# (ALPHA) String Theory Course/Discussion

#### BenTheMan

##### Dr. of Physics, Prof. of Love
Valued Senior Member
Ok, first. This is an alpha thread, and will be monitored very closely for trolling. All commentary in this thread should directly pertain to the subject at hand.

Secondly, this thread is not intented for everybody, as I hope the discussion will be at a somewhat advanced level. We can start another introductory string theory thread if you'd like.

Either way, if this thread dies, it dies

I am taking a course on string theory this Winter at OSU, taught by Prof. Samir Mathur. The lecture notes will be online. If anyone is interested in following along with me, please let me know. I don't know that anyone will be willing to follow along, but if you are, please post in this thread.

Nice! I want to give a shot, even though I might not be prepared enough.

Yeah, I'll give that a shot too. I may know nothing about the math, but I can learn that right?

I would love to learn and discuss string theory. I am as we speak reading a book on it.

Cool!

Ok. The first set of lecture notes is available at the aforementioned website. I'd suggest downloading them and reading them. I'll try to supplement the notes with some comments here and there.

The class is 10:30-12:18 on MW. If you guys have any questions that I can't anwer, I will ask Samir.

Yeah, I'll give that a shot too. I may know nothing about the math, but I can learn that right?
If you don't know much about Lagrangians, equations of motion, Noether's theorem, group theory, QM, relativity, complex analysis and field theory you're going to struggle. A lot. They are all taken as base knowledge for any string theory course because string theory uses them all. There's a reason string theory is a 4th year or postgrad course in universities, it needs so much background knowledge.
If anyone is interested in following along with me, please let me know. I don't know that anyone will be willing to follow along, but if you are, please post in this thread.
I'd like to do it. I've sat a string theory course before but didn't do that well in it and it didn't cover branes or much about gauge fields (ie Chan-Paton). I could do with a brush up.

/edit

By the way, do you have a link to the question sheets for this course or hasn't he put them up yet?

AN---

Samir hasn't set any hw assignments yet, but I'll let you know if he does. He also typically sets an end of term assignment, like a paper or something.

The reccomended textbook is Becker Becker and Schwarz, but I have talked to him and he told me it really isn't necessary to buy.

Also, all of the lectures are being recorded and archived. I'll post links to them when I get more information.

Also, I have a set of string nots that notes that I am working on. They follow mostly GSW, but the notes are very detailed. There are several typos that I KNOW about, so I am a bit hesitant to put them on the web so everybody can see what an idiot I am

lanl.arxiv.org/abs/hep-th/0207142

These notesare pretty good. I've got lecture notes by Michael Green but they aren't LaTeX'd and I missed one of the lectures in the middle

Here's some question sheets from that course :

damtp.cam.ac.uk/user/examples/3P6a.pdf
damtp.cam.ac.uk/user/examples/3P6b.pdf
damtp.cam.ac.uk/user/examples/3P6c.pdf

They can provide some topics for discussion too. I'll have a pop at a few of the first sheet's questions later today. I have to work on a poster for our department's poster day. Somewhat of a waste of time but at least I get to use a picture of a Calabi Yau space to make it look snazzy.

/edit

I've had to remove the ww w. from the links since the forum won't let me post links for another 16 posts...

Hi Ben,

I just got the M theory by Schwarz book out from our library (despite the library having had it for a number of years, I'm the first one to get it out...) and it's excellent. It is certainly more readable than Polchinski, who feels a bit like the Weinberg of string theory. Weinberg's textbooks on QFT are excellent, if you already know a fair amount of QFT. Not for beginners though. I like how Schwarz et al. give solutions to their homework problems too. The fact they answer them immediately under the question does make it a little tempting to just read the answer though!

AN---

Thanks for the heads up on Becker, Becker, and Schwarz.

Samir's second set of lecture notes are up, about solving string equations of motion. Most of the stuff through the first couple of lectures has been review of the classical problem, so I am hopeful of things picking up soon.

If anyone is following along and has questions, it would be great if we could discuss them, or I can pose them to Dr. Mathur.

You learn something new every day.

The world sheet coordinates, $$\sigma, \tau$$ are dimensionless. In hindsight this should be obvious, as sigma is an angular variable ($$\sigma \in [0,2\pi]$$, but sometimes I'm a bit dense.

I'll try to keep this thread bumped by giving a short synopsis of things that weren't in the class notes after every lecture.

I've never seen the explaination that he provides for the energy of the zero modes of the string. I've seen that you can consider contour integrals and thus end up taking the residue of $$\zeta(-1)$$, that's how Polchinski does it, but I've never seen it explained as the difference between the continuous and discrete systems. That certainly gives a much nicer physical explaination of why it's finite.

That certainly gives a much nicer physical explaination of why it's finite.

Yeah... Samir is FULL of these kinds of explanations.

Ok, I'm digging this thread up from the past to hopefully resurrect some interest. I will try to post an update at least once a week (hopefully twice a week) about the topics that Samir covers each day.

The webpage is still up, and Prof. Mathur has added several sets of notes, if anyone is still interested.

Why not simply start from the introductory level?

Absolutely interested. I've been going through Zwiebach's book and would love to have some other material to help solidify things in my mind. Much anticipated Ben.