title: Towards finite density properties and real-time dynamics in strongly correlated systems
creator: Ziegler, Felix Paul Gerhard
subject: 530
subject: 530 Physics
description: In this thesis we study strongly correlated quantum systems in extreme temperature and  density conditions. A prominent example is the quark-gluon plasma produced in ultra-  relativistic heavy-ion collisions. Since the degrees of freedom in the systems of interest are  strongly coupled the use of non-perturbative methods is required. Our working method  is lattice field theory allowing for high precision ab-initio calculations of physical quan-  tities based on Monte Carlo simulations. We study QCD-like theories at finite density.  This introduces the sign problem to the lattice preventing the applicability of importance  sampling algorithms. Promising methods to tackle the sign problem are the Complex  Langevin evolution on the one hand and Lefschetz Thimbles on the other hand. In this  work we propose novel algorithmic ideas to both approaches which are put to work in  simple models with a sign problem as well as in lattice gauge theories. Moreover, we in-  vestigate real-time properties of quantum systems at finite temperature which is necessary  for the computation of transport coefficients. To that end we conduct lattice simulations  in imaginary time which are aimed at improving the spectral reconstruction of thermal  features. Moreover, we study simulations directly in real-time by means of the Complex  Langevin evolution equipped with variable transformations.
date: 2019
type: Dissertation
type: info:eu-repo/semantics/doctoralThesis
type: NonPeerReviewed
format: application/pdf
identifier: https://archiv.ub.uni-heidelberg.de/volltextserverhttps://archiv.ub.uni-heidelberg.de/volltextserver/26918/1/Dissertation_Ziegler.pdf
identifier: DOI:10.11588/heidok.00026918
identifier: urn:nbn:de:bsz:16-heidok-269189
identifier:   Ziegler, Felix Paul Gerhard  (2019) Towards finite density properties and real-time dynamics in strongly correlated systems.  [Dissertation]     
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/26918/
rights: info:eu-repo/semantics/openAccess
rights: http://archiv.ub.uni-heidelberg.de/volltextserver/help/license_urhg.html
language: eng