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As an occupation, I'm a mathematical physicist, studying string theory and quantum field theory.

I've developed as a hobby a few Cocoa (Touch) apps. The largest one so far is spires.app, which manages articles and metadata downloaded from the arXiv eprint server, the inspire database, and the journal websites.

I'm also interested in many other things, which is why I ask questions in various StackExchange sites ...


Jan
17
comment Construction of the supersymmetric Faraday tensor
@QuantumDot Read Wess-Bagger. The answer is there.
Nov
3
comment Is there a theorem that says that QFT reduces to QM in a suitable limit? A theorem similar to Ehrenfest's theorem?
@Prathyush Ask as a separate question. That's how stackexchange works.
Jul
16
comment About 2+1 dimensional superconformal algebra
Now that you understand that point, I think you should stop asking and think for several days by yourself. Good luck!
Jul
16
comment About 2+1 dimensional superconformal algebra
You need to distinguish two questions: what is the representation of the supercharge and what is the representation of the quantum states the supercharge is acting on. In order to get the inequality you're interested, you need to consider the latter question. You can't fix $I$ to be $N\times N$ and $M_{\mu\nu}$ to be $2\times 2$. They depend on $h$ and $j$. You try extracting $j$ from the $M_{\mu\nu}$ you already fixed, but that's not the point. $j$ depends on the quantum states.
Jul
14
comment About 2+1 dimensional superconformal algebra
2) Right. 3) The author didn't say Gamma are all real, he just said sigma is real. 4) You need to understand that the matrices M are determined by j and that the metrices $I$ are detemined by h.
Jul
14
comment About 2+1 dimensional superconformal algebra
1) The right matrices to use depend on the quantum states. What you wrote down is not OK even in a single superconformal multiplet. How did you determine which matrix representations of SO(N) and SO(2,1) to use?
Jan
2
comment General Relativity research and QFT in curved spacetime
@Kyle: That's also an interesting subject, but I meant this type of things: arxiv.org/abs/0905.4352
Dec
29
comment Wilson/Polyakov loops in Weinberg's QFT books
I don't know if it's in it or not (look for "area law" or "confinement" in it). Note that you and I may think this topic as classic, but I guess it can be too modern a topic for him. Anyway, just stop regarding his book as sacred.
Dec
16
comment On the Coulomb branch of N=2 supersymmetric gauge theory
Well, anything which was done in the last century should be considered basic. The SUSY textbook by Terning covers basic stuffs pretty well.
Dec
15
comment On the Coulomb branch of N=2 supersymmetric gauge theory
There's a reason why textbooks and papers are called differently:) I say, you should just try reading a paper which interests you most, using various references. If you can, then you're ready; if you can't, then you're not.
Dec
12
comment On the Coulomb branch of N=2 supersymmetric gauge theory
Once you finish a basic QFT textbook and a SUSY textbook, just pick whatever recent paper which motivates you most, and try to understand it. The required materials are either in the review sections or in the references in the paper. Going through it line-by-line won't work, because the author didn't intend the paper to be read that way. Rather, try to work out an example which is slightly different from what's dealt in the paper. That way, you'll learn exactly which tools are necessary, which part of the paper can be improved, and once done, it might result in your paper!
Dec
11
comment On the Coulomb branch of N=2 supersymmetric gauge theory
Which topic are you referring to? Chiral rings? This paper arxiv.org/abs/hep-th/0211170 contains a nice review. In general, read and understand all papers by Seiberg or by Witten. Problem solved.
Nov
19
comment “finite” QFTs and short-distance singularities and vanishing beta functions
@Anirbit , even in free field theory there's a loop integral which diverges: i.e. a one-loop diagram without any vertex. This corresponds to the zero-point energy of free oscillators, which makes the partition function diverge in the UV. So, your points 1,2,3 already apply to the theory of one free boson, and are always there.
Nov
18
comment “finite” QFTs and short-distance singularities and vanishing beta functions
Please rephrase your question. Even a theory of free bosons $\phi$ has a short distance singularity in its two-point function $\langle \phi(x)\phi(y)\rangle$.
Nov
3
comment How to prove quantum N=4 Super-Yang-Mills is superconformal?
Your argument is definitely nicer :)
Oct
28
comment Miura transform for W-algebras of exceptional type
By improving the program now the expression is about ~0.9MB :)
Oct
27
comment Miura transform for W-algebras of exceptional type
Thanks, I managed to get the generators. The degree-9 one was not so bad; but the degree-12 one, when dumped to a file, has ~ 100MB as an expression. Oh Buddha.
Oct
26
comment Miura transform for W-algebras of exceptional type
Thanks everyone; I know got the generators at degree 2 and 5. Now I need those at degree 6, 8, 9 and 12 :p
Oct
26
comment Miura transform for W-algebras of exceptional type
Yes you're right. Physicists cover their lack of deep thinking by lots of explicit calculation:p I've been using that approach to find generators of W(E6), but that's still quite messy. That's why I asked the question here.
Oct
26
comment Miura transform for W-algebras of exceptional type
Thank you, but my main problem is to explicitly write down the subalgebra commuting with the screening operators. For A and D, it's done by Fateev-Zamolodchikov and Fateev-Lukyanov. Their forms are quite useful because it can be readily implemented in a computer algebra system. I just want to perform a few stupid calculation inside W-algebra of type E6, but I first need to realize it inside computer.