UMass Amherst
Department of Mathematics and Statistics
Directory  Courses  Undergraduate  Graduate  Research  Seminars  Calendar  Contacts  Resources  Donate  
Faculty  Graduate Students  Staff  Emeritus Faculty  

Tom Braden, Associate Professor
Personal Webpage
Office LGRT 1240
Phone (413) 545-1732
Fax (413) 545-1801
Email braden <at> math.umass.edu
Mailing Address
Department of Mathematics and Statistics
Lederle Graduate Research Tower
University of Massachusetts
Amherst, MA 01003-9305
Office Hours: Tuesdays 2-3, Thursdays 3-4
Courses  
Fundamental Concepts of Mathematics and 1 credit co-seminar
Math 300.1 (MWF 10:10 - 11:00 am, LGRT 113)
Affine and Projective Geometry
Math 461 (MWF 1:25 - 2:15 pm, LGRT 119)
Education  
Ph.D.Massachusetts Institute of Technology, 1995
Cambridge University (part III of mathematics tripos), 1991
B.A.University of Chicago, 1990
Research Interests: Topology and singularities of algebraic varieties; intersection (co)homology and perverse sheaves; Schubert varieties, toric varieties, and their generalizations; connections to combinatorics and representation theory.
Prof. Braden studies the topology of singular algebraic varieties, especially toric varieties and Schubert varieties. He uses invariants like intersection cohomology to extract information about the combinatorial structure of polytopes and Coxeter groups from these varieties. A major theme in his work is lifting or "categorifying" relations and inequalities among combinatorial invariants by showing that they arise from canonical relations among topological invariants; an inequality might arise from showing that a map of cohomology groups is an injection, for instance. These relations are studied by working equivariantly, using the symmetries imposed by large groups acting on the varieties.
Selected Publications
T. Braden and N. Proudfoot, The hypertoric intersection cohomology ring, Invent. Math. 177 (2009), no. 2, 337--379.
T. Braden and V. Lunts, Equivariant-constructible Koszul duality for dual toric varieties, Adv. Math. 201 (2006), no. 2, 408-453.
T. Braden and R. MacPherson, From moment graphs to intersection cohomology, Math. Ann. 321 (2001), no. 3, 533-551.
T. Braden and R. MacPherson, Intersection homology and a conjecture of Kalai, Comment. Math. Helv. 74 (1999), no. 3, 442--455.



Return to front