MathOverflow is a question and answer site for professional mathematicians. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Sorry about asking so many questions, but I had an idea for my study of groups, and I wanted to know if it was already a thing people use. My idea is to make a multiplication table with all the conjugacy classes of a group. In each box, there would be a list of the possible conjugacy classes that you could get from multiplying the specified two conjugacy classes together.

Is this something new, and would it be useful in the study of some groups?

share|cite|improve this question

closed as off-topic by Benjamin Steinberg, Steven Landsburg, Andrey Rekalo, Chris Godsil, David White Sep 19 '13 at 17:53

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "This question does not appear to be about research level mathematics within the scope defined in the help center." – Steven Landsburg, Chris Godsil, David White
If this question can be reworded to fit the rules in the help center, please edit the question.

This is a pretty standard idea. Have a look at an introductory textbook. Not entirely related, but you might get a kick out of character tables too. Voting to close. – David White Sep 19 '13 at 17:53

The numbers are called class multiplication coefficients. Definitely not something new! Knowing them and the size of the conjugacy classes, you have the structure constants for the center of the group algebra. There is some discussion of using them computationally in 2.3 of Lux-Pahlings book. There are actual tables of them for the symmetric group in the back of Kerber's book.

share|cite|improve this answer
Oh good, they actually have a use after all! Could you provide a link to those books? – Thomas Sep 19 '13 at 13:54

Not the answer you're looking for? Browse other questions tagged or ask your own question.