Recent content by lanbeiming

i still have a question, if we put a generater and detecter on both sides of a, say cubic-like, material, with size say,a*a*a, then the time we measured from the generator to the detecter would really be different from a/Co ?

thanks, but if you don't mind, could you tell me how the velocity of intersection points are related to the phase velocity?

thanks for reply, but i don't understand this: v_g/c = (Compton wavelength of particle)/(deBroglie wavelength of particle) and the reciprocal of this is equal to v_p/c. how could the left-hand-side ratio and right-hand-side ratio(p/mc) be linked? could you show me the duduction or some...

jsut one more question, can you show me the meaning of shutter-down？i'm not sure so see that the pulses can't be used to send messages faster than light in vacuum. thanks!

Nice applet!:smile:

understanding for group velocity and phase velocity?? Hi, everyone. I learned physics for 3 years, but up to now I still cannot understand clearly the difference between the group & phase velocity. What is exatly "phase"? and what is exactly "group". From book I read the Vph corresponds to the...

1.hi, everyone. here's the question :BF3 is a planar four-atomic molecule. For simplicity, we ignore the degrees of freedom in the z-axis (principal axis). a) Find the reducible representation for a base consisting of the 8 unit vectors with origin at each atom, being parallel to the x and y...