Date and Time: Monday 01 April, 10:30 am - 12:00 pm.
Venue: Ramanujan Hall, Department of Mathematics.
Title: On Shalev's conjecture for type A_n and {}^2A_n.
Abstract: Let G be a group and w a word map on G. Shalev and others
computed bounds for |w(G)|/|G| when G is a finite simple group of Lie type
and showed that the lower bound is c/n except for type A_n and {}^2A_n. He
further conjectured that the same bound is expected for these cases as
well. In this talk, we present our exploration in this direction
Time:
3:30pm-4:30pm
Location:
Ramanujan Hall, Department of Mathematics
Description:
Statistics Seminar.
Speaker: Ujjwal Das.
Affiliation: IIM Udaipur, Rajasthan.
Date and Time: Tuesday 02 April, 3:30 pm - 4:30 pm.
Venue: Ramanujan Hall, Department of Mathematics.
Title: Inference on zero inflated ordinal models with semiparametric link.
Abstract: In socioeconomic and Biological studies, observations on
individuals are often observed longitudinally on a Likert-type scale with
substantially large proportion of zeros. This leads to a special case of
mixture structured data where extra-variation occurs. Obviously the
standard ordinal data analysis fails to provide appropriate statistical
inference. We propose a suitable zero inflated semi parametric ordinal
model that takes into account the non linear link between the ordinal
response and a covariate. A sieve maximum likelihood estimator(MLE) is
proposed for the regression parameter of interest. We also propose a test
for the zero proportion in this semi parametric model. A simulation study
has been carried out to investigate the performance of the estimator as
well as the test.
Time:
3:00pm-3:50pm
Location:
Ramanujan Hall, Department of Mathematics
Description:
Popular Talk.
Speaker: Harsha Hutridurga.
Date and Time: Wednesday 03 April, 3:00 pm - 3:50 pm.
Venue: Ramanujan Hall, Department of Mathematics.
Title: Intrigue of Invisibility cloaking.
Abstract: Rendering objects or oneself invisible to others has fascinated
us since the dawn of human civilization. Illustration of such vanishing
acts are often made in sci-fi movies. Even though this idea of making
oneself invisible to others sounds out of reach, lately it is gaining
traction in the scientific community. This has led to the emergence of a
fascinating field of meta-materials which deals with the design and study
of assemblies of ordinary materials such that the assembly as a whole
behaves in an exotic manner. This talk will try to present some elementary
ideas involved in the theory of invisibility cloaking. The talk is
intended for non-experts and will be accessible to people familiar with
basic notions in multivariable calculus.
Time:
4:00pm-5:00pm
Location:
Ramanujan Hall, Department of Mathematics
Description:
Department Colloquium.
Speaker: Rachel Kuske.
Affiliation: Georgia Tech.
Date and Time: Wednesday 03 April, 4:00 pm - 5:00 pm.
Venue: Ramanujan Hall, Department of Mathematics.
Title: Prevalence of heavy-tailed distributions in systems with multiple
scales: insights through stochastic averaging.
Abstract: Heavy tailed distributions have been shown to be consistent with
data in a variety of systems with multiple time scales. Recently,
increasing attention has appeared in different phenomena related to
climate. For example, correlated additive and multiplicative (CAM)
Gaussian noise, with infinite variance or heavy tails in certain parameter
regimes, has received increased attention in the context of atmosphere
and ocean dynamics. We discuss how CAM noise can appear generically in
many reduced models. Then we show how reduced models for systems driven by
fast linear CAM noise processes can be connected with the stochastic
averaging for multiple scales systems driven by alpha-stable processes. We
identify the conditions under which the approximation of a CAM noise
process is valid in the averaged system, and illustrate methods using
effectively equivalent fast, infinite-variance processes. These
applications motivate new stochastic averaging results for systems with
fast processes driven by heavy-tailed noise. We develop these results for
the case of alpha-stable noise, and discuss open problems for identifying
appropriate heavy tailed distributions for these multiple scale systems.
This is joint work with Prof. Adam Monahan (U Victoria) and Dr. Will
Thompson (UBC/NMi Metrology and Gaming).
Time:
3:30pm-5:00pm
Location:
Ramanujan Hall, Department of Mathematics
Description:
Algebraic K-Theory Seminar.
Speaker: Manoj Keshari.
Date and Time: Friday 05 April, 3:30 pm - 5:00 pm.
Venue: Ramanujan Hall, Department of Mathematics.
Title: K_0 of a ring (2nd lecture).
Time:
5:15pm-6:30pm
Location:
Ramanujan Hall, Department of Mathematics
Description:
CACAAG Seminar.
Speaker: Madhusudan Manjunath.
Date and Time: Friday 05 April, 5:15 pm - 6:30 pm.
Venue: Ramanujan Hall, Department of Mathematics.
Title: Lorenzini Zeta Function of a Graph.
Abstract: We will see a two variable zeta function associated with a graph
due to Dino Lorenzini. I will mainly spend time discussing divisor theory
on graphs that arises in the definition of this zeta function.