CSUN Algebra, Number Theory, and Discrete Mathematics Seminar

at the Department of Mathematics, California State University, Northridge

Our Next Talk
    Tuesday, 21 November 2017    11:00 a.m-12:00 p.m.    Santa Susana Hall 108

    Imre Bárány
    Rényi Mathematical Institute, Hungarian Academy of Sciences
    and University College London

    Gershgorin's Disks

    Gershgorin's famous circle theorem states that all eigenvalues of a square matrix lie in certain disks (called Gershgorin disks) around the diagonal elements. Here we show that if the matrix entries are non-negative and an eigenvalue has geometric multiplicity at least two, then this eigenvalue lies in a smaller disk. The proof uses geometric rearrangement inequalities on sums of higher dimensional real vectors. Joint work with Jozsef Solymosi.

Directions: Santa Susana Hall is the building labeled SN in cell D2 of this map.
Room 108 is on the north edge of the northern courtyard (ground level) within the building.

If you are coming by car, the best visitor parking is either in lot B2 in cells B1-2,
or in lot G3 or structure G3 in cells F3 and G3 of the map.
See here for more parking information.

For more information, or to suggest a speaker, contact Daniel Katz
(email: [first name] [dot] [last name] [at] csun [dot] edu).

Schedule of Talks
Fall 2017
21 November 2017Gershgorin's DisksImre Bárány
Rényi Mathematical Institute, Hungarian Academy of Sciences
and University College London
08 November 2017Recognizing Weak Embeddings of GraphsCsaba D. Tóth
California State University, Northridge
13 September 2017Belyi maps and dynamicsIrene Bouw
Institute of Pure Mathematics, Ulm University
Spring 2017
12 April 2017Twisted differential maps and
differential algebraic independence
Wai Yan Pong
California State University, Dominguez Hills
11 April 2017Stable bundle/sheaf/complex
and Bogomolov Inequalities
Cristian Martinez
University of California, Santa Barbara
29 March 2017Book Crossing Numbers of Complete GraphsSilvia Fernández-Merchant
Calfornia State University, Northridge
Fall 2016
16 November 2016Peak Polynomials: Positivity
and Generalizations to Graphs
Mohamed Omar
Harvey Mudd College
31 October 2016Hasse principle and norm equationsEva Bayer
École Polytechnique Fédérale de Lausanne
Spring 2016
20 April 2016Generation Problems for Classical Algebraic GroupsSpencer Gerhardt
University of Southern California
24 February 2016Lattice spanners of low degreeAdrian Dumitrescu
University of Wisconsin-Milwaukee
Fall 2015
18 November 2015Spherical designs and latticesHiren Maharaj
Pomona College
28 October 2015Climbing the tower of covers to understand π1Katherine F. Stevenson
California State University, Northridge
Spring 2015
29 April 2015Solving quadratic equations over Q-barLenny Fukshansky
Claremont McKenna College
25 March 2015Children's drawings, flat refinements,
and geometric construction of number fields
with controlled ramification
Majid Hadian
18 March 2015Arc Diagrams, Flip distances,
and Hamiltonian triangulations
Michael Hoffmann
ETH Zürich
04 March 2015Lattices from function fields and lattices
from finite Abelian groups
Hiren Maharaj
Claremont McKenna College
25 February 2015Elementary Matrix Theory and Azumaya Algebras
in the (Dis)Service of Wireless Communication
Bharath A. Sethuraman
California State University, Northridge
Fall 2014
03 December 2014Unimodular congruence of the
Laplacian matrix for a graph
William Watkins
California State University, Northridge
12 November 2014Maximizing the number of copies of a patternBernardo Ábrego
California State University, Northridge
15 October 2014On Modular forms and their applicationsAnne-Maria Enrvall-Hytönen
University of Helsinki