Last weekend was dominated by two things… a long technical post, and a football game.
I know better than to put five examples into one technical post… on the other hand, I think each one of them was a simple example. (Of course I think that; after all, I both planned and executed them.) It just took a long time to put it all together, and I didn’t get much else done. That’s hardly surprising.
As for the football game, if you follow these things you know that the Pittsburgh Steelers won last weekend and will be playing the New York Jets for the AFC championship this Sunday afternoon. Well, I won’t be doing mathematics Sunday afternoon.
Yes, I plan to put out another post for Monday. But I guarantee it will be shorter than the last one… I will simply split it into pieces, one of which can be finished today or early tomorrow. Whatever gets done will constitute the post.
I did make a little time in the evenings to make progress in Dummit & Foote’s “abstract algebra”. I think it’s going to be a challenge to get through the entire book in 10 months. That saddens me, because there are so many math books I want to get through… I simply don’t have enough time for all of them. (It would help if I stopped buying new books, but that’s inconceivable. So my reading lists keeps growing instead of shrinking.) In the meantime, I’ll keep trying to get through this book in less than a year.
I also found something new and interesting on the Internet. (Can you imagine that?)
There is apparently new software called “stack exchange”, which permits its administrators to manage a question-and-answer site. And sites are popping up in a wide variety of subjects.
In particular, there are at least two different stack exchange mathematics sites.
An easy way for you to see one is to go to this one in particular:
Note the heading across the very top:
“…for people studying math at any level and professionals in related fields…”
That is, this is not a Q&A site for research level mathematics; it’s for everything short of that. (If it’s research level mathematics you want, then go here instead: )
Oh, let me point out the major benefit of such a site; it’s the same benefit associated with usenet newsgroups: you may get multiple answers. As I have said before, and others said it before me, the quickest way to get an answer on usenet is to post a wrong answer, not to simply ask a question. People who can’t be bothered to answer the question will take the time to correct a wrong answer or to elaborate on a poor one. Like usenet, stack exchange encourages people to correct other people’s answers.
Anyway, I find it all too easy to spend an hour looking through questions on the non-research site, wondering where the time went. I haven’t registered… I haven’t answered any questions… but I’ve already seen a few for which an appropriate answer would be “I have a blog post that would provide more information”.
(Let’s see. There’s a person struggling to represent rotations as quaternions… another trying to remember the rules of logic… another who wants to know why a soccer ball has 12 pentagons and 20 hexagons….)
So far, the major hassle is finding a question a second time. If you find a stack exchange site interesting, I strongly suggest that you create a folder in your bookmarks, and throw the URL of every interesting question into it so that you’ve got the links handy. (Yes, each question has its own URL.)
Oh, there are a couple of sites which list stack exchange sites, but they seem out of date; instead you might search for “physics stack exchange”, for example, to see what’s out there in physics, and so on.
There was a much different question out there that caught my eye, asking which one result in mathematics surprised you the most.
… but I think I’ll talk about surprising results down the road, in a weekend when I don’t have other obligations — okay, other amusements — than mathematics.
Now I have a technical post to write….