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Seeker of Truth

Working like a man means that a man feels what he is doing and thinks why and for what he does it, how he is doing it now, how it had to be done yesterday and how today, how he would have to do it tomorrow, and how it is generally best to get it done—whether there is a better way.—Gurdjieff

Summary for my favorite 2020 TV shows and books

2020 is worse than expected for everybody due to COVID-19. The pandemic started in China in February, and quickly spread world-widely. It is extremely difficult to travel oversea and the situation becomes worse after the mutation of the virus in the UK. I did not go back to China in the summer holiday as expected and there is no hope that I can go back for the up-coming 2021 Chinese new year.

Summer vacation

From late-July to mid-September is the summer vacation of our group. I moved to a dormitory of The University of Tokyo called Kashiwa-no-ha International Village (KIV) on 21st July. So I started my summer vacation by setting down at my new home.

Daily life — Moved to KIV and found an interesting book!

KIV is a nice place. Within a circle with radius 120 foots, you can get to the school shuttle bus head for Kashiwa campus in 10 minus, bus station where you can go to other places nearby, and Tsukuba Express, which can send you to center of Tokyo within an hour. A few steps away is a very large shopping center. So the traffic is perfect! Also, since many international students live in KIV, most people here are very friendly. You can easily start a casual conversation in the share kitchen, so it is a place you will never feel lonely. 

Mill and Dirac

I started to watch the famous Harvard online course Justice by Professor Michael Sandel. It mainly discusses ethics and what is the criteria for the right thing. The course started with two utilitarian philosopher Jeremy Bentham and J.S. Mill. The idea of utilitarian is generally well accepted in China according to my experience. If you ask a random person in China, whether it is right to sacrifice one people’s life for ten, the answer is probable yes. More quantitative and serious application of utilitarian lies in the study of economic. In microeconomics, the concept of utility is well-developed, and rational decision is made by maximizing utility. And many companies and investors will do cost-benefit analysis before making a decision. However, the utilitarian is only one of many criteria about the right thing. When you think about the famous law cased called The Queen v. Dudley and Stephens (1884), you notice the principle of maximizing the total utility is not always the right thing to do.

西方哲学史by张志伟(The History of Western Philosophy)

This notes will be written in Chinese, since the lecture videos I watched are in Chinese. It will be easier for me to keep track of various philosophy terminologies in Chinese first.

What I watched is a list of video lectures called The History of Western Philosophy lectured by Prof. Zhiwei Zhang in Renmin University of China. It is part of a MOOC course but the lecture videos are uploaded to Bilibili, a Chinese version of YouTube (Notice it is in Chinese). The syllabus is closely related to the table of contents of Bertrand Russell’s book, The History of Western Philosophy, which provides a detailed description of the history. Instead, these video lectures provide a brief introduction to every important philosophers in various historical periods, so it is a nice first pass for me. That’s all for the background, the following notes will be all in Chinese.

PSI 2015/2016 – Condensed Matter (TCHERNYSHYOV)

I just finished all 15 video lectures of Condensed Matter Course in PSI 2015/2016 program early today. The main lecturer of this course is Professor Oleg Tchernyshyov from Johns Hopkins University.

Lecture 6 – 10 are given by the other lecturer who is I believe the faculty member in Perimeter Institute. These four lectures talk about more mathematical contents like path integrals for Fermions, which corresponds to chapter 5 and 6 of Shankar’s QFT book (see my review of this book). The account of this lecturer is a little hard to follow and I believe this part is better to learn by doing all the derivation on one’s own, instead just watching others doing all the calculation. I’m already very familiar with free field formulation for bosons and fermions, but still not very comfortable with interactive theories. I think I would get my self familiar with this by studying Altland’s book or Orland’s book.

Review: Quantum Field Theory and Condensed Matter, An Introduction

I just finished my first pass on Shankar’s QFT book, Quantum Field Theory and Condensed Matter, An Introduction. The book ranges from the standard Ising model and path integrals topic to more advanced techniques like bosonization and quantum Hall effect, so it becomes more difficult as you proceed. I went through Chapter 1 to Chapter 15 and the remaining parts just look beyond my capability right now. Still, I feel it a very entertaining reading experience and have learned a lot in the first 15 chapters.

Plans for 2020

2020 is a special year.  The coronavirus situation has made an impact on everyone’s lives.

I went back China on 11 January for Chinese New Year. I had been in Shanghai, hanging out around my friends until 20th January, and then I went back my home in Liyang to meet my parents. There were a few rumors about coronavirus in Wuhan, Hubei even during that period. After the official announcement of coronavirus situation, Wuhan was on lockdown. The normal activities like visiting friends and relatives were all cancelled out during the Chinese New Year. I also cancelled all my schedules of meeting my friends. I stayed home until 1st February, and came back Japan on 2nd February. After a two-week self-quarantine, I finally got back to my institute (ISSP) and returned to normal life. However, this life didn’t last long. Japan entered emergent situation from early April and would end on May. During this time, we ought to work from home. All the lectures in Utokyo were given using online platform like zoom.

Summary for 2019

About Physics – Before July

As was mentioned in an early post Goals for 2019, I had worked on several courses but not finished them all. Here I will list courses that I have finished.

  1. Group Theory in a Nutshell for Physicists by Antony Zee. I finished Part I ~ VI in April.
  2. 8.06x Applications of Quantum Mechanics by Barton Zwiebach. This is an excellent course provided by MIT in edX. I have written a term paper for this course explaining the notion of a single photon. We know from high school physics that photon sometimes behaves like particles and sometimes behaves like waves. In this paper, I introduce a framework where this wave-particle duality will arise naturally.
  3. 18.6501x Fundamental of Statistics. This course exposes some basic statistics idea to me. I passed the course but didn’t take its final exam.
  4. Complex Analysis with Physical Applications by two Russian physicists: Prof. Yaroslav Rodionov and Prof. Konstantin Tikhonov. I only finished 7 out of all 9 units. I will definitely do this course again when it reruns in the future.
  5. Einstein Gravity in a Nutshell by Antony Zee. I only finished first 6 parts in the book, seeing how Einstein’s Field Equation is derived. I will reread this book and finish all of it in the future.

About Physics – July and August

I attended a workshop called Computational Approaches to Quantum Many-body Problems (CAQMP) organized by my supervisor in Japan. This is the first time I’ve ever attending a physics workshop. I just want to get myself familiar with what I will work on later. I didn’t understand most of the talks in this workshop. Most people attending this workshop were professors or postdoctors. However, I did meet a few interesting friends during this workshop.

Pursue Your Passion and Results Will Be Unexpected — Boosting Your Career Through Independent Learning

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I was trained to be a structural engineer but I want to be a theoretical physicist.

I was major in Japanese when I was a freshman in 2013. It was exciting and happy to study with so many young girls together: there are about 50 students who were major in Japanese but only five fellows! For a boy focusing on science side in high school in China, he had hardly seen over 10 girls during his whole high school life. Such a situation could not be better! Sadly, the boy read too many science popular books and was more curious about peculiar quantum mechanics, or even string theory at that time, so he decided to change his major. He first did some research on physics major in his university, but it turned out the people in the physics department look nothing like the characters in his book: Niels Bohr, Wolfgang Pauli, Richard Feynman, Albert Einstein, etc. As a result, he had to take the second best and went to civil engineering major, hoping he could meet more geek-like people there, since it was (and still is) the department with the most eminent professors and students in the country. He started his undergraduate training in structure engineering in 2014.

Goals for 2019

Here are a few things that I want to achieve in 2019.

Non-physics

I hope I can finish writing up my master thesis before September. The plan is to finish the first draft before mid July, and working on its revision starting from mid August.

About Physics

I’m so happy that The University of Tokyo (UTokyo) gives me one graduate school offer, so I can start my physics journey! Before attending UTokyo in September this year, I still need to learn more physics on my own. Here are my plans for first half year: