Building a Solid knowledge of Quantum Field Theory

[Silviu]

Hello! I read several books and took courses on quantum mechanics and particle physics and I understood the topics. However I feel that I have only pieces of informations without a global image of what is going on. For example in the particle physics classes we were given Feynman rules without too many details on how to obtain them and we just applied them. I would like something that would help me feel the gap between quantum mechanics and particle physics (with all the main derivation presented), basically I want to really understand how to use quantum mechanics in particle physics. Can you recommend me some (as complete as possible) resources for this? Thank you!

 

[eys_physics]

I recommend the book "Quantum Field Theory and the Standard Model" by Schwartz. It is a very comprehensive book with many details.

 

[Arifi]

I recommend "Student Friendly Quantum Field Theory" By Robert D Klauber. It is relatively easy to follow.

 

[Demystifier]

Another vote for Klauber!

 

[Silviu]

Another vote for Klauber!

Thank you for advice. About the book, how complete is it, as usually when they have "Student" in their name the books are a bit dumbed down, and some parts are missing. Also, do you think it can be found online for free?

 

[Dr Transport]

Klauber or QFT for the gifted amateur

 

[Demystifier]

About the book, how complete is it, as usually when they have "Student" in their name the books are a bit dumbed down, and some parts are missing.

It contains the basic stuff, not the advanced, but the derivations are presented in fair details. From your first post, it looks as if this is what you need. The book by Schwartz recommended above is more advanced and complete, but I wouldn't recommend it for the first book on QFT.

Also, do you think it can be found online for free?

Yes, but not legally.

 

[Demystifier]

Klauber or QFT for the gifted amateur

QFT for the gifted amateur is great, but it's not ideal for those who know from the start that they want to specialize in particle physics.

 

[vanhees71]

I'm still puzzled by Klauber's book. What's "student friendly"? I find it quite confusing. E.g., where is a clear derivation of the LSZ reduction formalism which is crucial to understand the S matrix? I'd still recommend Schwartz's book as the first book for QFT.

 

[Demystifier]

E.g., where is a clear derivation of the LSZ reduction formalism which is crucial to understand the S matrix?

I think LSZ is not essential to understand S-matrix, especially if mathematical rigor is not the goal.

 

[smodak]

Hello! I read several books and took courses on quantum mechanics and particle physics and I understood the topics. However I feel that I have only pieces of informations without a global image of what is going on. For example in the particle physics classes we were given Feynman rules without too many details on how to obtain them and we just applied them. I would like something that would help me feel the gap between quantum mechanics and particle physics (with all the main derivation presented), basically I want to really understand how to use quantum mechanics in particle physics. Can you recommend me some (as complete as possible) resources for this? Thank you!

Quantum Field Theory by Padmanabhan
https://www.amazon.com/gp/product/3319281712/?tag=pfamazon01-20

Quantum Field Theory I & II by Manoukian
1. https://www.amazon.com/gp/product/3319309382/?tag=pfamazon01-20
2. https://www.amazon.com/gp/product/331933851X/?tag=pfamazon01-20

 

[Arifi]

I'm still puzzled by Klauber's book. What's "student friendly"? I find it quite confusing. E.g., where is a clear derivation of the LSZ reduction formalism which is crucial to understand the S matrix? I'd still recommend Schwartz's book as the first book for QFT.

Actually, we don't have to use LSZ reduction formalism to calculate S matrix.
But, anyway, I also recommend Schwartz for QFT book.

 

[vanhees71]

I think LSZ is not essential to understand S-matrix, especially if mathematical rigor is not the goal.

LSZ is the key to understand the meaning of QFT in the first place, and it's a difficult concept. For get mathematical rigor. It's well known that so far there is no mathematically rigorous definition of interacting quantum fields for realistic (i.e., Standard Model) cases :-(.

 

[vanhees71]

Actually, we don't have to use LSZ reduction formalism to calculate S matrix.
But, anyway, I also recommend Schwartz for QFT book.

How else do you want to calculate the S matrix?

 

[Demystifier]

LSZ is the key to understand the meaning of QFT in the first place

The purpose of science is not to give a meaning, it's to make the measurable predictions, right? I can calculate S-matrix, and hence make measurable predictions, without using LSZ.

Of course, LSZ is needed if I want to calculate S-matrix from n-point functions. But I don't need to calculate S-matrix from n-point functions. For instance, the old-fashioned Dyson approach does not rest on n-point functions.

 

[Arifi]

The purpose of science is not to give a meaning, it's to make the measurable predictions, right? I can calculate S-matrix, and hence make measurable predictions, without using LSZ.

Of course, LSZ is needed if I want to calculate S-matrix from n-point functions. But I don't need to calculate S-matrix from n-point functions. For instance, the old-fashioned Dyson approach does not rest on n-point functions.

I do agree with you. This is what I mean.

 

[Demystifier]

E.g., where is a clear derivation of the LSZ reduction formalism which is crucial to understand the S matrix? I'd still recommend Schwartz's book as the first book for QFT.

Even your favored advanced QFT textbook, namely Weinberg 1, explains S-matrix without LSZ. It mentions LSZ only much later, in Sec. 10 Non-perturbative methods (Sec. 10.3 to be more precise).

 

[vanhees71]

Ok, in this sense, you are right. Perhaps I should have a closer look at Klauber's book, before I comment on it. So far, I've glanced over it and decided to use other books ;-)).

 

[Demystifier]

Ok, in this sense, you are right. Perhaps I should have a closer look at Klauber's book, before I comment on it. So far, I've glanced over it and decided to use other books ;-)).

Well, Klauber is much more pedestrian than Schwartz, which might be the reason that you, as an expert in QFT, prefer Schwartz over Klauber. But I think students usually like pedestrian approaches.

 

[vanhees71]

Pedestrian is never wrong, but it should be a nice walk rather than one with a lot of pitfalls ;-).

 

[MinasKar]

I recommend David Tong's lecture notes http://www.damtp.cam.ac.uk/user/tong/qft.html
It is pretty easy to follow.

 

[Joker93]

Quantum Field Theory by Padmanabhan
https://www.amazon.com/gp/product/3319281712/?tag=pfamazon01-20

Quantum Field Theory I & II by Manoukian
1. https://www.amazon.com/gp/product/3319309382/?tag=pfamazon01-20
2. https://www.amazon.com/gp/product/331933851X/?tag=pfamazon01-20

What is each textbook's level(compared to e.g. Peskin's)?