Perturbative quantum field theory (Q2746656)

The author treats QED and QCD with the Hamiltonian \(H=H^{(0)}+ gV_1+g^2V_2\) as Perturbative Quantum Field Theory. The eigenstates \(|m_n \rangle\) of \(H^{(0)}\) are free electrons and photons in QED, and free quarks and gluons in QCD. Each term in \(V=gV_1+g^2V_2\) defines a process that mixes free states. He solves the Schrödinger equation \(i\hbar\partial_t |\psi(t) \rangle =(H^{(0)}+ V)|\psi (t)\rangle\) with boundary condition \(|\psi(-\infty) \rangle= |m_0\rangle\), and obtains the formulae of \(\langle m_n |\psi(t) \rangle\) and \(\lim_{t\to \infty}\langle m|\psi(t) \rangle= \Gamma(p)\).NEWLINENEWLINENEWLINENext he shows various experiments as ``favorite tests'' under the agreement with Brookhaven National Laboratory. Reaction \(e^++e^-\to Z+H\) by the LEP II at CERN is contained in the tests. Finally he explains \(Z\)-decay \(\Gamma_z\) given from ``\(\Gamma_z^{(EW)}\) with no QCD-interactions'', jet cross-section \(\sigma_{2J}\), and the factorization formula for the hadronic part \(W_N (q,p)\) of the cross-section \(\sigma_{eN}=L_e (k,k')\times W_N(q,p)\) associated to the deep-inelastic scattering \(e(k)+ N(p)\to e(k')+ X(p+q)\).