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Positrons are electrons travelling back in time by 
Ciro Santilli 35 Updated 2025-01-22 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-01-22 +Created 1970-01-01 Does the exact position of vertices matter in Feynman diagrams? by Ciro Santilli 35 Updated 2025-01-22 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-01-22 +Created 1970-01-01where:
- is the electromagnetic tensor
Note that this is the sum of the:Note that the relationship between and is not explicit. However, if we knew what type of particle we were talking about, e.g. electron, then the knowledge of psi would also give the charge distribution and therefore
- Dirac Lagrangian, which only describes the "inertia of bodies" part of the equation
- the electromagnetic interaction term , which describes term describes forces
As mentioned at the beginning of Quantum Field Theory lecture notes by David Tong (2007):
- by "Lagrangian" we mean Lagrangian density
- the generalized coordinates of the Lagrangian are fields
Anomalous magnetic dipole moment of the electron by Ciro Santilli 35 Updated 2025-01-22 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-01-22 +Created 1970-01-01Richard Feynman Quantum Electrodynamics Lecture at University of Auckland (1979) mentions it several times.
This was one of the first two great successes of quantum electrodynamics, the other one being the Lamb shift.
In youtu.be/UKbp85zpdcY?t=52 from freeman Dyson Web of Stories interview (1998) Dyson mentions that the original key experiment was from Kusch and Foley from Columbia University, and that in 1948, Julian Schwinger reached the correct value from his calculations.
Apparently first published at The Magnetic Moment of the Electron by Kusch and Foley (1948).
Bibliography:
- www.youtube.com/watch?v=Ix-3LQhElvU Anomalous Magnetic Moment Of The Electron | One Loop Quantum Correction | Quantum Electrodynamics by Dietterich Labs (2019)
Theorized for the graviton.
Leads to the Proca equation.
Photon hits excited electron, makes that electron go down, and generates a new identical photon in the process, with the exact same:This is the basis of lasers.
- frequency
- polarization
- direction
Bibliography:
Spontaneous emission defies causality by Ciro Santilli 35 Updated 2025-01-22 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-01-22 +Created 1970-01-01TODO understand better, mentioned e.g. at Subtle is the Lord by Abraham Pais (1982) page 20, and is something that Einstein worked on.
Deterministic, but non-local.
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