Recent content by Viona

That was helpful. Thanks. I learned that this type of integrals are called iterated integrals. For this type of integral the order is important particularly when the integrand is not continuous on the domain of integration. Then I found a theorem called Fubini’s Theorem. I understood that we...

Yes. it seems good. But I want to ask: for this type of integral does the order matter? I should start by integrating w.r.t. r2 first or it is optional?

I want to do this integral in the picture: where r1 and a are constants. I know I can integrate each part separately. There will be an integral with respect to r2 multiplied by integral with respect to theta2 and the last one with respect to phi2. But the term under square root confuses me. Can...

Sorry, the electron's orbital momentum points in the same direction of the magnetic field. Thanks!

Yes the period the same. But The direction of the angular momentum is parallel to the direction of the magnetic field, then the electron orbital momentum vector should point to the opposite direction?

I though the periodic time and the radius of the rotation are affected by the relativistic motion, so the periodic time from the point view of the electron will be different from the point view of the proton.

I was reading about Compton scattering. I have a question I did not find an answer for it in the book (Concepts of Modern Physics-Sixth Edition-Arthur Beiser) or in the internet search. My question is: Is the incident X-ray beam, with the original wavelength, detected at different scattering...

I was reading about characteristic x rays. I have a question I did not find an answer for it in the book (Concepts of Modern Physics-Sixth Edition-Arthur Beiser) or in the internet search. My question is: How do the atom in the target (in the x ray production experiment) go to the normal state...

I tried but the results did not convince me!

why smaller cross-sectional area increases the resistance of a conductor?

TL;DR Summary: Gerald Burns's book: Solid State Physics: is it good for begginers or there are best books? Hello, I am looking for the best book to study solid state physics for begginers. Some one recommended Gerald Burns's book: Solid State Physics. So, what is your opinions about this book...

He said he is going to use a process of successive approximations, I am not familiar with the "asymptotic expansion" so I can not tell if this what he did

In equation [9.15] ##c_a(0) = 1## this is before the perturbation (at time ##t= 0##) no transition happened yet and the particle still in the upper state ##a##. But equation [9.17] after perturbation at time t and ca(1)(t) = 1 is the first-order correction. I understand that the zeroth-order...

He used a process of successive approximations, so for this two particle system the particle starts at state ##a##, then at time t=0: ca(0)=1 and cb(0)=0. If there were no perturbation the system will stay there forever, so we can say the zeroth- order terms are: ca(t)=1 and cb(t)=0. To...

I was reading in the Book: Introduction to Quantum Mechanics by David J. Griffiths. In chapter Time-Dependent Perturbation Theory, Section 9.12. I could not understand that why he put the first order correction ca(1)(t)=1 while it equals a constant.