Colloquium

Place: Room 614 in the Education & Sciences Building Time: 14:00                                                    Abstract: Bounded harmonic functions on groups are closely related to random walks on groups. It has long been known that all virtually nilpotent groups are “Choquet-Deny groups”: these groups cannot support…
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  Place: Room 614 in the Education & Sciences Building Time: 14:00   Abstract:   Being fractionally Calabi-Yau is a periodicity property of triangulated categories introduced by Kontsevich more than 20 years ago. It is quite rare that a finite-dimensional algebra has…
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  Place: Room 614 in the Education & Sciences Building Time: 14:00   Abstract: A predictive sequence is a subset P of {n<0} such that for any finite valued zero entropy stationary ergodic process {X_j} the random variable X_0 is a function…
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Place: Room 614 in the Education & Sciences Building Time: 14:00   Abstract:   Given a set S of positive measure on the unit circle, a set of integers K is an interpolation set (IS) for S if for any data {c(k)}…
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Place: Room 614 in the Education & Sciences Building Time: 14:00 Abstract: Open Gromov-Witten (OGW) invariants should count pseudoholomorphic maps from Riemann surfaces with boundary to a symplectic manifold, with boundary conditions and various constraints on boundary and interior marked…
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Place: Room 614 in the Education & Sciences Building Time: 14:00 We discuss how something remarkably similar to Hall’s marriage theorem appears naturally in context of a conjecture of Grothendieck in algebraic geometry, and how this is useful to prove…
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Given a family of sets, a partial choice function chooses an element from some of them. The range of the function is then called a “rainbow set” (the “colors” being the sets). There are two types of conditions that are…
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Place: Room 614 in the Education & Sciences Building Time: 14:00   Abstract: A king-non-attacking permutation is a permutation $\pi \in S_n$ such that $|\pi(i)-\pi(i-1)|\neq 1$ for each $i \in \{2,\dots,n\}$. We investigate the structure of the poset of these permutations under…
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  Place: Room 614 in the Education & Sciences Building Time: 14:00   Abstract:   Hyperbolic manifolds play an important role in geometry and topology, and in the 1980s Gromov introduced a notion of large-scale negative curvature that is strong enough to…
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Place: Room 614 in the Education & Sciences Building Time: 14:00 Abstract: In this talk I will start by a gentle introduction of non-singular actions and ergodic theory. After that we will discuss some recent progress, which culminated in a…
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