Motivic degree zero Donaldson - Thomas invariants
APA
Bryan, J. (2010). Motivic degree zero Donaldson - Thomas invariants. Perimeter Institute. https://pirsa.org/10050038
MLA
Bryan, Jim. Motivic degree zero Donaldson - Thomas invariants. Perimeter Institute, May. 08, 2010, https://pirsa.org/10050038
BibTex
@misc{ pirsa_PIRSA:10050038, doi = {10.48660/10050038}, url = {https://pirsa.org/10050038}, author = {Bryan, Jim}, keywords = {}, language = {en}, title = {Motivic degree zero Donaldson - Thomas invariants}, publisher = {Perimeter Institute}, year = {2010}, month = {may}, note = {PIRSA:10050038 see, \url{https://pirsa.org}} }
University of British Columbia
Collection
Talk Type
Abstract
The Hilbert scheme X[n] of n points on variety X parameterizes length n, zero dimensional subschemes of X. When X is a smooth surface, X[n] is also smooth and a beautiful formula for its motive was determined by Gottsche. When X is a threefold, X[n] is in general singular, of the wrong dimension, and reducible. However if X is a smooth Calabi-Yau threefold, X[n] has a canonical virtual motive --- a motification of the degree zero Donaldson-Thomas invariants. We give a formula analogous to Gottsche's for the virtual motive of X[n]. The key computation gives a q-refinement of the classical formula of MacMahon which counts 3D partitions.