String theory for the curious / 数理物理学 (2026)

Overview

I revived the slot with the title Mathematical Physics / 数理物理学 in the Graudate School of Physics in 2024, and use it to give a lecture on basic algebraic topology aimed for theoretical physicists for two years. This year I'm going to discuss string theory instead.

This will be a course to introduce string theory for those who do not intend to become string theorists themselves but are curious about what string theory actually tells us at the graduate school level. For example, you might have heard that string theory is a prime candidate for quantum gravity and that string theory has been a source of new mathematics.

What do these statements actually mean? I intend to answer these and other questions you might have in the lectures, not just at the level of books for the general public, but hopefully in a way convincing to those who already understand physics at the undergraduate and the basic graduate level. I would welcome the participants to pre-submit the questions from this web form so that I can prepare better in advance.

Misc info

• I am going to assume basic knowledge of quantum field theory and general relativity, as covered by the standard courses provided by our department of physics. I am not going to assume that you have mastered these subjects.
• I'm going to prepare lecture notes myself, without any specific textbooks to be used.
• The lectures will be recorded and will be made available to the member of the university.
• Please also see the course page provided by the university.

Plan of the lectures

Lecture 1: What do you want to know about string theory?

After giving a general overview of the course, we'd like to have an open question session, to assess what the audience members want to know about string theory. Honest and direct questions will be appreciated, and you can pre-submit the questions from the web form. I will not be able to answer all the questions on the spot, but will try to answer them over the course of the lectures.

Lecture 2 & 3: What is so hard about quantum gravity?

I would like to review which theoretical aspects of quantum gravity are harder than quantum versions of other parts of the real world.

Lecture 4 and onward:

The content will be chosen depending on the questions I received during the lecture 1.

To get credits

I'm going to post a list of suggested problems for you to work on. To get credits, please pick at least one, and submit it via UTOL.

The histogram of the submission times relative to the deadline in the lectures I did in the past can be found here: Record of submission times. It's interesting to see that people always submit very close to the deadline!

Date and time

Autumn semester, 2nd slot of Thursdays, from 10:25 to 12:10.

email: yuji.tachikawa_at_ipmu.jp