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9

I'm a bit rusty on my qed, but I'll give this a shot. The simplest case would be described by a diagram similar to: But the $e^--e^--\nu_e$ vertex doesn't exist (also note that I can't draw the required arrow on the neutrino) - the vertices of the standard model (with the exception of vertices involving the Higgs and neutrino oscillations) are: With ...


7

The magnetic moment of the electron is a magnetic moment, so the right magnetic field around it is $$ \mathbf{B}({\mathbf{r}})=\nabla\times{\mathbf{A}}=\frac{\mu_{0}}{4\pi}\left(\frac{3\mathbf{r}(\mathbf{\mu}\cdot\mathbf{r})}{r^{5}}-\frac{{\mathbf{\mu}}}{r^{3}}\right). $$ The world is quantum mechanical – and so is any viable description of the spin – so we ...


4

There are, in general, no closed form solutions (aka formulas) for the spectra of multi-electron atoms. There are reasonably precise formulas for special cases, like approximate values of x-ray transitions from inner shell electrons, though. Unlike in case of hydrogen and Rydberg atoms, which can be treated as a non-relativistic one-body problems (i.e. for ...


3

You should not imagine a virtual photon as an individual object wandering from one charged particle to another. This picture is simply inapplicable. Unfortunately, Feynman diagrams mislead people to imagine such things. Actually, Feynman diagrams are good for calculation and bad for imagination. Feynman diagrams have been introduced to help physicists to ...


3

There exists an extensive literature for discretization of the abelian and the non-abelian gauge theories, known as lattice QED and lattice QCD, respectively. Here we will only sketch the main idea. Let us for simplicity use Euclidean signature $(+,+,+,+)$. A small Wilson-loop $$\tag{1} W~=~{\rm Tr}{\cal P}e^{ig\int_{\gamma}A}$$ lies approximately in a ...


1

You can say that QCD is the opposite of QED. I don't know how much you know of Renormalization group, but QCD has an asymptotic freedom, that mean that when you go to higher energies, you can use perturbative theory to do cross section calculation. That because the coupling constant is running with energy, due to the Beta-function. The goodness of your ...


1

Your "question" contained way too much babble, so I'm only going to answer generally. You claim to understand Maxwell's equations, so you should be able to see how a inductor works for yourself. When a current flows thru a wire, a magnetic field is created circling around that wire. By wrapping the wire into a coil, the contributions from all the ...


1

All charged particles emit photons which are uncharged. They may, given the right boundary conditions. So how does the photon "know" that it's leaving one kind of charge and "lands" on another? What you are describing here is a "virtual photon", an interaction between two charged particles. There is the complicated way, i.e. mathematical ...



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