Recent content by durand

tstin, thanks a lot for your post, it helped a lot!

Yeah, I did find that, however, it uses a relativistic derivation so I can't really see how to do the last step as it's totally different to mine :/ Thanks anyway. My exam's in an hour so it doesn't really matter now. Thanks everyone for your help :)

Mmm, ok. I think I might be doing that next semester at uni.

CoM: h/λ = mv + h/λ' CoE: hc/λ = hc/λ' + 0.5mv² By substituting one into the other, I reach the formula I mentioned in my first post.

Uhm, I derived the first using conservation of momentum and energy at non relativistic speeds, when the photon bounces back. The second comes from the standard compton scattering formula.

Hi, I'm trying to derive a simple formula for 180° scattering. I've got to this stage and I really can't figure out how to simplify it further. \[ \frac{1}{\lambda}-\frac{1}{\lambda'} = \frac{2m_ec}{h} \] What I actually need is: \[ \lambda' - \lambda = \frac{2h}{m_ec} \] I'm...

Ok, I'l definitely keep that in mind! Thanks.

Thanks everyone! I didn't see that gamma could be taken out of the equation and cancelled. It works now :D

Ive tried the obvious replacing x and t with x' and t' but i still can't get it to drop out :(

How do you prove x2-c2t2 is invariant under the lorentz transformations given that;

Ok, that makes sense. Another simple question. Would a collapsing core become a neutron star first, or would it become a black hole in one fluid movement? Thanks for your help!

Oh, I read (on wikipedia and some books) that a shock wave causes the supernova, and that this shock wave is caused by the bounce back of matter. I guess you would get a lot of energy converted from gravitational potential as the core collapses?

Hi, I'm trying to understand how exactly a black hole fits into the evolution of red supergiants, especially in terms of a timeline. I understand that when the core of the star collapses, it reaches a point where the neutron pressure overcomes it's gravitational force and this deceleration...