• Apr 23 2013

    WITS Node Seminar: Prof Martin Porrmann (UKZN)


    The National Institute for Theoretical Physics, and the Centre for Theoretical Physics, School of Physics, would like to invite to its coming talk in the theory seminar series, entitled:

    "A Universal Concept for Particles in Local Quantum Physics"

    to be presented by Prof. Martin Porrmann (UKZN)

    Abstract: The notion of Wigner particles is attached to irreducible unitary representations of the Poincare group, characterised by two parameters m and s interpreted as mass and spin, respectively. However, the Lorentz symmetry is broken in theories with long-range interactions like electrodynamics, rendering this approach inapplicable (the so-called infraparticle problem). A unified treatment of both Wigner particles and infraparticles via the concept of particle weights can be developed within the framework of local quantum physics. Particle weights arise as temporal limits of physical states in the vacuum sector and describe the asymptotic particle content. I present an introduction to their definition and characteristic properties as well as a sketch of their disintegration into pure components. These pure particle weights allow for the mathematically consistent definition of mass and spin in both the Wigner and infraparticle case.

    Date: Tuesday, 23rd April 2013
    Venue: Frank Nabarro Lecture Theatre P216
    Time: 13.20 - 14.10

    For more information please contact:

    Yours sincerely,

    Alan S. Cornell

    School of Physics
    University of the Witwatersrand
    Private Bag 3
    Wits 2050
    South Africa

    Tel.:+27-11-717-6819

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