Venue
Online
Speaker
Mr. Archisman Bhattacharjee
Affiliation
SMS, NISER
Title
Quadratic forms and their universality
We start with defining binary quadratic forms and discussing some properties of them. Given an integer, we look for the forms representing that. We define a composition rule for forms and define the class group. Universal forms represent every integer. We present a theorem on the classification of universal binary quadratic forms. Finally, we discuss Ramanujan's universal quaternary diagonal quadratic forms and give formulas for the number of representations of an integer by some of those forms.