FEYNMAN DIAGRAMS VIA GRAPHICAL CALCULUS

Feynman Diagrams via Graphical Calculus

It has been known for a while, in Hopf algebraists’ folklore, that there is a very close connection between the graphical formalism for ribbon categories and Feynman diagrams. Although this correspondence is frequently implied, it seems to have been first explicitly described in the recent [1]. Yet, we know of no systematic exposition in existing literature; the aim of this paper is to provide ...

Feynman Diagrams and the Quantum Stochastic Calculus

We present quantum stochastic calculus in terms of diagrams taking weights in the algebra of observables of some quantum system. In particular, we note the absence of non-time-consecutive Goldstone diagrams. We review recent results in Markovian limits in these terms. AMS Classification: 81S25, 81T18

JaxoDraw: A graphical user interface for drawing Feynman diagrams

JaxoDraw is a Feynman graph plotting tool written in Java. It has a complete graphical user interface that allows all actions to be carried out via mouse click-and-drag operations in a WYSIWYG fashion. Graphs may be exported to postscript/EPS format and can be saved in XML files to be used in later sessions. One of the main features of JaxoDraw is the possibility to produce L A T E X code that ...

Feynman diagrams versus Fermi-gas Feynman emulator

superstring Feynman diagrams

The multi-loop amplitudes for the closed, oriented superstring are represented by finite dimensional integrals of explicit functions calculated through the super-Schottky group parameters and interaction vertex coordinates on the supermanifold. The integration region is proposed to be consistent with the group of the local symmetries of the amplitude and with the unitarity equations. It is show...