Seminars

18-01-2017 11:15
, C-11 PWr (Wydział Matematyki), sala 2.11
Mixed norm estimates for generalized radial spherical means
Adam Nowak (IM PAN)
19-10-2017 14:15
, 603
Large deviations for branching process in random environment
Piotr Dyszewski (Uniwersytet Wrocławski)
We will consider a version of Galton-Watson process called the branching process in random environment, describing a population growth where the individuals reproduce independently of each other with the reproduction law randomly picked at each generation. We will focus on large deviations for the process in question. If time allows we will investigate the corresponding first passage time.  The talk is based on a joint work with Dariusz Buraczewski available at https://arxiv.org/abs/1706.03874
19-10-2017 10:00
, 604
Distributions on non-symmetric position operators on Weakly Monotone Fock Space.
Maria Elena Griseta (University of Bari Aldo Moro)
In this talk we investigate the distributions for sums of random variables $x_i={a_i}^{-}+{a_i}^{†}+\lambda {a_i}^0$, where ${a_i}^{-}$, ${a_i}^{†}$ and ${a_i}^0$ denote respectively annihilation, creation and conservation operators on the Weakly Monotone Fock Space and $\lambda\in \mathbb{R}$. We start considering sum of position operators (case $\lambda=0$): after obtaining a recursive formula for the moments \[ \mu_{m,n} := \omega_{\Omega}\bigg(\bigg(\sum_{k=1}^{m}(A_{k}+A_{k}^{†})\bigg)^{2n}\bigg), \] where $\Omega=1\oplus 0\oplus 0 \oplus 0\oplus \ldots$ is the vacuum vector and $\omega_{\Omega}(\cdot)=\left\langle \Omega,\cdot\Omega\right\rangle$ is the vacuum expectation, we calculate the Cauchy Transform of the distribution measure and the density for $m=2$. Finally we compute the distribution of a single random variable $x_i$ with respect to the vacuum state for the general case $\lambda\neq 0$.
16-10-2017 14:15
, 604
Higher rank hyperbolicity in spaces of nonpositive curvature
Urs Lang (ETH Zurich)

The large scale geometry of Gromov hyperbolic metric spaces exhibits many distinctive features, such as the stability of quasi-geodesics (the Morse Lemma), the linear isoperimetric filling inequality for 1–cycles, the visibility property, and the homeomorphism between visual boundaries induced by a quasi-isometry. In this talk, I will describe a number of closely analogous results for spaces of rank n > 1 in an asymptotic sense, under some weak assumptions reminiscent of nonpositive curvature. A central role is played by a suitable class of n–dimensional surfaces of polynomial growth of order n, which serve as a substitute for quasi-geodesics.

23-10-2017 15:15
, 603
Półliniowe równania eliptyczne z operatorami Dirichleta i miarami borelowskimi
Tomasz Klimsiak (Uniwersytet Mikołaja Kopernika)
04-10-2017 16:15
, 604
Virtually free groups and Galois actions
Piotr Kowalski (Uniwersytet Wrocławski)

I will talk about joint work with Özlem Beyarslan (the last version of our paper is available here: http://www.math.uni.wroc.pl/~pkowa/mojeprace/vfree4.pdf). We showed that for a finitely generated virtually free group G, the theory of actions of G on fields has a model companion, which we call G-TCF. We also gave an algebraic condition on G, which is equivalent to simplicity of the theory G-TCF. Recently, we learnt from Ehud Hrushovski an argument showing that if the group Z × Z embeds into G, then the theory of G-actions on fields does NOT have model companion. I will present this argument as well.

26-10-2017 12:15
, 602
Sojourns of Gaussian processes with trend.
Krzysztof Dębicki (Uniwersytet Wrocławski)
W wystąpieniu przedstawione zostanie nowe podejście do badania zagadnień związanych z analizą czasu przebywania nad barierą przez niescentrowane procesy gaussowskie. Wystąpienie oparte jest o wspólne badania z E. Hashorvą, P. Liu, Z. Michną.
05-06-2017 16:15
, 604
Słaba selekcja generuje porządek.
Krzysztof Omijlanowski
26-10-2017 12:15
, 606
Uporządkowanie rozkładów czasu pracy systemów z wykorzystaniem własności mieszanek
Maria Kamińska-Zabierowska (Wyższa Szkoła Oficerska Wojsk Lądowych)
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