Aspectos básicos del método de amplitudes I: caso sin masa

Authors

  • Jonathan Reyes Pérez BUAP

DOI:

https://doi.org/10.31349/RevMexFisE.22.010203

Keywords:

Amplitudes, little group, helicity, Weyl spinors

Abstract

En este trabajo se revisa el formalismo de los espinores de helicidad o el método de amplitudes en el espacio de cuatro dimensiones (D=4), en el contexto de la Electrodinámica Cuántica (QED, por sus siglas en inglés). Se muestran los cálculos explícitos de la amplitud del proceso físico e+ e- ---> mu+ mu a nivel árbol como un ejemplo de motivación a este método en el límite de altas energías o ultra-relativista. El objetivo es introducir a estudiantes de física en las nuevas técnicas de cálculo que se desarrollan a partir del formalismo de amplitudes.

In this work, the helicity spinors formalism or just amplitudes is reviewed in four-dimensional space (D = 4), in the context of Quantum Electrodynamics (QED). Explicit calculations for the amplitude of the physical process e +e − → µ +µ − at the tree level in the high energy or ultra-relativistic limit are shown as an example of motivation for study this method. The objective is to introduce particle physics students to the new calculation techniques that are developed from the amplitude program.

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Published

2025-01-01

How to Cite

[1]
J. Reyes Pérez, “Aspectos básicos del método de amplitudes I: caso sin masa”, Rev. Mex. Fis. E, vol. 22, no. 1 Jan-Jun, pp. 010203 1–, Jan. 2025.