[ NIKHEF theory group ]

Purpose

To meet, discuss, collaborate, generate ideas, share expertise, in the context of the FOM programme "Higgs as Probe and Portal"

We hope to see you here!

Agenda 21 September 2018

Time: 10.00 - 17.00
  • 10.25 - 11.00, H320:

    Michael Borinsky (Nikhef)
    Asymptotics and algebraic structure in perturbation theory

    Abstract: I will give an overview of two novel algebraic structures in QFT and how they provide a new perspective on the renormalon problem and perturbation theory at large order. Additionally, I will explain how these structures, emergent from QFT, can be used to gain insights on problems in statistical physics and graph theory.



  • 13.00 - 13.30, H320
    Plot of the Month/Pie of the Month



  • 15.00 - 16.00, H320
    Student meeting/discussion:

    Jacopo Fumagalli (Nikhef)
    The unique effective action

    Abstract: Everybody agree on this simple statement: physics should not depend on the choice of variables. However, in quantum field theory, this is less obvious than you have probably thought. In this blackboard lecture I will present a proposal from the eighties by Vilkovinsky to define a quantum theory invariant under field redefinitions. I will start by reviewing what the effective action is, its physical interpretation, ways of computing it and why the ``standard" procedure leads to field dependence. Then I will show how to define the unique effective action. In the end I will comment the more interesting case of gauge theories.



  • 16.30 - 17.00, H320

    Sabrina Cotogno (Nikhef)
    Spin correlations between partons inside the proton

    Abstract: In processes where two quarks are extracted from the proton to enter two separate hard scatterings (double parton scattering), the interparton correlations can have an impact on the size of the cross section and significantly alter the distributions of particles in the final state. In this work, we employ different models for the double parton distributions (DPDs) to study the quantum correlation between the spin of two quarks. We focus on the production of a pair of W bosons with the same electric charge and identify observables particularly promising for the experimental measurement of correlations at the LHC.



  • 17.00 Borrel