Two days ago, I gave a seminar talk on Chern‘s proof of the generalized Gauss-Bonnet theorem. Here I record the answer to a question asked by one of my colleague during the talk. 497 more words

## Tags » Group Theory

#### I Don't Understand Brackets

Ups and downs. It’s been such an eventful week. So much happened that made me rethink my time schedule.

## Success

A few months ago, I’ve participated in Bundeswettbewerb Mathematik… 1,010 more words

#### Get the multiplication table of 2 by 2 matrices of integers modulo 3 - SageMath

The following code will prepare a list of two by two matrices over Z_2 and will show the group multiplication in it. Copy paste the code to a SageMath cell and try! 180 more words

#### A observation on conjugate subgroups

Let and be conjugate subgroups of , that is, for some , . Equivalently, , which means there is some element of such that under the action of on , its stabilizer subgroup is , all of the group of the group action. 68 more words

#### Group of order p^2

I discussed this theorem with my grandfather when I went to Chennai this summer. I had learnt about group actions earlier, in the context of using group actions to solve combinatorial problems. 353 more words

#### Math sunday

I had a chill day thinking about math today without any pressure whatsoever. First I figured out, calculating inductively, that the order of is . You calculate the number of -tuples of column vectors linear independent and from there derive as the number of vectors that cannot be appended if linear independence is to be preserved. 693 more words

#### Composition series

My friend after some time in industry is back in school, currently taking graduate algebra. I was today looking at one of his homework and in particular, I thought about and worked out one of the problems, which is to prove the uniqueness part of the Jordan-HÃ¶lder theorem. 138 more words