Abstract: Over the last decade, a Brill-Noether theory for tropical curves
analogous to the corresponding theory for algebraic curves has taken
shape.
This was discussed by Ashwin Deopurkar in the first few
CACAAG talks. I will sketch the proof of the nonexistence part of the
Brill-Noether theorem for tropical curves. This is based on the paper ``A
tropical proof of the Brill-Noether Theorem'' by Cools,Draisma,Payne and
Robeva.
Time:
11:30am - 1:00pm
Location:
Room No. 215, Department of Mathematics
Description:
Commutative algebra seminar
speaker: H. Ananthnarayan
Venue: MA 215
Date:April 3
Time: 11.30-1.00
Title: Monomial Basis of a Quotient Ring
Abstract: A polynomial ring S over a field k has a basis consisting of
monomials. Given a quotient ring R of S, one would like to identify the
monomials whose images form a k-basis of R. We will discuss the ideas of a
monomial order, and initial ideals, leading to Groebner basis, which help
answer this question.
Time:
4:00pm
Location:
Ramanujan Hall, Department of Mathematics
Description:
Mathematics Colloquium
Date & Time: 4th April, 2018 at 4pm
Venue: Ramanujan Hall
Speaker: Manoj Gopalkrishnan
Title: Imagining how a cell thinks: The design of reaction network schemes
that do machine learning
Abstract: A living cell responds in sophisticated ways to its environment.
Such behavior is all the more remarkable when one considers that a cell is
a bag of molecules. A detailed algorithmic explanation is required for how
a network of chemical reactions can produce sophisticated behavior. Several
previous works have shown that reaction networks are computationally
universal and can, in principle, implement any algorithm. The problem is
that these constructions have not mapped well onto biological reality, have
made wasteful use of the computational potential of the native dynamics of
reaction networks, and have not made any contact with statistical
mechanics. We seek to address these problems.
We find that the mathematical structure of reaction networks is
particularly well suited to implementing modern machine learning
algorithms. We describe a new reaction network scheme for solving a large
class of statistical problems including the problem of how a cell would
infer its environment from receptor-ligand bindings. Specificially we show
how reaction networks can implement information projection, and
consequently a generalized Expectation-Maximization algorithm, to solve
maximum likelihood estimation problems in partially-observed exponential
families on categorical data. Our scheme can be thought of as an
algorithmic interpretation of E. T. Jaynes's vision of statistical
mechanics as statistical inference.
Time:
2:00pm - 3:30pm
Location:
Room No. 105, Department of Mathematics
Description:
PDE seminar
Date and Time: April 5, Thursday, 2-3:30 p.m.
Venue: Room 105, Mathematics Department
Title: Control of infinite dimensional linear systems
Speaker: Dr. Debanjana Mitra,
Abstract: First, we recall semigroup theory. Using this, we study the
controllability and stabilizability of linear partial differential
equations. In details, th
Time:
11:00am
Location:
Ramanujan Hall, Department of Mathematics
Description:
Combinatorics Seminar
Title: Galois Coverings of Schreier Graphs
Speaker: Asif Shaikh (R A Podar College of Commerce and Economics)
Date-Time: Monday, April 9 2018, 11 AM to 12.30 PM.
Venue: Ramanujan Hall
Abstract: Attached.
Time:
2:15pm
Location:
Ramanujan Hall, Department of Mathematics
Description:
CACAAG seminar
Date & Time : 9th April, 2:15pm
Venue: Ramanujan Hall
Speaker: Saurav Bhaumik
title: Voisin's proof of the Green's Conjecture
Abstract: We will give a rough idea of Voisin's proof of the Green's
Conjecture in the even genus case.
Time:
4:00pm
Location:
Ramanujan Hall, Department of Mathematics
Description:
Popular Lecture in Mathematics
Speaker: Sachin Garg (MSc 2nd Year)
Date & Time : 11th April 2018 at 4:00 PM
Venue: Ramanujan Hall.
Title: Multiplicative Weights Update
Abstract: Problem at hand: Suppose you have the choice of taking one of the
"n" decisions every day which will consequently put you to certain loss
which is not known apriori
What shall you do to "*minimize*" the loss?
Let's meet and concrete out a strategy this Wednesday at Popular Talk.
Time:
2:00pm - 3:30pm
Location:
Room No. 105, Department of Mathematics
Description:
PDE seminar
Date and Time: April 12, Thursday, 2-3:30 p.m.
Venue: Room 105, Mathematics Department
Title: Control of infinite dimensional linear systems
Speaker: Debanjana Mitra,
Abstract: In the continuation of the lecture on 5th April, we complete the
discussion on semigroup theory. Using this, we study the controllability
and stabilizability of linear partial differential equations. In details,
the control of transport, heat and wave equations will be discussed.
Time:
2:15pm
Location:
Ramanujan Hall, Department of Mathematics
Description:
CACAAG seminar
Date & Time : 16th April, 2:15pm
Venue: Ramanujan Hall
Speaker: Sudarshan Gurjar
Topic: Vector bundles on Compact Riemann Surfaces
Abstract: Holomorphic vector bundles on compact Riemann surfaces and its
other avatar, namely algebraic vector bundles on smooth, complex
projective curves has a long and rich history with important contributions
by the Indian Algebraic Geometry school. I will introduce this subject
with special focus on bundles which come from representations of the
fundamental group of the surface. Much of the talk will be accessible to
Ph.D students.
Time:
11:30am - 1:00pm
Location:
Room No. 215, Department of Mathematics
Description:
Commutative algebra seminar
Venue: MA 215
Date and time: Tuesday, 11.30 am-1 pm.
Speaker: H. Ananthnarayan
Title: Initial ideals and applications
Abstract: In the previous talk, we saw that given an ideal I in a
polynomial ring R, the monomials not in the initial ideal of I form a
basis of R/I. In this talk, we will see further examples of how to use the
initial ideal of I to get more information about I (or R/I).
Time:
2:00pm - 3:30pm
Location:
Room No. 105, Department of Mathematics
Description:
PDE seminar
Date and Time: April 19, Thursday, 2-3:30 p.m.
Venue: Room 105, Mathematics Department
Title: Control of infinite dimensional linear systems
Speaker: Debanjana Mitra
Abstract: We continue the discussion of the asymptotic behavior of a C_0
semigroup. Then, the different notions of controllability of a linear
system in infinite dimension will be introduced in an abstract set up. For
example, we study the heat equation in details.
Time:
2:30pm - 3:30pm
Location:
Ramanujan Hall, Department of Mathematics
Description:
Title: Deep Inside Data in Dimensions One, Two, Three, ... , Infinity
Speaker: Prof. Probal Chaudhuri
Theoretical Statistics and Mathematics Unit
Indian Statistical Institute, Kolkata
Abstract: Prof. Chaudhuri has not given the abstract to keep the matter a
little mysterious!!
Date: 19/04/2018 Time: 2:30 pm to 3:30 pm Venue: Ramanujan Hall
Time:
3:00pm
Location:
Ramanujan Hall, Department of Mathematics
Description:
Analysis Seminar
Date & Time : 23rd April, 2018 Monday at 3pm.
Speaker: Prof. Kalyan B. Sinha, Jawharlal Nehru Centre for Advanced Scientific Research, Bangalore and IISc Bangalore.
Venue: Ramanujan Hall
Title : Trace Formulas in Operator Theory
Abstract ; The celebrated Helton-Howe trace formula for hyponormal
operators is derived as a consequence of Krein's trace formula .
In many situation trace is a 'special' non-commutative integral of
'operator-functions ' and the said formula relates the non-commutative
integral with the 'volume Lebegue integral' ( in the usual
commutative sense ) .
Time:
4:00pm - 5:00pm
Location:
Ramanujan Hall, Department of Mathematics
Description:
Mathematics Colloquium
Speaker: Prof. Parthanil Roy
Stat-Math Unit, ISI Bangalore
Date and Time: Tuesday 24th April, 2018; 4 p.m. to 5 p.m.
Venue: Ramanujan Hall
Title: Branching Random Walks: Two Conjectures, Two Theorems and a Question
Abstract: Branching random walk arises naturally in mathematical biology,
statistical physics and probability theory. Roughly speaking, it models a
system of growing particles or organisms that invades an environment in a
systematic fashion. Two famous statistical physicists (Eric Brunet and
Bernard Derrida) made conjectures about the long run configurations of
positions of particles in a branching random walk, and asked an open
question in their seminal work in 2011. Their question was answered
positively by Maillard (2013), and the conjectures were mathematically
proved recently by Madaule (2017) under certain conditions. In this talk,
we shall concentrate on the PhD thesis of Ayan Bhattacharya, who verified
Brunet-Derrida conjectures outside the Maillard-Madaule setup. If time
permits, some other recent related work will also be discussed.
This talk will be based on joint work with Ayan Bhattcharya and Rajat
Subhra Hazra. The papers are available in https://arxiv.org/abs/1411.5646
and https://arxiv.org/abs/1601.01656.
Time:
2:00pm - 3:30pm
Location:
Room No. 105, Department of Mathematics
Description:
PDE seminar
Date and Time: April 26, Thursday, 2-3:30 p.m.
Venue: Room 105, Mathematics Department
Title: Control of infinite dimensional linear systems
Speaker: Debanjana Mitra,
Last talk of this seminar series for this semester.
Abstract: We discuss on feedback stabilizability of the infinite
dimensional system via the solution of Riccati equation. We touch upon
some interesting aspects of an optimal control problem. At the end, if
possible, we shall discuss on some interesting open problems in this
direction.
Time:
4:00pm - 5:00pm
Location:
Ramanujan Hall, Department of Mathematics
Description:
Date and Time: 26th April, 4-5p.m
Venue: Ramanujan hall
Title: Mathematical Analysis of a Rigid Body in a Viscous Gas.
Abstract :
Fluid-structure interaction problems have been an important area of
research in recent years. Such systems occur, for instance, in
aerodynamics (flow around an aircraft), medicine (blood flow in vessels),
zoology (swimming of aquatic animals). The mathematical study of these
problems rises several challenges, the main one being due to the fact that
the domain filled by the fluid is one of the unknowns of the problem. In
this talk, we present some recent advances in the mathematical analysis of
some particulate flows. We show that a variety of such system admits a
global in time unique solution for small initial data in the $L^p$ - $L^q$
framework.