Editor's Notes

1. Most complex thing I ever learnt. Explain in 7 minutes?Talk features complicateddiagrams and photos of dead physicists
2. Light = electromagnetic spectrumWave-like nature: oscillating electric and magnetic fieldSpeed, frequency, wavelength
3. ‘GCSE view’ of light and matterElectrons as hard particles orbiting a central nucleus
4. Discovered by Heinrich Hertz, 1887Red light won’t cause emission of an electron, blue light will
5. Electron diffraction: wave-particle dualityDiscovered 1929 George Paget ThomsonClinton DavissonLester Germer
6. Erwin Schrödinger, 1926the E=mc2 of chemistryTime-dependent version shown
7. Solutions to the wave equation show that electron trajectories are not sphericalArranged in ‘shells’ spdDonut shape
8. Electronic energy states are quantisedAbsorption and emission spectra (colour)Einstein predicted lasers (stimulated emission)
9. Some things are fundamentally unknowable
10. Thought experiment50:50 chance exists as both alive and dead until it is observed
11. Now we deal with systems in terms of probabilityProbability amplitude: diffraction if two slits, not if one (or a detector at one)Thomas Young (probably), 1803
12. Classic view of light wavefront slowing (army marching through swamp)QED view of light taking every single available route, but probability reinforcing
13. Personal heroDouble Nobel laureateSafe cracking at Los AlamosChallenger disasterBongo playerAmazing humility(auto)biographies
14. Time, space axisWiggly = photonStraight = electron or other massive particle
15. First Feynman diagram 1949Photon travels back in time!
16. Matter and antimatter
17. One of the things QED allows us to calculatePredicted value adjusted by correction terms
18. Despite the strangeness of ideas above, it provides the most remarkable agreement between theory and measurementDifference equivalent to thickness of human hair when measuring the distance from East to West Coast USA
19. Also: Lamb shift, Compton scattering, etc.