# Perils of Modern Living: Blogging Edition

With all of its benefits, there are many difficulties of life that are unique to civilization: traffic, taxes, pollution. Thanks to blogging, I’ve experienced a new one: having your WordPress site hacked. The hosting company shut down the site because it was receiving unusual traffic. Upon further investigation, it turned out the site had been hacked. (Presumably the traffic was from the site being made part of a botnet.) It should now be fixed.

# Experimenting with MathJax

I’m experimenting with MathJax to include mathematics on the blog. Part of the incredible slowness in which I write posts is doing everything by hand in HTML. For example, I have a future post for the Horn clause series that I keep not finishing because I get tired of writing the subscript tags. MathJax is the display engine used for Math Overflow and Stack Exchange, which allows you to use tex commands to represent formulas.

Here’s a sample of tex-encoded math formulas that I copied from the MathJax site.

When $a \ne 0$, there are two solutions to $$ax^2 + bx + c = 0$$ and they are $$x = {-b \pm \sqrt{b^2-4ac} \over 2a}.$$

If you actually view the source for the file in your browser, you’ll see the raw tex commands in the post. MathJax uses CSS to render it on the fly. I’m actually surprised this is possible, but apparently it is.

# Back, From Outer Space!

And you just walked in to find me here with that sad look upon my face.

The computer that hosted Ars Math (which was at a dedicated web-site hosting company) died a horrible death a couple of months ago. For a while, it looked like several years of posts had been lost. They could be recovered by cutting-and-pasting from the Internet Archive, but I found the idea so depressing that I didn’t do anything about recovering the site. Fortunately, we were able to extract the posts from the database anyway. Someone offered to help out with the WordPress hosting, so we’re back online!

At the moment the last couple of years of comments are missing, but we’re still investigating what happened to them.

# Tremellius and Naibod

God Plays Dice has a post that answers a question I’ve long had about the Mathematics Geneology Project: just how far back can you go? The answer is 1572, when Immanuel Tremellius and Valentine Naibod advised Rudolph Snellius. Snellius was the father of Willebrord Snellius, who discovered Snell’s law.

Tremellius was a Bible translator who was briefly jailed for being a Calvinist. It sounds like he was forced to move frequently as the prevailing winds for Protestants changed. (This was the early Reformation.) Naibod was an astrologer who had a book banned by the Catholic Church. An astrological prediction told him that his life was in danger, so he tried holing up in his house until the danger passed. Since the house showed no external signs of life, thieves thought the house was abandoned and broke in. Discovering Naibod, they murdered him. Apparently astrology works after all.

The Geneology Project has a page dedicated to what it calls extrema. I would support a campaign to rename the Guinness Book of World Records the Guinness Book of Extrema.

Update. In between when I hit “Post” and now, the Mathematical Geneology site updated their database, making this post completely obsolete.

# Perspective

I was looking at the stats for Ars Math, when I saw that we’ve had 525 posts. I thought “Wow, that’s a lot of posts.” Then my eye happened to glance at the count of the number of comments the Akismet plug-in has deleted as spam: 304,061.

# Dummit and Foote panned

Isabel at God Plays Dice finds the definitive review of Dummit and Foote, here at adequacy.org.

(If you have any questions as to the objectivity of adequacy.org, I suggest checking out their Wikipedia page.)

I had to go and unapprove a bunch more comments. I am erring on the side of removing anything provocative.

Things to know:

1. Yes, I will freely “censor” the blog. No, I don’t care how much this offends your most deeply held beliefs. Yes, I am the new Hitler/Stalin.
2. You do not a university affiliation to comment here. You can even be a crackpot. All I ask is that you keep it polite, and don’t take over unrelated threads.