Niels Benedikter

Niels Benedikter

Scientific Talks

Correlation Energy of the Fermi Gas

  • ICMP 2018 Montreal, contributed talk (July 2018)

Reformulation of the Dirac-Frenkel principle in terms of reduced density matrices and application to the derivation of Hartree-Fock and Bogoliubov-de-Gennes equations:

Interaction corrections to spin-wave theory of the ferromagnetic quantum Heisenberg model, and perturbative analysis of spin-waves at low temperature:

Derivation of the time-dependent Hartree-Fock equation for pure and mixed fermionic states in the mean-regime, and derivation of the Vlasov equation:

Quantitative Derivation of the Gross-Pitaevskii equation:

Slides of my PhD defence:

Anderson localization at large disorder on a lattice (method of fractional moments):

Fermionic coherent states with and without Grassmann numbers:

Dynamics of the radiative decay of excited atoms, rate of relaxation:

Existence of asymptotic fields in non-relativistic quantum electrodynamics:

Undergraduate Studies: Seminar Talks

In a 2+1 dimensional nonlinear Sigma model with Hopf term there exist topological excitations (skyrmions), which can have arbitrary spin (not necessarily integer or half-integer) and arbitrary quantum statistics (arbitrary phases under permutation of particles). Skyrmions have be found in experiments, see e.g. X. Z. Yu et al.
A short theoretical introduction to this interesting topic can be found in the book "Quantum Field Theory" by Kerson Huang (Wiley 1998) in the chapter on topological excitations.

Physics talks (in German) at the "Naturwissenschaftliches Kolleg" of the Studienstiftung (German National Academic Foundation).

  • Quantitative Derivation of the Gross-Pitaevskii Equation (November 2012)
  • Exact Renormalisation Group and Asymptotic Safety of Gravity (November 2011)
  • Homotopie-Gruppen für Physiker, Anyonen in 2+1 Dimensionen (Oktober 2010)
  • Konforme Feldtheorie (April 2010)
  • Majorana-Spinoren (September 2008)
  • Farbladungsspiel (September 2008)
  • Das Wu-Experiment (April 2008)