A simple algorithm for automatic Feynman diagram generation

TL;DR

This paper introduces a straightforward algorithm for automatically generating Feynman diagrams from their fundamental definitions, simplifying the process for researchers in theoretical physics and field theory.

Contribution

It presents a simple, easily implementable algorithm that directly derives Feynman diagrams and their symmetry factors from the definition formula, along with a versatile C-program implementation.

Findings

The algorithm naturally generates symmetry factors for each diagram.

The C-program is short, fast, and supports arbitrary models and processes.

It facilitates new calculation techniques and tools in effective field theory.

Abstract

An algorithm for the automatic Feynman diagram (FD) generation is presented in this paper. The algorithm starts directly from the definition formula of FD, and is simple in concept and easy for coding. The symmetry factor for each FD is naturally generated. It is expected to bring convenience for the researchers who are studying new calculation techniques or making new calculation tools and for the researchers who are studying effective field theory. A C-program made from the algorithm is also presented, which is short, fast, yet very general purpose: it receives arbitrary user defined model and arbitrary process as input and generates FD's at any order.