltonian of this solid is similar to that of a molecule with N atoms, i.e. ## \mathcal{H}_1=\mathcal{V}^{*}+\sum_{j=1}^{3n}...

Yes, it's the same sum but scaled. One thing I have found that if you approximate the summation as integral, it can be proved easily as both are usual Gaussian Integral. But I was worrying about the factor that involves to transform the summation into integral. Any thoughts?

I found the following identity in a paper: ## \sum_{l=1}^{\infty}exp(-\pi\alpha l^2)=(\frac{1}{2\sqrt{\alpha}}-\frac{1}{2})+\frac{1}{\sqrt{\alpha}}\sum_{l=1}^{\infty}exp(\frac{-\pi l^2}{\alpha}) ## Someone please let me give some hints on how to prove this.