Institut de Mathématiques de Marseille, UMR 7373




Rechercher


Accueil >

22 juin 2018: 4 événements

Séminaire

  • Séminaire Probabilités et Statistique

    Vendredi 22 juin 09:30-10:30 - Leonardo ROLLA - University of Buenos Aires, New York University Shanghai

    Absorbing-State Phase Transitions

    Résumé : Modern statistical mechanics offers a large class of driven-dissipative stochastic systems that naturally evolve to a critical state, of which Activated Random Walks are perhaps the best example. The main pursuit in this field is to show universality of critical parameters, describe the critical behavior, the scaling relations and critical exponents of such systems, and the connection between driven-dissipative dynamics and conservative dynamics in infinite space.
    This problem was stuck for more than a decade, then it saw significant partial progress about 9 years ago, and got stuck again. In this talk we will report on exciting progress made in the last 4 years, thanks to the contributions of Basu, Cabezas, Ganguly, Hoffman, Sidoravicius, Stauffer, Taggi, Teixeira, Tournier, Zindy, and myself. We will also discuss some of the many open problems.

    JPEG - 9 ko
    Leonardo ROLLA

    Lieu : CMI, salle de séminaire R164 (1er étage) - I2M - Château-Gombert
    39 rue Frédéric Joliot-Curie
    13453 MARSEILLE cedex 13

    Exporter cet événement
    Document(s) associé(s) :

    En savoir plus : Séminaire Probabilités et Statistique

  • Séminaire Teich

    Vendredi 22 juin 11:00-12:00 - Natalia A. Viana BEDOYA - I2M, Aix-Marseille Université

    Séminaire Teich (TBA)

    Résumé : TBA



    Lieu : FRUMAM - Aix-Marseille Université - Site St Charles
    3, place Victor Hugo - case 39
    13331 MARSEILLE Cedex 03

    Exporter cet événement

En savoir plus : Séminaire Teich

  • Séminaire Signal et Apprentissage

    Vendredi 22 juin 14:00-15:00 - Hugo RAGUET - CEA-DER, Cadarache

    Cut-pursuit algorithm for regularizing nonsmooth functionals with graph total variation

    Résumé : I will present an extension of the cut-pursuit algorithm, introduced by Landrieu and Obozinski (2017), to the _graph total-variation_ regularization of functions with a separable nondifferentiable part.
    We propose a modified algorithmic scheme as well as adapted proofs of convergence. We also present a heuristic approach for handling the cases in which the values associated to each vertex of the graph are multidimensional.
    The performance of our algorithm, which we demonstrate on difficult, ill-conditioned large-scale inverse and learning problems, is such that it may in practice extend the scope of application of the total-variation regularization.
    -
    This is a joint work with Loïc Landrieu (IGN, LaSTIG MATIS).
    -
    Landrieu, L. and Obozinski, G. "Cut pursuit : Fast algorithms to learn piecewise
    constant functions on general weighted graphs
    ". SIAM Journal on Imaging
    Sciences, 10(4):1724–1766, 2017.



    JPEG - 10 ko
    Hugo RAGUET

    Lieu : CMI, salle de séminaire R164 (1er étage) - I2M - Château-Gombert
    39 rue Frédéric Joliot-Curie
    13453 MARSEILLE cedex 13

    Exporter cet événement
    Document(s) associé(s) :

    En savoir plus : Séminaire Signal et Apprentissage

  • Colloquium de Mathématiques de Marseille

    Vendredi 22 juin 16:00-17:00 - Peter BOUWKNEGT - Australian National University, Canberra

    Dualities in Mathematics and Physics

    Résumé : In this talk I will review some geometric analogues of the Fourier transform, which arise in String Theory under the name of ‘dualities’. In particular, I will discuss global aspects of T-duality and mention some recent generalisations. T-duality has important applications in different areas of mathematics, such as in differential geometry, algebraic topology, operator algebras, noncommutative geometry, as well as in physics.
    This is a talk aimed at non-specialists and will include many examples.



    JPEG - 4.6 ko
    Peter BOUWKNEGT

    Lieu : FRUMAM, 2e étage - Aix-Marseille Université - Site St Charles
    3, place Victor Hugo - case 39
    13331 MARSEILLE Cedex 03

    Exporter cet événement
    Document(s) associé(s) :

    En savoir plus : Colloquium de Mathématiques de Marseille

  • 22 juin 2018: 2 événements

    Manifestation scientifique

    En savoir plus : Agenda ERC IChaos