Thanks for your replies! I am just trying to follow the working in an old thesis. I am expecting a single index result in the form of a force so I think their use of the term tensor product was in fact a little misleading.
Thanks again, this has been very helpful!
Hi all, I'm pretty rusty on my index gymnastics, I'm wondering if someone can explain to me the correct way to take the tensor product of a general 4-vector ## g^{\mu} ## and a tensor ## P^{/mu\ /nu} ## in Minkowski space. The part that is troubling me is the fact that both have a ## \mu ## as...
I think the title of your thread "Do we really need the Hilbert space for QM?" was a reasonable question and this was the question I chose to answer in my response. Indeed I think you were advised of a number of other approaches to QM that may be the answer you were looking for. I'm not entirely...
I'm in total agreement with VanHees and others on this.
One alternative approach that can be taken in QM (and many other areas of physics) is to formulate quantum mechanics in terms of the spacetime algebra (STA). The STA is a real geometric algebra, in this approach one does away with complex...
Hi folks,
Hope everyone is keeping well. I've recently read the headlines of "strong evidence for new force of nature" pertaining to the Muon g-2 experiment. Interesting as I find the article in the BBC linked below:
https://www.bbc.co.uk/news/56643677
I'd love to read some...
I believe the edges use representations of su(2) to encode curvature, the representations are the holonomy of the connection, this provides the link from curvature on a Riemmanian manifold to the discretized space of LQG. If we take a number of infinitesimal rotations in the form of su(2)...
They would if they were traveling through the same magnet, but they are not. As is shown in the picture handily posted by @ChrisVer, the counter propagating beams are traveling in separate beam pipes, with separate magnets.
At the LHC the counter propagating beams are transported in separate beam pipes before their paths are overlapped using magnets to cause particle collisions.
Coherent beam combination is very much an active field of research. The idea is to take several laser beams and combine them such that there phase relationship is locked and one gets constructive interference of the EM wave. This is difficult and requires phase modulation at sub-femtosecond...
I'm unaware of any books specifically dedicated to Feynman diagrams, but an entry level QFT text should have a lot of what you are looking for. I found Peskin Schroeder (An Introduction to Quantum Field Theory) very useful when studying for my masters, and still lean on it on the occasion I need...
In the field of classical optics the description of light as an electromagnetic wave is central, and hence its electric and magnetic components are very important. As an example many optical instruments are sensitive to the waves polarization state, which tells you the transverse behaviour of...
The Coulomb force law needs to be modified such that ##R_n## takes into account the true separation of charges. The separation in the compactified extra dimension is given by this ##4\pi n R## term which is specific to the Torus geometry. If the extra dimension was compactified on a circle you...
Many thanks for your contributions, I understand the issue much better now.
In fact I am currently reading about computational models for radiation reaction and the comparisons between classical, semi-classical and QED models. I've found this article, which may even be the one you mentioned...
Many thanks for your reply, this certainly addresses my confusion. If the mass ##m## is finite and then since ##\delta m## is divergent can we then infer that ##m_0## is also divergent? if so what is the source of this divergence?
Thanks for your help, I will certainly turn my attention to the...