Cotygodniowe seminarium badawcze
Organizatorzy
- prof. dr hab. Rafał Latała
Informacje
czwartki, 12:15 , sala: 3160Strona domowa
http://lists.mimuw.edu.pl/listinfo/sem-rpLista referatów
-
12 grudnia 2024 12:15
Michał Strzelecki (Uniwersytet Warszawski)
Lower bounds for weak-type constants of some operators (Lower bounds for weak-type constants of some operators)
In the talk I shall present a counterexample to a conjecture of Gill about the exact value of the weak-type (1,1) constant of some Hardy-type operators (which arise when one restricts the Beurling-Ahlfors transform to …
-
28 listopada 2024 12:15
Maciej Rzeszut
Gaussian approximation of B-splines in Schwartz seminorms (Gaussian approximation of B-splines in Schwartz seminorms)
We consider sections of the $n-1$ dimensional simplex $\Delta_{n-1}= \left\{y\in\R_+^n: \sum_k y_k= 1\right\}$ by hyperplanes $\sum x_k y_k=t$, for a vector $x$ satisfying the assumptions of Berry-Esseen theorem, i.e. $\sum x_k=0,\sum x_k^2=1$ and $m^3:=\sum\left|x_k\right|^3$ is …
-
21 listopada 2024 12:15
Dominik Kutek (University of Warsaw)
Bregman variation of semimartingales (Bregman variation of semimartingales)
The quadratic variation is a key concept in stochastic calculus, with widespread applications in mathematics and economy. The talk will be about a similar, but more general concept, the Bregman variation (or phi-variation) of semimartingales. …
-
14 listopada 2024 12:15
Peter Pivovarov (Univeristy of Missouri)
Stochastic methods in dual Brunn--Minkowski theory (Stochastic methods in dual Brunn--Minkowski theory)
The surface area of a convex body can be obtained as an average of the areas of its shadows (1-codimensional projections). In turn, the surface area is just one of the k-quermassintegrals of a convex …
-
7 listopada 2024 12:15
Tomasz Tkocz
Convexity properties of sections and Rademacher sums (Convexity properties of sections and Rademacher sums)
I shall discuss certain convexity properties of hyperplane sections of 1-symmetric convex bodies as well as Rademacher sums, which are motivated by chessboard cutting problems and the logarithmic Brunn-Minkowski problem.
-
31 października 2024 12:15
Witold Bednorz (Uniwersytet Warszawski)
Some consequences of the new approach to positive stochastic processes. (Some consequences of the new approach to positive stochastic processes.)
In my talk I will explain our idea of an equivalent characterization of the supremum expectation of positive stochastic processes. Some consequences will be discussed, in particular for the Sudakov minoration for canonical processes based …
-
17 października 2024 12:15
Rafał Latała (Uniwersytet Warszawski)
Operator \ell_p to \ell_q norms of structured Gaussian matrices (Operator \ell_p to \ell_q norms of structured Gaussian matrices)
We discuss two-sided bounds for operator \ell_p to \ell_q norms of structured Gaussian matrices in the case 1\le p\le 2\le q\leq \infty. Guédon, Hinrichs, Litvak and Prochno conjectured that an easy lower bound for the …
-
10 października 2024 12:15
Adam Osękowski (Uniwersyte Warszawski)
Fefferman's inequality for analytic functions (Nierówność Feffermana dla funkcji analitycznych)
Klasyczny wynik analizy harmonicznej głosi, iż przestrzenią dualną do przestrzeni Hardy'ego H^1 na okręgu jednostkowym T jest analityczna przestrzeń BMO(T). Celem odczytu będzie wyznaczenie optymalnej stałej w nierówności Feffermana, stanowiącej połowę powyższej charakteryzacji. Dowód będzie …
-
6 czerwca 2024 12:15
Kamil Szpojankowski (Politechnika Warszawska)
Warunkowe wartości oczekiwane dla wolnych zmiennych i związki z macierzami losowymi
Badania w wolnej probabilistyce od końca lat 90 skupiają się na narzędziach pochodzących z tzw. subordynacji wolnego splotu udowodnionej przez Biane'a, która mówi, że dla $X,Y$ wolnych $E((z-X-Y)^{-1}|X)=(\omega(z)-X)^{-1}. Do tej pory nieznane były narzędzia pozwalające …
-
23 maja 2024 12:15
Paweł Hitczenko (Drexel University)
Asymptotics of a class of polynomial recurrences
We will consider sequences of polynomials defined by a recursion involving these polynomials and their first order derivatives. Recurrences like that are common in combinatorial probability and have been used and analyzed throughout the years. …
-
16 maja 2024 12:15
Soumik Dutta (University of Warsaw)
On Edge Collapse of Random Simplicial Complexes
Edge collapse, introduced in [Boissonnat, Pritam. SoCG 2020], is a process to reduce the size of a simplicial complex while preserving its homology. We study the effect of edge collapse on the Erdos-Renyi random clique …
-
9 maja 2024 12:15
Witold Bednorz (University of Warsaw)
Concentration of truncated variation for fractional Brownian motion
The talk will be about some new result that concerns bounding variation for fBM. In particular, I show some technique, due to Picard, which makes it possible to introduce some independence in studying similar questions. …
-
18 kwietnia 2024 12:15
Piotr Godlewski
Gram-Schmidt Walk algorithm and consequences for Komlós conjecture
Komlós conjecture states that minimal discrepancy of a set of vectors in R^d is bounded from above by a universal constant. I will present, by using a method called Gram-Schmidt Walk, how the best known …
-
11 kwietnia 2024 12:15
Daniel Murawski (Uniwersytet Warszawski)
Comparing moments of real log-concave random variables.
Log-concave random variables play an important role in probability theory. Moment comparison inequalities of the form ∥X∥_p ≤ C_{p,q}∥X∥_q are particularly useful in concentration of measure and convex geometry. In this talk, I will present …
-
4 kwietnia 2024 12:15
Rafał Latała (University of Warsaw)
Operator norm of Rademacher random matrices
We will discuss two-sided bounds for the mean value of the operator norm of random matrices with weighted Rademacher entries. We will recall a conjecture (formulated together with Witold Świątkowski) and show that it holds …