Recent content by Ancient_Nomad

Hi everyone, I know that there is a result that corresponding to a closed p-form α, I can find a p-1 form β, such that dβ = α. I wanted to ask, what the tensorial analog of this would be. I mean would it be right to say that on a manifold with a lorentzian metric, If I have a vector...

I am sorry. I should have specified that I was talking about the electron not bound states like proton or neutron. But yes, in principle we should try to extend any answer we get (if we do) to them. That is true. I guess my question can be rephrased as 'why should the magnetic form factor is...

Hello Everyone, In a course on field theory I was asked to calculate the first order correction for Lande g factor. I noticed that this comes out to be positive. ie g-2 > 0 I am wondering if there is a physical reason why this must be positive. Or is it just a matter of chance, that this...

Hello, How is a static magnetic or electric field understood in terms of QED. Is it correct to interpret them as a collection of photons? If so, would these photons be real or virtual? Thanks in advance.

What are Hard QCD processes ?

Can you please explain what will happen to the electrons (and to fermions in general) on rotation by 2*pi. What do you mean by, "they won't return".

Hello, I was studying about the effect of a beam splitter in a text on quantum optics. I understand that if a and b represent the mode operators for the two beams incident on the splitter, then the operator for one of the outgoing beams is the following, c = \frac{(a + ib)}{\sqrt{2}}...

Well, if |i> and |j> form a complete set of basis vectors (and i believe they do in this case), then the above expression reduces to this, E<i|h|j>[<r|i><a|j> - <r|j><a|i>] = <r|h|a> - <a|h|r> = 2*iota*Im( <r|h|a> ) where Im() represents the imaginary part.

Hi, I think you are a little confused. The N in J_z represents the Number Operator which is defined as a^dagger*a Where as the N in the square root is just a number and is equal to the eigen value of the Number operator. Conventionally, that's what I would think of, when I see the...

EDIT: sorry for that earlier post Let p > q. Now, if q does not divide p-1 then any group of order p*q must be cyclic. (This is a result which can be proved easily with sylow's theorems) A simple example are groups of order 15 = 5*3. If on the other hand, q does divide p-1 then this group...

Hello, I was thinking about how to predict the order of an element a*b if the orders of a and b are known where a and b are elements of some group. One textbook I have gives the result (without proof) that if a and b commute and their orders are relatively prime, then order(a*b) =...

Hi, My mathematics professor said that it is possible to construct a Laurent series of sqrt(z) about zero by integrating over a keyhole contour and then taking the limit R --> 0 where R radius of the inner circle. But I think he is mistaken. I don't understand how it is possible to have a...

Thanks for the reply. I worked it out using the way you suggested. It comes out correctly and easily. But I would still like to find a way using contour integration. For those who are interested, the answer is \frac{ln(2)}{2} . Edit: The given integral can be found by solving the...

Hi, Can someone tell me how to integrate functions which have a branch point and a pole (of order > 1) on the x-axis. Specifically, I ran into the following problem while playing around with contour integrals, which has a double pole at x = -2 . I tried to do this with a keyhole contour...