Category: abstract algebra

Last time we did a lot of abstract nonsense. T…

Last time we did a lot of abstract nonsense. Today we are going to try and turn it into concrete nonsense.

Once you start taking more higher level math c…

Once you start taking more higher level math classes, you start to realize that it’s all the same. If you’re a lazy thinker, that’s good news. It’s why I became a doctor of mathematics and not an actually useful medical doctor, because that’s too much work.

Subscripts on subscripts, now that’s ser…

Subscripts on subscripts, now that’s serious math!

This theorem looks very good. In fact, it is s…

This theorem looks very good. In fact, it is so good, it really should not be true.

Representation theory is the only group theory…

Representation theory is the only group theory there is – unless your groups are simple, and it’s useless.

A permutation, according to this definition, c…

A permutation, according to this definition, could be both even and odd.  Which would be odd.

In my head, physicists do nothing but measure …

In my head, physicists do nothing but measure springs.

When we make a cone of a diagram, we put the m…

When we make a cone of a diagram, we put the morphisms on the left.  Dually, in a co-cone, the morphisms go on the… co-left.

This is called an imaginary number because you…

This is called an imaginary number because you only deal with these in your dreams.

These results should be evident. Well, the dem…

These results should be evident. Well, the demonstration is long and complicated. But evident. Yes.