Seminario de Probabilidad

En este seminario se expone trabajos recientes en teoría de probabilidades.
2017-04-25
15:30hrs.
Christophe Profeta. Universite D'evry Val D'essonne
Stable Langevin Model With Diffusive-Reflective Boundary Conditions. 
Sala 5, Facultad de matemáticas, Campus San Joaquín. PUC.
Abstract:

Resumen : We consider a one-dimensional stable Langevin process confined in the upper half-plane and submitted to a diffusive-reflective boundary condition whenever the particle position hits 0. We show that different regimes appear according to the value of the chosen parameters. We then use this study to construct the law of a (free) stable Langevin process conditioned to stay positive, thus extending earlier works on the integrated Brownian motion. Such construction finally enables us to improve some recent persistence probability estimates. This is a joint work with Jean-François Jabir.

http://nm.cmm.uchile.cl/seminarios/
2016-11-24
16:30 hrs.hrs.
Karl Liechty . Depaul
Propagation Of Critical Behavior For Unitary Invariant Plus Gue Random Matrices
Sala John Von Neumann, 7mo piso, CMM.
Abstract:
 
 It is a well known and celebrated fact that the eigenvalues of random Hermitian matrices from a unitary invariant ensemble form a determinantal point process with correlation kernel given in terms of a system of orthogonal polynomials on the real line. It is a much more recent result that the eigenvalues of the sum of such a random matrix with a matrix from the Gaussian unitary ensemble (GUE) also forms a determinantal point process, with the kernel given in terms of the Weierstrass transform of the original kernel. I'll talk about the case in which the limiting distribution of eigenvalues is critical in the sense that there is a non-generic scaling limit for the correlation kernel, and discuss the effect of a Gaussian perturbation on the limiting critical kernel. This is joint work with Tom Claeys, Arno Kuijlaars, and Dong Wang.
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http://nm.cmm.uchile.cl/seminarios/
2016-11-14
16:30hrs.
Bernardo Nunes Borges de Lima . Ufmg
Embedding Binary Sequences Into Bernoulli Site Percolation On Z3
Sala Jacques L. Lions, CMM, Universidad de Chile 
Abstract:
 
 
 We investigate the problem of embedding infinite binary sequences into Bernoulli site percolation on Zd with parameter p. In 1995, I. Benjamini and H. Kesten proved that, for d≥10 and p=1/2, all sequences can be embedded, almost surely. They conjectured that the same should hold for d≥3. We consider d≥3 and p∈(pc(d),1−pc(d)), where pc(d)<1/2 is the critical threshold for site percolation on Zd. We show that there exists an integer M=M(p), such that, a.s., every binary sequence, for which every run of consecutive {0s} or {1s} contains at least M digits, can be embedded. Joint work with M. Hilário (UFMG), P. Nolin (ETH) and V. Sidoravicius (IMPA)

www.nucleoproba.cl
2016-08-10
Christophe Profeta. Université D’Evry Val D’Essonn
Tbd
Sala 2 - Facultad de Matemáticas a las 16:30 Hrs.
2016-06-12
Ioannis Papageorgiou. UBA
The Log-Sobolev Inequality For Unbounded Spin Systems On The Lattice.
Sala 2 - facultad de Matemáticas a las 16:30 Hrs.
2016-06-12
Aurelia Deshayes. UBA
Scaling Limit Of Subcritical Contact Process
Sala 2 - Facultad de Matemáticas a las 16:30 Hrs.
2016-06-05
Chi Nguyen. UBA
Tbd
Sala 2 - Faculad de Matemáticas a las 16:30 Hrs.
2016-05-15
Santiago Saglietti. P. Universidad Católica de Chile
The Kesten-Stigum Theorem In L^2 For Abbmd
CMM Sala por confirmar a las 16:30 Hrs.
2016-05-09
Mauricio Duarte. UBA
Gravitation Versus Brownian Motion
Sala 2, Facultad de Matemáticas a las 16:30 Hrs.
2016-04-25
Julián Martinez. UBA
Hydrodynamic Limit For Branching Brownian Particles With Spatial Selection And The Kpp Equation.
Sala 2 de la Facultad de Matemáticas a las 16:30 Hrs.
2016-04-02
Mauricio Duarte. Uab
Gravitation Versus Brownian Motion
Sala 2, Facultad de matemáticas, Campus San Joaquín, Pontificia Universidad Católica de Chile.
2015-11-20
Gregorio Moreno. P. Universidad Católica de Chile
Brox Diffusion And Sinai´s Walk In The Intermediate Regime
Sala 2, Facultad de Matemáticas a las 17:30 Hrs.
2015-10-06
Manuel González. Universidade de Sao Paulo
A Ferromagnetic Ising Model With Periodic External Field.
Sala 5, Facultad de matemáticas, PUC Chile, Campus San Joaquín. a las 17:00 Hrs.
2015-04-25
Julián Martinez. UBA
Hydrodynamic Limit For Branching Brownian Particles With Spatial Selection And The Kpp Equation.
Sala 2 Facultad de Matemáticas - 16:30 Hrs.
2015-01-13
Daniel Ahlberg. Impa
Quenched Voronoi Percolation
Sala Multimedia del Centro de Modelamiento Matemático de la Universidad de Chile, en Beauchef 851, Torre Norte, 6° piso (acceso por el 7° piso)
2014-07-23
Gia Bao Nguyen. Cmm-Universidad de Chile
Interacting Partially Directed Self Avoiding Walk
Sala 2 Facultad de Matemáticas 16:30 Hrs.
2014-03-18
Achilleas Tzioufas. Buenos Aires
On The Clt For The Extremal Particles Of Supercritical Contact Processes
Sala 1 de la Facultad de Matemáticas
Abstract:
Abstract: The talk is concerned with the growth of symmetric one-dimensional contact processes on survival. By means of a new approach that relies on stochastic domination arguments and leverages from symmetry to employ well-known facts, we show the existence of random regenerative space-time points on the trajectory of their extremal particles.

2013-12-11
Daniel Remenik. Universidad de Chile
Exact Formulas For Random Growth Off a Flat Interface
Sala 1 Facultad de Matemáticas - 17:00 Hrs.
Abstract:
Resumen: We will describe formulas for the asymmetric simple exclusion process (ASEP) starting from half-flat and flat initial data. These formulas express the exponential moments of the height function associated with ASEP in terms of multiple contour integrals. In the flat case this allows to express a certain generating function for the model as a Fredholm Pfaffian. We will explain also how these formulas can be used to provide formal derivations of the conjectured limiting fluctuations of these models. This is joint work with Janosch Ortmann and Jeremy Quastel.
Dia: miercoles 11 de diciembre 2013
Hora: 17:00


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2013-11-20
Milton Jara. Impa, Rio de Janeiro
Anomalous Heat Conduction And The Fractional Laplacian
Sala 2 (víctor Ochsenius) - Facultad de Matemáticas - 17:00 Hrs.
Abstract:
Resumen: For a model of stochastically perturbed harmonic oscillators, we show that energy fluctuations are governed by a fractional heat equation. The method of proof relies on a novel extension problem, reminiscent of the Caffarelli-Silvestre extension problem, which is of independent interest. Joint work with Cedric Brnardin (Nice) and Patricia Gonçalves (PUC-Rio)
2013-09-24
Elodie Bouchet. Universite de Lyon
Sub-Ballistic Random Walk In Dirichlet Environment
Sala 1 - Facultad de Matemáticas UC
Abstract:
Resumen: We consider random walks in Dirichlet environment on Z^d, for d >= 3, in the sub-ballistic case. We associate to any parameter (__1 , . . . , __2d ) of the Dirichlet law a time-change for the walk, and we prove that the continuous-time time-changed walk has an absolutely continuous invariant probability measure for the environment viewed from the particle. This allows to characterize directional transience for the initial RWDE. It solves as a corollary the problem of Kalikow’s 0_1 law in the Dirichlet case in any dimension.