Recent content by r4nd0m

yeah, I have been doing it informally, i.e. nothing will show up on my transcript.

The need of having done a class "formally" I'm (something like) a master student in Europe, now being in my first year and I have the following problem: Last semester I was attending lectures on QFT, but I haven't done the exam/assignments, since it was way too much for me that semester and...

We have been discussing this topic with my classmates recently, and I find it quite interesting, so I also want to ask you guys: 1. For how long can you study without taking a break? 2. How long are your breaks? 3. What do you do in the breaks?

If you're interested in hep-th, then you might consider: Cambridge, Oxford, Imperial College London, ETH Zurich, LMU Munich, University Utrecht. They all have very good reputation in hep-th and I think that all of them offer master's degrees in theoretical physics. As to what your chances are...

I'm interested in doing my PhD in theoretical and mathematical physics - i.e. subjects like Quantum Field Theory, String Theory or Quantum Information Theory. My question is which universities in the US have really good programs in these areas?

It depends on whether you want to do theory or experiment. If it's theory, then theoretical/mathematical physics would be the right field, with taking some additional math and computer science courses, like Functional analysis, Advanced Algorithms, Complexity theory, Coding Theory,... In...

Aah, I see, the problem with my formula was that if I changed f, x_i would change too. Your picture, jtbell, explains it very well. Thank you very much for your time.

This is perfectly clear. This is the critical point. Let's say that the heigth of the object is y_0, the focal length is f, and the distance from the focal point to the film is x_i (as in the first picture in http://www.inyourfacefotos.com/fstop.htm). Then by similarity of triangles the...

ooops, you're right of course, N is the inverse of the f-number. Anyway, I still seem to misunderstand something. I found this 'derivation' of the equation, here: http://www.inyourfacefotos.com/fstop.htm , although I quite don't understand some of the steps there (even if it's elementary...

Well, it's actually in most of the books on photography, but it's never derived. They say, that when you change the aperture by a factor of sqrt(2), the intensity of light will change by factor 2.

I've been searching through the internet and some of my optics books, but nowhere was I able to find the derivation of the law for a camera lens, that the intensity of light that comes on the film or chip is proportional to \frac{D^2}{f^2}=N^2, where D is the aperture diameter, f the focal...

Has anyone done this? I'm a physics major and I'd like to pursue a degree in mathematical physics. I guess that physics GRE is expected from me as a physics student, although actually I feel much more comfortable in math. Do you think that it would be hard to make both? Would it make me...

Lie group = group + differentiable manifold, hence knowledge in both algebra and differential geometry is needed.

Traditonally, it is about solving mathematical problems that arise in physics (and are too difficult to be left to the physicist :-) ) - like finding a solution to some PDE, making integral transforms, minimizing some functional,... But it can also mean mathematically rigorous study of...

The answer is definitely Differential Geometry, especially when you want to do QFT, where it is widely used. It will also give you much insight in other subjects (apart from the obvious GR), like classical mechanics, electrodynamics, advanced QM,... it's everywhere. Real analysis might be also...