1. Chapter 7

2. Equations

3. Warning! “What I am going to tell you is what we teach our physics students in the third or fourth year of graduate school - and you think I am going to explain it to you so you can understand it? No, your not going to be able to understand it….you see my physics students don’t understand it either, that’s because I don’t understand it. Nobody does.” Richard P. Feynman - QED

4. Feynman Lectures  http://vega.org.uk/video/subseries/8

5. If its so difficult why do we use it?

6. I would again like to impress you with the vast range of phenomena that the theory of quantum electrodynamics describes; It’s easier to say it backwards: the theory describes all the phenomena of the physical world except the gravitational effect,..,and radioactive phenomena, which involves nuclei shifting in their energy levels. So if we leave out gravity and radioactivity (more properly, nuclear physics), what have we got left? Gasoline burning in automobiles, foams and bubbles, the hardness of salt or copper, the stiffness of steel. In fact, biologists are trying to interpret as much as they can about life in terms of chemistry, and as I already explained, the theory behind chemistry is quantum electrodynamics.’ “Richard P. Feynman - QED”

7. Q.E.D  The most accurate scientific theory ever developed  For example it predicts the value of a particular constant to be Predicted value1.00115965221±4 Measured value1.00115965265±20  This is the same as measuring the distance from London to New York with an error equal to the thickness of human hair

14.  I am describing to you how nature works you won’t understand why nature works that way. But you see nobody understands that  “Richard P. Feynman QED”