The sixth day after power outage

Just passed the fifth night without power, it is getting very tiring. I only come back home to sleep and staying in office the whole day. I am kind of lucky that still haven’t got sick yet. But I am not so sure if this continues for another week. I couldn’t sleep well at all…

A not so rigorous introduction to finite fields

Field is meant to extend the most basic set of mathematical operations: addition, subtraction, multiplication, and division beyond real number. As subtraction and division are really inverse operations of addition and multiplication, we actually only need to consider the latter two. The set of all real numbers are closed under addition and multiplication. In the…

The second day without power

It is Tuesday night. I have never gone through a power outage lasting that long. According to the news, electricity can take a week or more to be fully restored. About one third here has no power in Tulsa. There is no traffic light in many roads, even the bigger one. I was quite a…

About method of types

Question: I was confused on the proof of Theorem 11.1.3 in yersterday’s class. And I am still confused after review the book and your notes many many times. I think that one of key points of Theorem 11.1.3 is that, under any source distribution $latex Q(x)$, the upper bound and the lower bound is true…