Quantum numbers and Differential Equations

I wanted to write up an introductory description of the Standard Model of particle physics, but the project has gotten out of hand as I want to start from first principles and I forget that from there, the trail is long.

Feynman Diagrams for the Masses (part 2)

In part 1, we briefly discussed how Feynman diagrams show up in QFT with an example taken from QED (quantum electrodynamics). The calculation for the first order correction to the photon propagator (i.e. vacuum polarization) turned out to be a rather messy integral:

QFT’s little Infinity Problem
This is a mess because it (a) involves the trace [...]

Feynman Diagrams for the Masses (part 1)

If you want to win a Nobel Prize in Physics by finding the unified field theory, it’s pretty obvious that you will have to learn how to make Quantum field theory (QFT) calculations. In the 1940s, Richard Feynman and Ernest Stueckelberg independently developed a notation (now known as Feynman Diagrams), that greatly ease certain calculations [...]

The Bilson-Thompson Helon (Braid) Model

In 2005, Sundance O. Bilson-Thompson wrote hep-ph/0503213v2, an arXiv paper titled “A topological model of composite preons”. The paper gave a preon model of quarks, leptons, and gauge bosons. That is, it modeled these particles as composite particles made up of preons. The preons he used were elements of the braid group B_3. A later [...]

Measuring the Speed of Gravity (Waves)

Newton’s equations give the speed of gravity as infinite. For example, in Cartesian coordinates, suppose a gravitating mass 2M is at the origin up until time t=0.  At that time, the mass splits into two masses of mass M, one going in the +x direction at speed v the other in the -x direction at [...]