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.
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.
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.
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.
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.
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.
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.
本文的中文版请点击这里
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.
Here are a few things that I want to achieve in 2019.
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.
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:
I learned a lot of physics in 2018, and here is a summary!
In January, I finished 8.04x, Quantum Mechanics an online course provided by MITx and got perfect grades, 92, 94, and 88 for three exams. 8.04x was lectured by Professor Barton Zwiebach, whose doctoral advisor is Murray Gell-mann. This course introduced basic concepts of Quantum Mechanics and did standard 1-D potential examples, such as square wells, Dirac-delta potential and harmonic oscillators, along with several important theorems for 1-D potential. Besides, it gave a detailed treatment on scattering states in 1-D, covering topics like time delay, Levinson’s theorem and resonance. The course ended with central potential and Hydrogen Atom. It was a challenging but rewarding course, and of course, interesting! What makes this course stand out among all other online courses is its active discussion forum. I met lots of interesting physics and math geeks there, Mark, Jolyon, Jim, BlueFlow and Jonathan, and the discussion about physics with them made my learn experience vivid and lovely (Actually, I read their discussions in forum most of the time). Later in September 2018, Jim offered me an unexpected research experience, which was the first time I worked with a real physicist!