We propose a two-component form to describe massive relativistic fermions in gauge theories. Relations between the Green＇s functions in this form and those in the conventional four-component form are derived. It is s...We propose a two-component form to describe massive relativistic fermions in gauge theories. Relations between the Green＇s functions in this form and those in the conventional four-component form are derived. It is shown that the S-matrix elements in both forms are exactly the same. The description of the fermion in the new form simplifies significantly the γ-matrix algebra in the four-component form. In particular, in perturbative calculations the propagator of the fermion is a scalar function. As examples, we use this form to reproduce the relativistic spectrum of hydrodron atom, the S-matrix of e＋e-→μ＋μ- and QED one-loop vacuum polarization of photon.展开更多
基金Supported by National Natural Science Foundation of China under Grant No. 10475103
文摘We propose a two-component form to describe massive relativistic fermions in gauge theories. Relations between the Green＇s functions in this form and those in the conventional four-component form are derived. It is shown that the S-matrix elements in both forms are exactly the same. The description of the fermion in the new form simplifies significantly the γ-matrix algebra in the four-component form. In particular, in perturbative calculations the propagator of the fermion is a scalar function. As examples, we use this form to reproduce the relativistic spectrum of hydrodron atom, the S-matrix of e＋e-→μ＋μ- and QED one-loop vacuum polarization of photon.
