Notes

Hi there! Welcome to my notes page!

Here I will share most of my course notes from my master’s studies at EPFL. I also plan to post notes on a variety of topics in Theoretical Physics and Mathematics. I firmly believe that the best way to truly understand something is to write it down independently, so I aim to create a learning note for topic I think extremely interesting. Of course, mistakes and disorganization are inevitable, but I hope that these notes can still be helpful to others who are interested in the same topics.I plan to post all notes in English in the future, although some earlier notes are written in Chinese (apologies for that).

The source code of all notes are hosted on my GitHub repository. Btw the template for the notes are also open sourced here for latex notes and here for typst notes

Table of Contents

• Lecture Notes
• Learning Notes

Lecture Notes

Here are the lecture notes I took during my master’s studies at EPFL.

• Quantum Field Theory 1 (in Chinese)
• Quantum Field Theory 2
• General Relativity and Cosmology 1 (in Chinese)
• General Relativity and Cosmology 2
• Quantum Mechanics 3 (in Chinese)
• Quantum Mechanics 4
• Quantum Information Theory (in Chinese)

Learning Notes

These are the learning notes I compiled while exploring a range of topics in theoretical physics and mathematics.

Here are my notes in Condensed Matter Physics (CMT):

• Quantum Hall Effect This is a note on the quantum Hall effect, covering both the integer and fractional quantum Hall effects.

  Here are my notes on Quantum Field Theory (QFT):

Here are my notes on 2-Dimensional Conformal Field Theory (2D CFT):

• Basic 2D CFT This is a concise note on 2D Conformal Field Theory (CFT), covering the basics and some key results. The idea flow is originally from the yellow book. In fact personally I don’t think this is a very good way of understanding 2D CFT, but it is a good starting point for beginners. Once one have a basic feeling for CFT, I’d prefer turn to the Boostrapping construction of CFT, which is more systematic.
• Basic BCFT This is my study note on Boundary Conformal Field Theory (BCFT). It mainly focus on the boundary state formalism. If I have time its also possible to include some topics on gluing conditions and calculation of boundary and bulk OPEs.
• Conformal Blocks Crossing Thi is a note on one of the most important feature of 2D CFT, the crossing symmetry of conformal blocks.

Here are my notes on 2+1 Dimensional Quantum Gravity :

• 2+1 Dimensional Gravity and Chern-Simons Theory This is a note on 2+1 dimensional gravity and its relation to Chern-Simons theory. And a naive approach on real polarization quantization method in the zero cosmological constant case.