My Laptop and Battery

I plan to buy a ThinkPad X230t when Windows 8 is officially released. So today, I searched the reviews on ThinkPad X230t online. One reviews was especially interesting to me. It’s about the running of Ubuntu 12.04 on ThinkPad X230. The author talked about how long X230 could run on battery, which was amazing.

Then I recalled that the battery of my laptop didn’t perform very well recently. It could only work less than one hour. My laptop is very old now. I bought it about 5 years ago. At that time, it’s very expensive and looked shining. I didn’t know much about how to activate the battery, and as I remembered, I only overcharged the battery once but didn’t completely discharge it. I didn’t repeat this process several times. So I guess the battery wasn’t activated completely.

At first, the battery seemed to work for a little bit more than one hour, but now, less than one hour, so I decided to initialize it. According to the Instructions, I needed to first fully charge the battery, then boot the computer, press F[2] to enter BIOS and let battery discharge. As soon as the battery drains off, charge it again before booting the computer. After fully charging the battery, start the computer and use up all the electricity. Then, repeat two or three times and battery might have a better performance.

I was Overpaid

At the end of each month, I receive an electronic pay statement. Today, when I opened the pdf file, I was startled. I was paid about 3000 dollars, which was exactly twice the money I earned in the past semester! At first, I thought the Graduate School raised the salary, so I told one of my officemate about this. But after he checked his pay statement, he only got 1600 dollars. Then I realized that there’s something wrong with my University’s payroll system.

In fact, I got overpaid last month, too. The fall semester began at Aug. 24th, so students should be paid half of the salary. But I was paid the salary for the whole month. I was confused at that time, and asked others if they got the full salary. They told me no but at the same time, they asked me if I was paid this Jun. because in Jun., we’re also paid half of the salary. At that time, I really couldn’t remember I was paid, so I said, “No, I wasn’t paid", and the problem was solved.

So today’s accident implied that I was overpaid for the past two months! I immediately called the Human Resources Service Center and told them my situation. They gave me several options and I decided to write a check to pay the money back.

Convinced My Teacher that He was Wrong

In this semester, I’m taking two courses. One is Quantum Field Theory and the other is Relativistic Quantum Mechanics. The professor teaching Relativistic Quantum Mechanics is an old professor. He has been working in my department for more than 30 years, I guess.

He is old and makes mistakes in class. In fact, he almost makes mistakes every class. Some of them are so serious that it would take a long time to correct them and we waste a lot of time. Sometimes, there’re also mistakes in his homework, and this happened again recently.

Last week, he assigned a homework, and I started working on it last weekend. The first problem seemed very simple and straightforward, but it turned out that I had a hard time finding the equation I needed. I tried many methods without any positive results. I kept calculating until I decided to look up the textbook. Quickly, I found a similar expression in the textbook and double-checked to make sure they were actually the same. After thinking about the problem twice, I finally reached the conclusion that my teacher made a new mistake and I already spent over 1 hour on it.

So today, I went to his office to tell him that he was wrong. He didn’t admit it at first, which was normal. Then we discussed together. He checked his calculation for a long time, and finally, he acknowledge his fault.

Met Church Friends

About 6 hours ago, I was in the Baptist Student Center, spending time with some church friends. I’m not a Christian but was invited by my host family who turned out to be a priest. He actually invited me twice recently, but since I was busy with my study and research, I didn’t attend their activity for the first time. In this week, I had more time and so I joined them. In fact, it’s a good chance to meet native English speakers and talk to them.

As soon as I entered the center, I met a undergraduate student who is studying physics in my Department, although his major is biology. He is such an enthusiastic man. He has the strong passion for God and when he talked, he smiled and used gestures to show how great it is that God forgave our sin. And he thanked for God and was willing to tell people God had done something great to all of us.

He also talked about his life. He told me that he got a bicycle and a car both for free! His Christian friends are really kind and they gave him the free bike and free car. When his friends told him that he could get the car, he asked how, then they said he could get it for free, and then he was surprised to say, “Why?" “Thanks for God!", replied his friends. This was a really amasing story!

Suffered from Insomnia

Yesterday afternoon, I started to study Analysis again. In fact, at the beginning of the summer vacation, I planned to spend at least one afternoon studying different math courses, including Analysis. But since I had to take TOEFL test, I stopped learning physics and math one month ahead of the test. Then I went to Fermilab in Batavia, IL to attend a summer school, which I will write about in the future.

3 weeks ago, I came back to my university from Fermilab and the new semester began 3 days after I returned. You know, I had already not studied Analysis for about one and a half months, so I needed to review it. That’s what I did in the first two weeks in the new semester. And in last weekend, I got the chance to study something new. It’s not a good idea to just read the textbook, but you’ve got to solve the problems. So I tried to do excises. The first few questions were quite simple and straightforward. Then I came across a more difficult one. I thought about it for a long time but couldn’t figure out how to solve it. Because it’s the time to have supper, I went back home. When I was cooking, I still thought about it.

It seemed that I wouldn’t solve the problem, but miracle happened. I usually have a hard time falling asleep, and yesterday night was no exception. So I decided to think about that problem again. It turned out I suddenly found the solution! I was so excited that I continued to try solving other problems since the beginning of the semester. However, this kept me from falling asleep, and I almost got insomnia all night!

I had a bad day today

My car got discharged again! I couldn’t believe it because I drove my car for more than 20 min yesterday after my old roommate jumped it up. Actually, I forgot to turn off the lights once about 2 weeks ago, and my old roommate helped me charge it. But I just drove it for just 5 min or so, so the next day, I couldn’t start up it again. So I called him to jump it. He then told me that I had to drive the car over 20 min, so I did that night and could start it the next day.

But this didn’t work for this time! I really couldn’t understand!

There was another bad thing happening today. This was a problem with my code. Similar problem happened days ago actually, but I didn’t realize the real problem. I just thought I might have used the wrong file. Because of the wrong judgment, I continued submitting many more simulations, and thought that everything was fine until today when I looked at the summary file. I found out that my code couldn’t modify the value of the number of the extra dimensions. This was really wired, since I actually used similar code many times without any problem. I did make some changes to the code, but that shouldn’t cause any difference. I finally found the solution to my problem, but I have already wasted a lot of time.

My Car Got Discharged

2012.09.04

Yesterday, it was raining heavily and there were several thunders. One of them, the biggest one, caused a sudden shut down of the electricity. Fortunately, it didn’t lead to serious problem. The electricity was recovered automatically very soon.

Today is the time to turn in the rent. After a short nap at noon, I wrote a check and then walked to my white car. I started up the car, but it didn’t work. Then, I opened the door and found out that the lights didn’t flash. I guessed there wasn’t charge in the battery. So I checked if I hadn’t turn off the lights. Yes, I turned them off. Then it was wired.

Suddenly, an idea occurred to my mind, it was the thunder! The thunder was so strong that it totally discharged the battery. Although I figured out the reason, I still had to pay the rent, and I had got to walk to the landlord’s office. That was a long trip. Usually, it took about 10 min to get there by car. But for this time, I might spend half an hour on the way. And the weather wasn’t very good. At first, it rained a little bit, and then, it became sunny when the temperature raised very fast. Since it has been raining for like one week, the atmosphere was very humid, so I felt very uncomfortable on the road.

But the walk really did me some good. I saw the different scenery than before. In the past, I drove my car when I had to focus my attention on the traffic. So I never noticed the beautiful scenery. Today, I got the chance because of the thunder. I wasn’t sure if I should thank it or not.

Fixed one problem

This morning, I woke up at 7 o’clock. As I planned, I should jog but I felt so tired that I stayed at home. Plus, the weather wasn’t very well, which was another good reason I didn’t jog this morning.

The breakfast was cheesecake. I don’t like cheesecake, but I still bought one to try. I really regret my stupid decision. After the breakfast, I went to my office. As usual, I listened to English on my way and tried to imitate the speakers. Since today is Labor Day, there was almost nobody on the road, so I could speak loudly.

When I arrived at my office, it’s almost 8:30, and I immediately started with my work. I am doing a simulation and I got some results this morning which I needed to analyze. It turned out that I made several stupid mistakes when I analyzed the data. I wrote a simple C++ code to count the number of scattering events whose transverse momenta are greater than a specified value. Those momenta are generated by some Monte Carlo generator and they’re double floats. But I defined an integer variable to read them, so I got very strange results.

At the beginning, I didn’t realize anything wired. But after having finished analysis, I got the interest to count the number of events by myself. Then I was surprised! After trail and fail, I finally solved the problem and got really good curves. But it took me 1 more hour. I should’ve been more careful.

I like it. Thanks to John Baez

Azimuth

The Coxeter group of the cube

Coxeter groups are a huge amount of fun. Normally their delights are reserved for people who have already studied group theory. But I don’t think that’s fair. You don’t need to know music theory to enjoy a piece by Bach. And you don’t need to know group theory to enjoy Coxeter groups.

In fact, it’s probably better to learn theories after falling in love with some examples. Imagine a world where you had to learn music theory before listening to music. A world where everyone studied music theory in elementary school, high school and college, but only people who majored in music were allowed to listen to the stuff. In that world, people might say they hate music… just as in this world they say they hate math.

So, here goes:

Last time I showed you that any Platonic solid has a bunch…

View original post 詳見內文：約1,511字

很想去

據説暑假Fermilab 會有活動，想去一下。但願目前的程序問題能很快解決掉。