Quantum Field Theory 4a - Second Quantization I

Previously we've seen how to quantize the electromagnetic field. This led us to define operators that create and destroy photons. We want to develop similar operators for electrons. The way we do this is the technique of "second quantization." Photons are bosons, which are not governed by the Pauli exclusion principle. Electrons, however, are fermions, which must satisfy the exclusion principle. Therefore, electron creation and destruction operators cannot be the same operators we used for photons.

This video borrows from Chapter 4 of A Pedestrian Approach to Quantum Field Theory by Edward G. Harris (ISBN-13: 978-0486780221).

[Cosmalano]

I just rewatched the series and wasn’t expecting another installment for a few months! Christmas came early!

[mikip]

Please, please. Never stop doing these videos. These are treasures for any student.

[Tim-Kaa]

This is gold. Please don't stop doing these vids.

[mehdisi]

I've been waiting for this series of your videos for a long time. Great, I hope you can complete this series of videos because they are so fascinating and popular. thank you very much

[arsenzatikyan]

Thank you very much for your scientific lessons. It is really deep learning. Тhanks for taking the time to record these valuable content!!!

[Cosmalano]

Don’t keep us waiting too long for that next episode! Great video

[hawzhinblanca]

Great video thanks, can’t wait for part b

[AbuSayed-ervs]

Amazing video series about a very complex idea QFT.And Above all Thanks a lot for your all video series which are extraordinarily simple and more visually appreciative to me.
Plz make some videos about classical physics like phace space, canonical transformation, Hamilton Jacobi equation and it's relation to Schrodinger equation etc.
Thanks again!

[briacroa]

The part that is obscure is this.
when field y(x, t) are superposition of b+ and b-, then which is the representation for b+ and b- ?

[Richardj]

Didn't expect this surprise. Thanks

[mehdisi]

Hi to you. I would like to ask what study resources can you offer me to study the QFT topic? Please list the best study sources you know in this subject. thank you very much.

[anthonysegers]

Watch in conjunction with reading Lancaster and Blundell 1st ed 2014

[nellvincervantes]

H = sum_k E_k*N_k ? So how could we get H = (1/2)hf for zero point energy?

[benjaminkaufmann]

I find the way you explain the "quantum jump" misleading. Every quantum mechanical system (even in quantum field theory) is described by continuous equations, and so every quantum system changes continuously. In other words, the transition from one electron state to another occurs through a continuous change in the wave function. The wave function never changes abruptly, as indicated in the video. Only the macroscopic measurement result seems to have this jumpy behavior. This means that if we ask the quantum system what state it is in, we will get a "discrete answer" - this state or that state. The wave function, however, changes continuously.
Edit: And also in QFT, the creation of a photon is a continous process! (Only the macroscopic oberservation shows "jumpy nature".)

[hafizajiaziz]

So, are we getting closer to renormalisation?