Recent content by liumylife

Solution I found the solution in Griffiths' book: Chap.10, (10.31), generalization of the Biot-Savart law.

Homework Statement There's a infinitely-long straight line in vacuum goes through space, carrying a current which is time-dependent. What is the magnetic field induced by the curent? B, vector, the magnetic field E, vector, the electric field J, vector, the current density ρ, scalar, the...

Wow, that's cool, you know this year is a "snake year" in Chinese tradition. I'd known someone from UCB who come to China to seek opportunity to start his own business, and I found him really understand many things about Chinese and our life, like TV shows, Chinese-made movies, pop songs...

HaHa, that's right. No one actually say it but kids, I can remember I used to say it when I was a kid, before or after I got the red envelope, both ways are ok since people who give kids envelopes must be family members. Funny thing to say is I had to prepare many different words other than...

Thank you all for your wishes~

Wow, you can really make others see Chinese here, how nice. Chinese is somehow difficult for first-timer to learn and speak, as my USA friend told me, and I think Chinese culture is really broad and deep, so worth understanding.

Cool, I heard the ball-dropping is an very old tradition for NY people.

Do you guys know that today(2/10) is the first day in Chinese calendar? so happy new year guys. By the way, is there any Chinese here?

This seems a better path, I'll try, thank you.

Thank you for reply. By the way, how do you make the integral sign so large? Latex? I had tried to type in the Latex code but it didn't work.

Homework Statement I need to give scattering amplitude f(θ) in Born approximation to the first order in the case of delta function scattering potential δ(r). The problem is in spherical coordinate and I'll give major equation concerned.Homework Equations The equation for scattering amplitude is...

OK, since the quasiparticle behaves like monopole, dose it produce magnetic field? Does moving "spin ice" produce EMR?

I know Dirac had said yes to existence of microscopic monopole by quantum theory, so why not the macroscopic monopole?

I saw your point. Thank you, everyone.

Right, that is much clearer. Thanks.