15/06/23 | Seminario | 16:00 | 17:00 | 1201 Dal Passo | Cecilia Gonzalez Tokman | University of Queensland | Quenched limit laws and thermodynamic formalism for random dynamical systems
Non-autonomous or random dynamical systems (RDS) provide useful and flexible models to investigate systems whose evolution depends on external factors, such as noise and seasonal forcing. Modern developments on multiplicative ergodic theory and transfer operators allow us to get useful insights into the long-term behavior of these systems. In this talk, we will present results in this direction, including (quenched) limit theorems and thermodynamic formalism for a class of RDS. Our results will be illustrated with examples, including random open and closed intermittent maps and non-transitive systems. This talk is based on collaborations with J. Atnip, D. Dragicevic, G. Froyland and S. Vaienti.
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09/06/23 | Seminario | 16:00 | 17:00 | 1201 Dal Passo | Alessandro ZAMPINI | Università di Napoli "Federico II" |
Algebra & Representation Theory Seminar (ARTS)
"Derivation based differential calculus for a class of noncommutative spaces"
N.B.: partially supported by the MIUR Excellence Department Project MatMod@TOV awarded to the Department of Mathematics, University of Rome "Tor Vergata"
After a general introduction on differential calculi on noncommutative spaces, we equip a family of algebras whose noncommutativity is of Lie type with a derivation based differential calculus obtained, upon suitably using both inner and outer derivations, as a reduction of a redundant calculus over the Moyal four dimensional space. |
09/06/23 | Seminario | 14:30 | 15:30 | 1201 Dal Passo | Rosanna LAKING | Università di Verona |
Algebra & Representation Theory Seminar (ARTS)
"Cosilting complexes and asymptotic triangulations of the annulus"
N.B.: partially supported by the MIUR Excellence Department Project MatMod@TOV awarded to the Department of Mathematics, University of Rome "Tor Vergata"
In 2014 Baur and Dupont introduced the notion of an asymptotic triangulation. This is a combinatorial object arising naturally from the combinatorics of cluster algebras of type Ã. They showed that the set of all asymptotic triangulations has an interesting combinatorial structure: it is a poset and the edges of the Hasse graph can be obtained by flipping the asymptotic arcs. In this talk I will explain how this set parametrises certain 2-term complexes in derived category of a finite-dimensional algebra called a cluster-tilted algebra of type à and that the flip operation corresponds to a mutation operation.
This is joint work with L. Angeleri Hügel, K. Baur and F. Sentieri.
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07/06/23 | Seminario | 16:00 | 17:00 | 1201 Dal Passo | Claudio Dappiaggi | Univerità di Pavia |
Seminario di Algebre di Operatori
Stochastic Partial Differential Equations and Renormalization à la Epstein-Glaser
We present a novel framework for the study of a large class of nonlinear stochastic partial differential equations, which is inspired by the algebraic approach to quantum field theory. The main merit is that, by realizing random fields within a suitable algebra of functional-valued distributions, we are able to use specific techniques proper of microlocal analysis.These allow us to deal with renormalization using an Epstein-Glaser perspective, hence without resorting to any specific regularization scheme. As a concrete example we shall use this method to discuss the stochastic Phi^3_d model and we shall comment on its applicability to the stochastic nonlinear Schrödinger equation. |
30/05/23 | Seminario | 14:30 | 15:30 | 1201 Dal Passo | Eleonora Cinti | Università di Bologna | Seminario di Equazioni Differenziali
A regularity result for isoperimetric sets with density
In this talk, I will present a recent regularity result for isoperimetric sets with densities, under mild Holder regularity assumptions on the density functions. Our main Theorem improves some previous results and allows to reach the regularity class C^{1,frac{alpha}{2-alpha}} in any dimension. This is a joint work with L. Beck and C. Seis.
NB:This talk is part of the activity of the MIUR Excellence Department Project MATH@TOV CUP E83C23000330006 |
26/05/23 | Seminario | 16:00 | 17:00 | 1201 Dal Passo | Gleb NENASHEV | Brandeis University |
Algebra & Representation Theory Seminar (ARTS)
"Schubert Calculus and bosonic operators"
In this talk I will present a new point of view on Schubert polynomials via bosonic operators. In particular, we extend the definition of bosonic operators from the case of Schur polynomials to Schubert polynomials. More precisely, we work with back-stable Schubert polynomials and our operators act on the left weak Bruhat order. Furthermore, these operators with an extra condition give sufficiently enough linear equations for the structure of the cohomology ring of flag varieties.
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26/05/23 | Seminario | 14:30 | 15:30 | 1201 Dal Passo | Arun RAM | University of Melbourne |
Algebra & Representation Theory Seminar (ARTS)
"Boson-Fermion correspondence for Macdonald polynomials"
N.B.: partially supported by the MIUR Excellence Department Project MatMod@TOV awarded to the Department of Mathematics, University of Rome "Tor Vergata"
In its simplest form, this correspondence is the map from symmetric functions to skew-symmetric functions given by multiplication by the Weyl denominator (the Vandermonde determinant). A generalization produces the motivating shadow of “geometric Satake”, a diagram which contains the Satake isomorphism, the center of the affine Hecke algebra and the Casselman-Shalika formula. In a miracle that I wish I understood better, the whole diagram generalizes to the case of Macdonald polynomials and sends the bosonic Macdonald polynomial to the fermionic Macdonald polynomial. Does this suggest an “elliptic version" of geometric Langlands?
This talk is based upon arXiv2212.03312, joint with Laura Colmenarejo.
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25/05/23 | Seminario | 16:00 | 17:00 | 1201 Dal Passo | Mark Demers | Fairfield | Projective cones for dispersing billiards
We describe the recent construction of Birkhoff cones which are contracted by the action of transfer operators corresponding to dispersing billiard maps. The explicit contraction provided by this construction permits the study of statistical properties of a variety of sequential and open billiards. We will discuss some applications of this technique to chaotic scattering and the random Lorentz gas. This is joint work with C. Liverani. |
23/05/23 | Seminario | 14:30 | 15:30 | 1201 Dal Passo | Piotr Oprocha | AGH University of Krakow | On invariant sets with vanishing derivative and Cantor set dynamics (joint work with Silvere Gangloff)
Combinatorial graphs can serve as a nice tool for description of dynamical systems on Cantor set. A classical example of this type are Bratelli- Vershik diagrams. Recently, Shimomura, motivated by works of Akin, Glasner and Weiss, developed an alternative approach, which helps to describe dynamical systems on Cantor set by employing inverse limit of graphs. This approach provides a useful tool for description of dynamical systems on Cantor set.
As a particular application of the above approach we will present a method of construction of Cantor set $C$ with prescribed dynamics and its extension to interval maps with derivative zero on $C$. Starting motivation for this study is an old question whether invariant subset $Csubset [0,1]$ on which derivative of interval map $f$ vanishes must contain a periodic point. |
19/05/23 | Colloquium | 15:00 | 16:30 | 1201 Dal Passo | Eleonora Di Nezza | IMJ-PRG, Sorbonne Université | Evento "May 12: Celebrating Women in Maths" Ricci-flat spaces: one of the building blocks of the Universe
(Opening address by Barbara Nelli, University of L'Aquila)
Webpage (con link per lo streaming)
Note: This event is part of the activity of the MIUR Department of Excellence Project MatMod@TOV.
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