Geometry and Topology Seminar
Ben Sibley, Simons Center, Stony Brook University
"Limits and bubbling sets for the Yang-Mills flow on Kaehler manifolds"
Ben Sibley, Simons Center, Stony Brook University
"Limits and bubbling sets for the Yang-Mills flow on Kaehler manifolds"
Jaspar Wiart, Department of Pure Mathematics, University of Waterloo
"The Jacobson Radical of Certain Semicrossed Products"
We study the Jacobson radical of the semicrossed product $A\times_\alpha P$ when $A$ is a simple C*-algebra and $P$ is either a subsemigroup of an abelian group or a free semigroup. A full characterization is obtained for a large subset of these semicrossed products and we apply our results to a number of examples.
MC 5417
Brett Nasserden, Department of Pure Mathematics, University of Waterloo
"Matroidal flips and related ideas/constructions"
Jonny Stephenson, Department of Pure Mathematics, University of Waterloo
"Co-spectra"
The co-spectrum of a structure is the family of sets coded by the structure. This is a measure of how well we can encode information in the structure. We will see that every countable ideal in the e-degrees is the co-spectrum of a structure, and give a generalization of Richter's result on c.e.-minimal pairs.
MC 5403
Manousos Maridakis, Rutgers University
"Lojasiewicz-Simon gradient inequalities with applications to Yang-Mills pairs and Harmonic maps"
Teng Fei, Columbia University
"A construction of infinitely many solutions to the Strominger system"
Panagiotis Gianniotis, Department of Pure Mathematics, University of Waterloo
"A heat flow for special metrics II"
This is the second talk on the paper of Weiss and Witt 'A heat flow on special metrics'. In this talk, we will implement DeTurck's trick to the Dirichlet flow and show that the resulting equation is parabolic. Then we will focus on the issue of stability around the set of critical points for the Dirichlet functional.
MC 5479
Jonny Stephenson, Department of Pure Mathematics, University of Waterloo
"Degree Spectra"
Last week we saw that every countable ideal in the enumeration degrees is the co-spectrum of some structure. Now we will consider what sets of degrees are spectra of structures. We will see that the situation is quite different, and that there are a number of classes which cannot be the spectrum of any structure. In particular, no nontrivial countable union of enumeration upper cones can be the spectrum of any structure.
MC 5403
Diana Castaneda Santos, Department of Pure Mathematics, University of Waterloo
"The end of the Quasiseparated talk and the beginning of a new age"
We will finish our discussion on topological properties of schemes. We will finally define quasiseparated schemes and see how they are related with quasicompact schemes. Additionally, we will start section 5.3. talking about the communication lemma, which is a convenient way to study properties on schemes by looking at properties on any affine open covering.
MC 5479
Shubham Dwivedi, Department of Pure Mathematics, University of Waterloo
"Simons' Inequality and consequences"
We will prove the Simons' Inequality which is satisfied by the laplacian of the normed square of the second fundamental form of any minimal hypersurface in $\mathbb{R}^n$. We will then prove various consequences of the inequality, including results of Choi and Schoen, Hopf and that of Schoen/Leon Simon/Yau.
MC 5479