About This Blog

This blog is in general for educational purposes in mathematics and for writing down what I've done. Not trying to 'show off' something but hope I can help some random people on the Internet or simply myself (when my memory does not go pretty well). I guarantee no perfectness of my post but I'll do my best. If you want to make a reference to my posts or using it for educational purposes, the only price is letting me know (see the email down below).

The only third-party plugin used in this blog is MathJax. I have no idea how to harvest data from MathJax. The only way that I can collect data is through Google Search Console, and the data is on Google's search page. I'm honest. If people think it is not OK then I will remove it. Other than this I have no method to know the popularity of my blog posts. (No, I have no idea which links you click on my site and I have no idea how long you stay or when you visit. Maybe I'm not smart enough.)

Anyway, I'm not an IT guy or a geek (I prefer calling myself ageek, a- for asocial), the only thing I can ensure is your reading experience. I hope the reader can calm down and focus until finish reading. I hope the reading can solve the reader's problem or let him or her have a good time in mathematics. And you will never see me here as an activist or purist, urging you to do something or cut yourself out of something for some big reasons, like boycotting stuff. Although it may be good under certain circumstances, I know you must be very tired of this and the five lemma is not a political matter. Besides, there will not be content related to competitive maths. I never get the point of competition. I don't like to play video games competitively. And I don't think I will ever be an athlete.

This blog does not offer any print service. However, if you want to read my posts offline, it's recommended to print the page into PDF with the help of browser extensions (edit: save-as-pdf extension seems not so satisfying. I will think about a better way to do it if many people ask for it). You may also ask for the original markdown file from myself (for free). I left my email address at the bottom.

There is no way to ensure that my posts are readable for everyone. The background of the reader varies a lot and I cannot control it. If I want to make my post readable to everyone or a lot of people, I guess I have to do maths popularisation. Some people are good at popularising mathematics and did an excellent job (also some people are good at overly exaggerating things, creating nonsense drama, clickbaiting, and claiming whatever "counterintuitive" as paradox), but I'm not that kind of person. I prefer pen and paper, chalk and blackboard (and LaTeX), formality and rigour.

One of the reasons for me to run this blog (at a cost of 10$/year) is, to remove the inexplicit barrier to information, or say to fight against information asymmetry. Let's admit it - sometimes it is extremely hard (and frustrating!) to get the resources we want. And Stack Exchange websites can be "unforgiving" (I deleted my Math Stack Exchange profile because I'm really tired of it, but I will not write a post explaining it). I want to be the one of change, so random students like you and me will not feel 'being trivialised personally'.

But I can't and shan't take care of everyone's background. When writing a post, I will set a default knowledge background and mathematical maturity for the reader (most of the time I assume the reader is a maths major student interested in pure maths, just like me; of course in my algebra posts I shan't assume a strong background in analysis). Of course, I wouldn't write something like "we refer the reader to Bourbaki" when it is not okay to assume the ability to read his works. But there is something that everyone has to overcome in order to be stronger. We need patience and to be ready to work on some hard problems for a long time, and it's always a stupid take to ask 'how to study maths really quick', or you have been pranked by me already. Study is not an easy job. No matter how "legendarily smart" you are, or how high your IQ is, you need some hard work. Mathematicians struggled much more.

Updated 26/08/2022: I may rebuild this blog after reaching 100 posts because the interface is not that great, and the table of content is weird. Of course it does not mean any paywall.


Mail me via d_blog_contact#protonmail.com (# -> @). Alternatively, if you have subscribed to my newsletter, you can simply reply to any email you receive from my newsletter at any time.

As long as you are not spam or scam, like saying that I will be a millionaire by submitting my personal information (I received such a funny letter from a self-acclaimed bank manager, asking me to help him to do illegal things or something like that), I will reply to your email. I may not reply very soon but I am not ignoring emails with reasonable purposes.

If you find anything mathematically wrong in my posts, please let me know!



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