## Teaching

This page collects materials related to my teaching on various occasions, loosely in anti-chronological order.

**Selected topics on early universe cosmology and particle physics** [PDF]

@ 2nd Summer School on Field, String, and Holographic Theories, Southeastern University

The summer school was more oriented towards hep-th as is clear from the title. My course consists of four 90min lectures. It was fun to review basic cosmology to students with more formal-theory background, and to give them a bit flavor of how some rather formal maths can be related to actual cosmological data. But the bulk part was still devoted to QFT in de Sitter background, with little touch on particle phenomenology.

It was a pity to deliver these lectures remotely due to COVID-19. But it also means that the (virtual) blackboard writing can be easily saved.

**Cosmological Collider Physics** [PDF]

@ Pre-SUSY summer school 2021

A 90-min introduction to inflationary cosmology and cosmological collider physics. I believed that the audiences were mostly graduate students so tried to include a bit of technical details.

**Topics on Particles Physics in de Sitter Space**

@ Tsinghua, fall semester 2020

This is a set of informal lectures I gave to students and postdocs at our theory group at Tsinghua. I gave a 2hr lecture on each Wednesday evening, and eventually we had 10 lectures in total. My original (way too ambitious) plan was to talk about:

1) The cosmic inflation, its model building and its perturbation theory;

2) The more formal part of QFT in dS, including the field quantization, dS isometries and its group representations, choice of vacuum states, thermal nature of BD state;

3) The path integral formalism for calculating cosmic correlators, non-Gaussianities, cosmological collider physics; 4) Infrared issues of field theory in dS;

5) Amplitude techniques for cosmic correlators.

But it turned out that I managed to cover only 1) – 3), which already include a lot of things. My hope was that students armed with these materials would be ready to do some real works in cosmological collider physics.

My plan was to develop it more in the future, possibly into a formal course. So for now I do not have a note ready to share. An O(15%) fraction of materials, however, can be found from the summer school at southeastern university, which you can find above.

**Cosmic Inflation and Particle Physics** [PDF]

@ Summer school for undergraduate students on theoretical physics and particle physics, Peking University

A light weight introduction to cosmic inflation and cosmological collider physics to 2nd year and 3rd year undergrads. The lecture was given again at the same summer school in 2021 with very little changes.