Recent content by Anton Alice

One can distinguish between fast and slow decaying luminscence. The fastest kind of luminescence is fluorescence. There is also phosphorescence, which is more of an "exite, and wait until it decays", whereas fluorescence is more of a direct conversion of one wavelength to another...

I know its difficult. For the continuous approach: How well can optical filters block light? What is the best possible attenuation (below 200dollars)?

Hello forums, in the context of a little DIY-project I am planning to build a rudimentary fluorometer, which is actually doing nothing but checking whether an amount of protein is fluorescing or not, and roughly measuring its intensity. A highpower LED is used to excite the protein to the...

I am happy about every opportunity to get into the CogSci-Branch. My preference would be the Neural Network and Machine Learning part. What do we have in Physics, that ties on that? Complex dynamic Systems? Link between Quantum Information Processing and Information Processing with Neural...

Hello people, I am currently in my third year of Physics B.Sc., and I will prospectively get the B.Sc. Degree in half a year...if I just knew in which direction to go. I wonder if it I can get into cognitive science and machine learning from that position. Which physics bachelor theses do build...

I was also wondering if it is possible, to show

Ah ok. But just to be on the safe side, with "relativistic conservation of four momentum" you do NOT mean the lorentz-invariance, but the four-vectorial conservation in the case of interactions, right? I am just a little confused about the terminology.

If small type p is the kinetic momentum, what then is capital P?

So in the end, if I get it right, I am only interested in \vec p=conserved \Rightarrow E=conserved. And the proof of E=conserved \Rightarrow \vec p=conserved is not necessary, since I assume that \vec p=conserved is true under any circumstance.

If you want to modify the Hamiltonian by introducing the effect of an electromagnetic field, then the replacement \vec p \rightarrow \vec p - \frac{e}{c}\vec A is applied. Now my question is, whether there is a descriptive meaning of that extra term - \frac{e}{c}\vec A. As what can I think of...

In a relativistic treatment of mechanics one can say, that momentum and energy are correlatively conserved. The argument I would use, is that the length of the four-momentum is lorentz-invariant, and therefore, if E is conserved in any frame of reference, so the momentum. But I don't know, if...

Does that mean, that if I am very close to a radiative source (with close I mean a distance, which is much smaller than the wavelength of radiation), I don't experience radiation?

Thank you for your response. Could you elaborate on that a bit more? Because I can't see the reason, why I should neglect the displacement current, if there is a non-zero time derivative of E. The fact, that E changes in time does not depend on whether I look at a wavelength scale, or...

First of all, hello. I have a problem in understanding the skin effect. Often I read, that the skin effect is directly caused by eddy fields inside the conductor, which oppose the "desired" current flow. Problem at this is, that the eddy fields are not in phase with the desired current. The...

Yes, that imagination was rather utopic. I planned a trip to Switzerland, Berner Oberland (the Eiger is also in that region). For me as a student such a guided tour is not affordable. But I found another mountain (in that same region) which has a smaller (due to global warming), bypassable...