**Date & Time:** Monday September 10, 2012, 15:30-17:00.

**Venue:** Ramanujan Hall

**Title:** Circular units and a generalisation

**Speaker:** Prof. Ramesh Sreekantan,
ISI Bangalore

**Abstract:** Circular units are units in cyclotomic fields given by
special values of trigonometric functions. Their norms appear
naturally as special values of zeta functions of real quadratic
fields. In this talk we will discuss a generalisation of this
situation to products of elliptic curves over the rationals - where an
analogue of a circular unit appears as a special value of the
L-function of the product of elliptic curves. Not surprisingly this
uses some classical formulas such as the Rankin-Selberg integral
formula and the Kronecker Limit formula.