Mark Chu-Carroll (aka MarkCC) is a PhD Computer Scientist, who works for Google as a Software Engineer. My professional interests center on programming languages and tools, and how to improve the languages and tools that are used for building complex software systems.
This post started out as a response to a question in the comments of my last post on groupoids. Answering those questions, and thinking more about the answers while sitting on the train during my commute, I realized that...
In my introduction to groupoids, I mentioned that if you have a groupoid, you can find groups within it. Given a groupoid in categorical form, if you take any object in the groupoid, and collect up the paths through...
Today's entry is short, but sweet. I wanted to write something longer, but I'm very busy at work, so this is what you get. I think it's worth posting despite its brevity. When we look at groups, one of...
So far, I've spent some time talking about groups and what they mean. I've also given a brief look at the structures that can be built by adding properties and operations to groups - specifically rings and fields. Now,...
When we start looking at fields, there are a collection of properties that are interesting. The simplest one - and the one which explains the property of the nimbers that makes them so strange - is called the characteristic...
When I learned abstract algebra, we very nearly skipped over rings. Basically, we spent a ton of time talking about groups; then we talked about rings pretty much as a stepping stone to fields. Since then, I've learned more...
If you're looking at groups, you're looking at an abstraction of the idea of numbers, to try to reduce it to minimal properties. As I've already explained, a group is a set of values with one operation, and which...
After that nasty diversion into economics and politics, we now return to your regularly scheduled math blogging. And what a relief! In celebration, today I'll give you something short, sweet, and beautiful: quotient groups. To me, this is a...
In my last post on group theory, I screwed up a bit in presenting an example. The example was using a pentagram as an illustration of something called a permutation group. Of course, in my attempt to simplify it...
In the last post, I talked about what symmetry means. A symmetry is an immunity to some kind of transformation. But I left the idea of transformation informal and intuitive. In this post, I'm going to move towards formalizing...