Jason Bell, Department of Pure Mathematics, University of Waterloo
"Last talk of the seminar"
MC 5479
Farida Shahata, Department of Pure Mathematics, University of Waterloo
"More projective geometry"
Projective schemes make a comeback! Following our previous discussion on closed immersions and closed subschemes, the next natural step is to study closed embeddings of projective schemes.
As for affine schemes, we will see that a surjection of graded rings induces a closed embedding of projective schemes. Conversely, every closed subscheme of a projective scheme arises from a graded ideal, hence, is projective itself.
Seda Albayrak, Department of Pure Mathematics, University of Waterloo
"Finite Automata and Transcendence Theory"
Barbara Csima, Department of Pure Mathematics, University of Waterloo
"Every $\Delta^0_2$ degree is a strong degree of categoricity"
We sketch the proof that every $\Delta^0_2$ degree is a strong degree of categoricity. This is joint work with Keng Meng Ng.
MC 5417
Ross Willard, Department of Pure Mathematics, University of Waterloo
"Uncountable SIs in residually small varieties in a countable signature"
McKenzie Wang, McMaster University
"Examples of Ancient Flows on Bundles"
I will report on joint work with Peng Lu on constructing ancient flows on a large class of compact bundles. These examples are of type I and include both collapsed and non-collapsed cases. In special cases, we can also describe the forwards limit of these ancient flow. As a bonus of this work, we also obtain examples of such ancient flows for pseudo-Riemannian metrics.
MC 5403
Mahya Ghandehari, University of Delaware
"Characterizing the Sobolev wavefront set via continuous wavelet transforms"
Hanfeng Li, SUNY Buffalo
"Mean dimension and von Neumann-Lueck rank"
Mean dimension is an invariant in topological dynamics, while von Neumann-Lueck rank is an invariant in L2-invariants theory, closely related to the L2-Betti numbers. Based on joint work with Bingbing Liang, I will discuss how these two invariants are related to each other.
MC 5501
Stan Xiao, University of Oxford
"Binary quartic forms with vanishing J-invariant and the subvariety problem"
Ross Willard, Department of Pure Mathematics, University of Waterloo
"Uncountable SIs in residually small varieties in a countable signature, part II"
Continuing the proof of "the theorem" of McKenzie and Shelah, I will prove some properties of pp-1-types in subdirectly irreducible algebras whose monolith is (0,1)-generated.
MC 5479