Seminar series
Date
Thu, 18 Nov 2010
Time
16:00 -
17:00
Location
L3
Speaker
Dr S Zwegers
Organisation
University College, Dublin
We consider certain q-series depending on parameters (A,B,C), where A is
a positive definite r times r matrix, B is a r-vector and C is a scalar,
and ask when these q-series are modular forms. Werner Nahm (DIAS) has
formulated a partial answer to this question: he conjectured a criterion
for which A's can occur, in terms of torsion in the Bloch group. For the
case r=1, the conjecture has been show to hold by Don Zagier (MPIM and
CdF). For r=2, Masha Vlasenko (MPIM) has recently found a
counterexample. In this talk we'll discuss various aspects of Nahm's conjecture.