Fermion Definition and 112 Threads

I'm still struggling to understand, that why precisely have I not understood what the Dirac's field is. hmhmh... okey, my question is this: Where does the anticommutation relation \{a_j,a_k^{\dagger}\}=\delta_{jk} come from? Is there something better than: "because the commutation relation...

Problem: How do you quantize a two dimensional system defined by the Lagrange's function L=\dot{x}y - x\dot{y} - x^2 - y^2 ? This is a non-trivial task, because the system has some pathology. Classically the equations of motion are \dot{x}(t) = y(t) \dot{y}(t) = -x(t), and for...

Homework Statement 1.Show that PV^Y is a constant for adiabatic,quassistatic expansion of a photongas and determine Y 2. Show the same for full degenerate gas of fermions at T=0 Homework Equations The Attempt at a Solution Plz help thx

Directly from the Peskin & Shroeder, page 63: S_F(x-y) = \int\frac{d^4p}{(2\pi)^4}\frac{i(\displaystyle{\not}p + m)}{p^2-m^2+i\epsilon} e^{-ip\cdot(x-y)} I'm slightly confused with the notation with the contractions. Things like \overline{\psi}(x)\psi(y) and \psi(x)\overline{\psi}(y) get...

four fermion interaction?? The four fermion interaction proposed by enrico fermi to learn weak interaction postulates that four dirac fields interact via the interaction hamilton J1^{}u*J2_{}u where J1^{}u=phi_d(x)*y^{}u*phi_c(x) but by question is this is the bilinear form taken...

Homework Statement Homework Equations Given is c_p = \sum_{n_i} (-1)^{N_p}|...,n_p=0,...><...,n_p=1,...| c_p^{\dagger} = \sum_{n_i} (-1)^{N_p}|...,n_p=1,...><...,n_p=0,...| N_p = \sum_{i=1}^{p-1}n_i Verify \{c_p,c_q\} = \{c_p^{\dagger},c_q\} = \{c_p^{\dagger},c_q^{\dagger}\} = 0...

Let me see if I get it right or I dreamed it: in order to give mass to a quark or a lepton the higgs field must be in the same isospin representation that the fermion, must it? IE, can a particle in a isospin triplet get mass from the minimal higgs? Or in the reverse, should a triplet higgs...

An elegant way of writing the standard model Lagrangian. The paper is titled "Standard Model Lagrangian" and is on this site: http://federation.g3z.com/Physics/ This appears to fit well with my preon model of the fermions; and helps fill in how one connects up the gauge bosons in that sort...

Is a baryonium baryon or meson? For example, deutorium, a n-p bound-state, has total spin 0 pr 1, so it is boson, then, it is meson? But it has baryon number (3+3)/3=2. For another example, bound-state of \Lambda_c - \bar{\Lambda_c}, has total spin 0 or 1, so again it is boson, it is meson...

Since we have anticommuting relations for the quantum Dirac fields, this will bring us to the similar classical correspondance but result in Grassmann spinor field function instead. (such as path integral) So when we consider an arbitrary interaction term that like (\bar{\psi} \psi)^n, if...

an atom consists of an electron (spin 1/2) and a positively charged spin 2 particle at the nucleus (in place of the proton). is this 'atom' a boson or a fermion?

One thing is bothering me from "the beginning". Let's take one fermion. It has spin, charge and mass (of course). This particle is surrounded with static magnetic field (becouse of it's spin), and with static electric field (becouse of it's charge). Both field (separately) are...