Recent content by zalook

1. Radius of curvature of planetary motion

Suppose we have a planet of mass m orbiting a larger one of mass M along an elliptical path. If we use polar coordinates with the origin placed on the planet of mass M (focus of the ellipse) then at the instant when the smaller planet is at the point of closest approach we have: \boldsymbol{v}...
2. Bosons's amplitude to go into the same state at low temperatures

Since the context could be useful, it's in page 21-8 of the third volume.
3. Bosons's amplitude to go into the same state at low temperatures

Hi I was reading Feynman's third book and I don't understand why, with bosons at low temperatures, 'there's more amplitude to go into the same state than into an unoccupied state by the famous factor √n, where n is the occupancy of the lowest state'. Thanks.
4. Engineering Deciding between Mechanical and Electrical engineering

Thanks for the answers. I've already decided about getting an engineering degree, but my problem is that I can't decide between Mechanical and Electrical engineering. I'm not from USA, in my country in order to get an engineering degree you must spend five years at the university, so the times...
5. Engineering Deciding between Mechanical and Electrical engineering

Hello, I'm majoring in physics at the end of the year but I'm more interested in engineering now. The thing is that I could start taking Mechanical engineering classes now and obtaining the degree in two years from now (without obtaining the major in physics), or I could finish the physics major...
6. Expansion of a wave fuction in energy eigenfunctions

I know that, but I'm not sure if what I have said (barrier or well, it doesn't matter) is ok. I only want someone to confirm that. Thanks.
7. Expansion of a wave fuction in energy eigenfunctions

Ok, thanks. I understand what you are saying but in all the cases I have seen scattering treated they took only ONE incident particle, so they obtain superposition only in its side of the barrier (for example). My question is how should I take incident particle/s to get the eigenfunctions?. I...
8. Expansion of a wave fuction in energy eigenfunctions

Thanks, but I don't know if I understood that. I think you say that when writing a specific eigenfunction you must solve the well with coming waves from infinity and -infinity at the same time, is that ok?.
9. Expansion of a wave fuction in energy eigenfunctions

Ok, I get it now but I have another question: when you write the unbounded eigenfunctions how should I obtain them? I mean, how should i consider incident particles?. Thanks.
10. Expansion of a wave fuction in energy eigenfunctions

Hi, suppose we have an unidimensional finite square well potential and we want to expand an arbitrary wave function in terms of energy eigenfunctions but considering the possibility of bounded (discrete) AND unbounded (continue) states. How do you express the expansion?. The problem is that each...
11. Geometry book

Well, the kind of geometry showed in the book I mentioned: Euclidian mainly. By the way, have you used those books? Could you tell me your experience with them?. Thanks.
12. Geometry book

Hello, I am searching for a geometry book, a rigorous one. I have taken a look at Moise's and Downs's book but it looked too short, I want something more advanced but keeping the focus on elemtary issues at the same time. Thanks.