11:30am» R.V.Gurjar- Time:
- 11:30am - 1:00pm
- Location:
- Room No. 215, Department of Mathematics
- Description:
- Time: Friday, 2nd Nov, 11:30 a.m. - 1:00 p.m.
Venue: Room 215, Maths Building.
Title: Complete modules and base conditions of linear system - II
Speaker: R.V.Gurjar
Abstract: We will discuss Zariski's theory of complete modules and their
relation to base points of linear systems.
- Time:
- 3:30pm - 5:00pm
- Location:
- Room 215, Department of Mathematics
- Description:
- Commutative Algebra seminars
Date: Monday 5 Nov
Venue: Room 215
Time: 3.30-5.00
Speaker: Clare D'Cruz
Chennai Mathematical Institute
Title: Symbolic powers of certain monomial curves
Abstract: The generators of symbolic powers of an ideal, in general, are
hard to determine. A natural question is the relation between symbolic
powers and ordinary powers. In this context, Bocci and Harbourne gave an
asymptotic quantity called resurgence. Though this is hard to determine, in
some cases it is known. In this talk, we focus on certain monomial curves.
We discuss the regularity for symbolic powers and the resurgence.
- Time:
- 2:00pm - 3:30pm
- Location:
- Room 215, Department of Mathematics
- Description:
- Date: Thursday 8 November
Venue: Room 215
Time: 2.00-3.30
Speaker: Dale Cutcosky, University of Missouri at Columbia, MO
Title: Multiplicities and volumes-I
Abstract: We show how multiplicities of (not necessarily Noetherian)
filtrations on a Noetherian ring can be computed from volumes of
appropriate Newton Okounkov bodies. We discuss applications and examples.
- Time:
- 4:00pm
- Location:
- Room 215, Department of Mathematics
- Description:
- PDE seminar on Control and homogenization:
Title: Control of wave equation.
Speaker: Debanjana Mitra,
Time: Thursday, 08-11-18, 4p.m.-5p.m.
Venue: Room 215, Department of Mathematics, IIT Bombay.
Abstract: In this talk, we will continue the discussion on the control of
wave equation from where we stopped at the previous lecture.
The observability inequality for wave equation will be proved by
multiplier method.
- Time:
- 11:30am - 1:00pm
- Location:
- Room 215, Department of Mathematics
- Description:
- Date: Friday, 9 November
Venue: Room 215
Time: 11.30-1.00
Speaker: Dale Cutcosky, University of Missouri at Columbia, MO
Title: Multiplicities and volumes-II
Abstract: We show how multiplicities of (not necessarily Noetherian)
filtrations on a Noetherian ring can be computed from volumes of
appropriate Newton Okounkov bodies. We discuss applications and examples.
- Time:
- 4:00pm - 5:00pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
- Date and time : 9th November 2018, 4.00 - 5.00 pm,
Venue: Ramanujan Hall
Title: Concentration Bounds for Stochastic Approximation with Applications
to Reinforcement Learning
Speaker: Gugan Thoppe
Affiliation: Duke University, Durham, USA
Abstract: Stochastic Approximation (SA) refers to iterative algorithms that
can be used to find optimal points or zeros of a function, given only its
noisy estimates. In this talk, I will review our recent advances in
techniques for analysing SA methods. This talk has four major parts. In the
first part, we will see a motivating application of SA to network
tomography and, alongside, discuss the convergence of a novel stochastic
Kaczmarz method. In the second part, we shall see a novel analysis approach
for non-linear SA methods in the neighbourhood of an isolated solution. The
main tools here include the Alekseev formula, which helps exactly compare
the solutions of a non-linear ODE to that of its perturbation, and a novel
concentration inequality for a sum of martingale differences. In the third
part, we will extend the previous tool to the two timescale but linear SA
setting. Here, I will also present our ongoing work to obtain tight
convergence rates in this setup. In parallel, we will also see how these
results can be applied to gradient Temporal Difference (TD) methods such as
GTD(0), GTD2, and TDC that are used in reinforcement learning. For the
analyses in the second and third parts to hold, the initial step size must
be chosen sufficiently small, depending on unknown problem-dependent
parameters; or, alternatively, one must use projections. In the fourth
part, we shall discuss a trick to obviate this in context of the one
timescale, linear TD(0) method. We strongly believe that this trick is
generalizable. We also provide here a novel expectation bound. We shall end
with some future directions.
- Time:
- 4:00pm
- Location:
- Room 215, Department of Mathematics
- Description:
- Geometry and Topology seminar
9th November, 4:00 PM
Room 215
Title. Shafarevich question on the universal covering of a smooth
projective variety, and it's applications.
Speaker. R.V. Gurjar
Abstract. I. Shafarevich has raised the following very general question.
'Is the universal covering space of every smooth connected projective
variety holomorphically convex ?'
This is a generalization of the famous Uniformization Theorem for Riemann
Surfaces. We will discuss some applications of a positive solution of the
Sharafevich question, viz. A conjecture of Madhav Nori is true, and the
second homotopy group of a connected smooth projective surface is a free
abelian group.
We will also mention positive solutions for the Shafarevich question in
several interesting cases.
- Time:
- 3:30pm - 5:00pm
- Location:
- Room. 215
- Description:
- Commutative algebra seminars
Speaker: Hema Srinivasan
Affiliation: University of Missouri, Columbia, MO, USA
Date: 12 Nov. Monday 3.30-5.00, 15 Nov. Thursday 2.00-3.30
Venue: Room 215
Title: Mixed Multiplicities I and II
Abstract: Given a Noetherian Local Ring, with a maximal ideal $m$,
we will present the definition and existence of Mixed Multiplicities of
filtrations of $m-$ primary ideals. We will show that this mixed
multiplicity for general filtrations satisfies the standard theorems and
inequalities for mixed multiplicities for $m-$ primary ideals including the
Minkowski inequalities.
(This is joint work with Dale Cutkosky and Parangama Sarkar )
- Time:
- 5:00pm
- Location:
- Room. 215
- Description:
- Speaker: Cutkosky, Steven D.
Time & Date: 5pm Tuesday, November 13.
Venue: Room 215
Title: Poincare' series of divisors on surface singularities.
Abstract: We associate a Hilbert function to the exceptional components of a resolution of singularities of a surface singularity, and study its structure. We consider the question of when its associated Poincare' series is rational.
- Time:
- 2:30pm - 3:30pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
- Mathematics Colloquium
Speaker: Steven Dale Cutkosky, University of Mossouri
Date: Wednesday 14 November 2019
Time: 2.30-3.30
Venue: Ramanujan Hall
Title: Local Uniformization, Defect and Associated Graded Rings
Abstract: We discuss the problem of local uniformization (resolution of singularities along a valuation). We define the defect of an extension of valued fields and show that it is the only obstruction to local uniformization in positive characteristic. We explain how defect can be seen through lack of finite generation of associated graded rings along the valuation.
- Time:
- 2:00pm - 3:00pm
- Location:
- Room. 215
- Description:
- Commutative algebra seminars
Speaker: Hema Srinivasan
Affiliation: University of Missouri, Columbia, MO, USA
Date: 12 Nov. Monday 3.30-5.00, 15 Nov. Thursday 2.00-3.30
Venue: Room 215
Title: Mixed Multiplicities I and II
Abstract: Given a Noetherian Local Ring, with a maximal ideal $m$,
we will present the definition and existence of Mixed Multiplicities of
filtrations of $m-$ primary ideals. We will show that this mixed
multiplicity for general filtrations satisfies the standard theorems and
inequalities for mixed multiplicities for $m-$ primary ideals including the
Minkowski inequalities.
(This is joint work with Dale Cutkosky and Parangama Sarkar )
- Time:
- 4:00pm - 5:00pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
- Title: Control of wave equation.
Speaker: Debanjana Mitra,
Time: Friday, 16-11-18, 4p.m.-5p.m.
Venue: Ramanujan Hall, Department of Mathematics, IIT Bombay.
Abstract: In this talk, we will prove the observability inequality for
wave equation in the case of localized interior control.
Then the control of wave equation with variable coefficients will be
discussed.
- Time:
- 3:30pm
- Location:
- Room No. 215, Department of Mathematics
- Description:
- Commutative Algebra Seminar
Time: 19 Nov, Monday 3.30 pm
Venue: Room 215
Speaker: J. K. Verma
Title: Mixed multiplicities and the number of generators of ideals
Abstract: Using Minkowski inequality for mixed multiplicities of
ideals we derive an upper bound on the number of generators of
m-primary ideals in Cohen-Macaulay local rings. This upper bound
implies results of S.S. Abhyankar, E. Becker-D. Eisenbud-D. Rees,
I.S. Cohen, D. Rees and J. D. Sally.
- Time:
- 11:00am - 12:15pm
- Location:
- Room No 216 Department of Mathematics
- Description:
- PDE seminar on Control and homogenization:
Title: Control of wave equation.
Time: Thursday, 22-11-18, 11am-12:15pm.
Venue: Room 216
Speaker: Debanjana Mitra.
Abstract: In this talk, we will discuss the controllability of wave
equation with variable coefficients. The main objectives are to understand
the proof of the observability inequality and how the constants in the
inequality depend on the coefficients of the wave equation.
- Time:
- 11:30am - 12:30pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
- Commutative algebra seminar
Time: 22 Nov, Thursday, 11am-12noon.
Venue: Ramanujan Hall.
Speaker : Tony J. Puthenpurakal.
Title: On p_g ideals.
Abstract: Let $(A,\m)$ be an excellent normal domain of dimension two.
We define an $\m$-primary ideal $I$ to be a $p_g$-ideal if the Rees algebra
$A[It]$ is a \CM \ normal domain. When $A$ contains an algebraically
closed field $k \cong A/\m$ then Okuma, Watanabe and Yoshida proved that
$A$ has
$p_g$-ideals and furthermore product of two $p_g$-ideals is a $p_g$ ideal.
In this talk we show that if $A$ is an excellent normal domain of
dimension two containing a field $k \cong A/\m$ of characteristic zero
then also $A$ as $p_g$-ideals. Furthermore product of two $p_g$-ideals is
$p_g$.
- Time:
- 3:00pm - 4:00pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
- Analysis Seminar.
Time:Friday, 22 November, 3-4 pm.
Venue: Ramanujan Hall.
Speaker: Soumalya Joardar.
Title: Quantum Symmetry and graph C*-algebra.
Abstract: is attached.
- Time:
- 4:00pm - 5:00pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
- Mathematics Colloquium
Time: 4.00-5.00 pm, Wednesday, 21 November , 2018.
Venue: Ramanujan Hall
Speaker: Hema Srinivasan
Affiliation: University of Missouri, Columbia, MO, USA
Title: Resolutions of Semigroup Rings
Abstract: We consider the semigroup rings $S = k[t^{a_i}| 1\le i\le n]
\subset k[t]$ of embedding dimension $n$ over a field $k$. We write $S =
k[x_1, \ldots, x_n]/I_{a_1, \ldots, a_n}$ and explicitly construct the
minimal free resolutions of $S$ over $k[x_1, \ldots, x_n]$ when ${a_1,
\ldots, a_n}$ are special and derive formulae for the invariants such as
Betti Numbers, Cohen-Macaulay type, Frobenius numbers, Hilbert Series and
Regularity.
- Time:
- 5:30pm - 6:15pm
- Location:
- Room No 105 Department of Mathematical
- Description:
- CACAAG seminar.
Time: Thursday, 22 November, 5:30-6:15.
Venue: Room 105.
Speaker: Madhusudan Manjunath.
Title: Combinatorial Brill-Noether Theory, Stanley Theory,
Castelnuovo-Mumford Regularity.
Abstract: We discuss ongoing work where we relate Brill-Noether theory on
a finite graph to homological invariants of certain modules associated to
it. Our approach resembles Stanley's commutative algebraic approach to
enumeration of magic squares.
- Time:
- 11:00am - 11:45am
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
- Speaker: Prof. Sourav Pal
Title : Operator theory on the tetrablock
Date and Time : November, 11.00 am - 11.45 am
- Time:
- 11:45am - 12:30pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
- Speaker: Prof. Santanu Dey
Title : Maps between Hilbert C* modules
Date and Time : 26th November, 11.45 am - 12.30 pm.
- Time:
- 3:00pm
- Location:
- Room No. 216 Department of Mathematics
- Description:
- Date: 26 November
Time : 3 PM
Venue: Room 216
Title: Significance of Designs for Factorial Experiments and Web Resources in Agricultural Research
(Abstract currently not available)
Speaker: Dr. Rajender Parsad, FNAAS, FISAS
Principal Scientist (Agricultural Statistics)
ICAR-IASRI, Library Avenue, Pusa, New Delhi - 110 012, India
- Time:
- 12:00pm - 1:00pm
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
- Statistics Seminar
Date: 27/11/18
Time 12 noon-1 pm
Venue: Ramanujan Hall
Speaker: Professor Sat Gupta - Department of Mathematics and Statistics, UNC Greensboro
Title: Evaluating Performance of Mean Estimators of Sensitive Variables under Measurement Errors with Respect to Efficiency and Respondent Privacy
Abstract: In this study, our primary focus is on examining if using optional RRT models as opposed to non-optional RRT models for mean estimation of a sensitive variable when measurement errors are present, produces more efficient estimators. A unified measure of model efficiency and respondent privacy will be used in this comparison. The models discussed have data security implications as well.
- Time:
- 11:00am
- Location:
- Ramanujan Hall, Department of Mathematics
- Description:
- Speaker: Dr. Hina Gokhale, Former DG(HR), DRDO, New Delhi & VC, DIAT, Pune
Date & Time: 29th November, 11am
Venue: Ramanujan Hall
Title & Abstract: attached