Rotation of Feynman Diagrams around an Electron-Photon Vertex

​
rotation angle
-135°
-90°
-45°
0°
45°
90°
135°
180°
An electron exchanges a virtual photon in electromagnetic interaction with another charged particle.
Feynman diagrams are symbolic representations for interactions among elementary particles. An interaction occurs when particle trajectories intersect at a vertex. The fundamental vertex in quantum electrodynamics involves a photon γ, represented by a wavy line, and two electrons e, entering and exiting the vertex, represented by solid lines. Arrows oriented in the positive-time direction identify the particles as negatively charged electrons
-
e
. Arrows oriented in the negative-time directions represent antiparticles, positrons
+
e
propagating forward in time. Each Feynman diagram can be interpreted as an integral which contributes to the quantum-mechanical amplitude of a process, via a set of Feynman rules. Remarkably, different orientations of a Feynman diagram can represent alternative sequences of spacetime events. You can rotate an
eeγ
vertex into eight different orientations, each describing a completely different physical process. Included are electron-positron creations and annihilations, which contain the essence of Einstein's mass-energy relation
E=m
2
c
.

External Links

Feynman Diagram (ScienceWorld)
Quantum Electrodynamics (ScienceWorld)

Permanent Citation

S. M. Blinder
​
​"Rotation of Feynman Diagrams around an Electron-Photon Vertex"​
​http://demonstrations.wolfram.com/RotationOfFeynmanDiagramsAroundAnElectronPhotonVertex/​
​Wolfram Demonstrations Project​
​Published: November 5, 2007