- 47

- 0

I am just learning QED and could not understand the role of wave function. Is the basic equation in QED the

I have tried to read the original paper of Tomonaga in 1946

What I am confused about is the role of wave function in QED. In QM, the wave function means the distribution probability in the space (Born)? Then what concept or quantity in QFT means such things (distribution probability in the space) or corresponds to the wave function ? Is there some correspondence principle between QM and QED? Could the basic QED equation retreat to QM

For example, in the calculation of Lamb thift, what is the use of wave function (1s state of hydrogen)? It seems the Lamb shift has some connections with the wave function value at the r=0 point. Look at Baranger, Bethe, and Feynman's calculation. (Phys. Rev., Vol. 92, NO. 2,482) They use the wave function

Quantum River

**Schrodinger Equation**? Is the difference between Quantum mechanics and QED just they have different Hamiltonians.I have tried to read the original paper of Tomonaga in 1946

*Progress of Theoretical Physics*, but just not could get the original paper. I have no access to*Progress of Theoretical Physics*. And this is the only paper that concerns the foundations of QED in my knowledge. Dyson's review*The Radiation of Tomonaga, Schwinger, and Feynman*gives a rather short description of*Outline of the Theoretical Foundations*(Dyson's words). Could anyone recommend me some papers in this direction.What I am confused about is the role of wave function in QED. In QM, the wave function means the distribution probability in the space (Born)? Then what concept or quantity in QFT means such things (distribution probability in the space) or corresponds to the wave function ? Is there some correspondence principle between QM and QED? Could the basic QED equation retreat to QM

**Schrodinger equation**or**Dirac equation**under some conditions?For example, in the calculation of Lamb thift, what is the use of wave function (1s state of hydrogen)? It seems the Lamb shift has some connections with the wave function value at the r=0 point. Look at Baranger, Bethe, and Feynman's calculation. (Phys. Rev., Vol. 92, NO. 2,482) They use the wave function

**phi(r=0)**to calculate the Lamb shift. But there is no wave function (of course no 1s wave function) in Quantum field theory? When calculating scattering, it is easier to understand the role of QFT, but when considering the Bounded states, I just could not understand how to calculate the bounded state wave function from QFT.Quantum River

Last edited: