In my opinion, the difference lies in the fact that the spins of the quarks combine in such a way that in the case of protons and neutrons the total spin is 1/2, while in the case of the delta particles it is 3/2; this is a physically observable difference.
For what concerns the difference in...
Hi, in my opinion the computations you have proposed are right. It may be easier to write the exponential as cos+i sin and then use the formulae (from wikipedia :) to compute integrals like sin( ax) cos( bx) or sin( ax) sin( bx) .
Francesco
Yes: from the 4-th Maxwell's equation (ignoring the electric field: the problem is a magnetostatic problem):
\nabla \times \vec{B}=\frac{4\pi}{c}\vec{J}
Integrate over a surface S; transform the integral of the rotor in a line integral through one of the usual theorem (Green's theorem...
I don't know whether I have understood rhe problem, but I have worked out the situation in which the wire is on the same plane of the circle (in general I think that the computation is conceptually easy but hard in the practice).
In this case, the magnetic field generated by the wire at...
You are welcome; in any case, the correct statement is: let A and B be commuting operators with nondegenerate eigenvalues; then, if |a\rangle is an eigenstate of A, |a\rangle is also an eigenstate of B; moreover, if |a\rangle and |a'\rangle are two eigenstates of A corresponding to different...
Hi! In my opinion it is easier to proceed in the following way: consider the case in which A and B commute (the other case is analogous); in this case there exists a common set of eigenstates; this induce in the formula you want to prove a lot fo deltas (eigenstates corresponding to different...
Hello! I don't know whether I have understood what you have written; but in the case in which \langle \phi(x_1)\phi(x_2)\rangle = f(|x_1-x_2|) and the behavior you have written is not just a behavior but an equality, then in my opinion you can try the following mathematical trick: the equation...
Eh?I don't understand. Can you write an explicit formula for the phase space factor in which a linear combination of two particles with different masses is produced, please (and also the scattering cross section in terms of the invariant amplitude)? Or can you give a reference?
Moreover I think...
Thanks for your answer; I'm also sorry beacuse I have also edited a question which might have not seen: if a state which is not a mass eigenstate is "really" produced, how can you compute the cross section or the decay rate for such a process? Isn' there a mass parameter in the phase space? For...
Hello! I'm not a neutrino expertise, but I know the "usual" paradigm; (and indeed I made reference to it in this thread: https://www.physicsforums.com/showthread.php?t=591256, where I made also reference to an alternative possible interpretation); after all, neutrino osccillations are a...
This does not mean that T3 is the electric charge up to a constant (up to a constant means T3->k*T3, where k is a number); what you have written means that you are considering a U(1) factor under which the doublet is charged with charge 1/2 (the operation of you have called "up to a constant" is...
Q
T3 is not the electric charge up to a constant:
T_3|p>=\frac{1}{2}|p>
T_3|n>=-\frac{1}{2}|n>
(they are eigenstates of T3 just because we "label" our states with T3).
Moreover, what does the example you have given mean? That in processes mediated by QCD in the limit in which...
Dear Vanadium 50,
first, please, read what one asks; second, answer the questions posed without repeating ad libitum the same thing you have written in your first post; third, you should be more precise, in my opinion.Q is the charge of what symmetry? T3? The total isospin? T1? Something else...
You didn't answer my question: also T1 commutes with H (what is Q?), otherwise the hamiltonian would not be symmetric under the vector isospin symmetry. T3 or T1 are just ways to label the states, it does not have nothing to do with physics and to what nature should do.
So you are saying that...
Why T3 and not T1? Suppose what you have said is true: then I build a theory in which I label my states not with eigenstates of T3 but as eigenstates of T1; of course the two ways of labelling the "base vectors" are possible; there is also a relationship among the two set of states: in the case...