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IPDF Talk
Speaker: Om prakash, IIT Gandhinagar
Host: Manoj K Keshari
Date : 22nd May, Monday
Time : 4-5 pm.
Title: A Study of certain Affine Semigroups and Semigroup Rings.
Abstract: It has been proved that there is no upper bound on the Betti
numbers of a numerical semigroup ring for a fixed embedding dimension
$e\geq 4$. The same question can be asked for affine semigroup rings as
well. However, unlike numerical semigroup rings, affine semigroup rings do
not necessarily have the Cohen-Macaulay property, and the existence of
Pseudo Frobenius elements of an affine semigroup is also not guaranteed.
We will discuss some results and examples in this talk and try to show how
the Cohen-Maculayness and the pseudo-Frobenius set play an important role
in the study.
Link : https://meet.google.com/gyb-jfbn-oiu?authuser=0
Statistics/Probability job talk
Date and time: May 25, 2023 (Thursday) 3 to 4 pm
Venue: Ramanujan Hall, Department of Mathematics
Host: Murali K Srinivasan
Speaker: Ashish Mishra
Affiliation: UFPA, Brazil
Title: On quasi Steinberg characters of complex reflection groups
Abstract: Consider a finite group G and a prime number p dividing the order of G. A
p-regular element of G is an element whose order is coprime to p. An irreducible character
χ of G is called a quasi p-Steinberg character if χ(g) is nonzero for every p-regular element
g in G. A quasi p-Steinberg character χ is called weak p-Steinberg if χ has degree |G|p.
These variants of p-Steinberg character were introduced to answer a question of Dipendra
Prasad that asked whether the existence of a weak p-Steinberg character of G implies
that G is a finite group of Lie type. In this joint work with Digjoy Paul and Pooja Singla,
we classify quasi p-Steinberg characters of all finite irreducible complex reflection groups.
In the first part of the talk, we will give an overview of representation theory of complex
reflection groups.