Topic: QCD thermodynamics with isospin density and magnetic fields

Quantum Chromodynamics (QCD) is the theory of the strong interactions that explains how the proton or the neutron (hadrons) are built up from elementary particles - quarks and gluons. QCD has a rich phase diagram: it exhibits among others a low-energy phase with hadronic degrees of freedom and a high-energy phase, where quarks are deconfined and the so-called quark-gluon plasma is formed. Detailed knowledge of this phase diagram help us understand the physics of various systems ranging from dense neutron stars through the early universe to heavy-ion collisions. The relevant parameters of the theory include the temperature, densities and background fields. The currently most successful approach to study the QCD phase diagram is via numerical Monte-Carlo simulation of the theory, discretized on a space-time lattice.
Within our research group, we use lattice simulations to determine the yet uncharted regions of the QCD phase diagram at nonzero (isospin) densities and background electromagnetic fields.

Host institute

University of Bielefeld March 2020 - June 2021
Goethe-University Frankfurt February 2016 - February 2020

Group members

Gergely Endrődi - group head
Bastian Brandt - Akad. Rat (2016-2021)
Francesca Cuteri - postdoc (2018-2019)
Gergely Markó - postdoc (2020-2021)
Sebastian Schmalzbauer - PhD student (2016-2020)
Sumir Motreedja - MSc student (2017-2018)
Max Theilig - MSc student (2017-2018)
Lukas Gonglach - MSc student (2017-2018)
Tobias Neitzel - MSc student (2016-2017)
Amine Chabane - BSc student (2019)

Bachelor and Master students looking for a thesis topic are welcome. Please contact us if you are interested!

Recent research

Topologically nontrivial ground states emerge in the spontaneously broken phase of a spin model [link] (click on the image to enlarge).
flat The magnetic permeability of strongly interacting matter is calculated with a new method [link]. Permeability
The early Universe can undergo pion condensation for large lepton asymmetry [link]. Cosmology The Dirac eigenvalues spread out in the complex plane as the isospin chemical potential grows. [link].
A low-energy approximation of QCD is improved to match lattice results on inverse magnetic catalysis [link]. NJL_B Charged pions decay orders of magnitude faster if exposed to strong magnetic fields [link]. pion_B
The equation of state of pion-condensed matter might allow for gravitationally bound configurations [link]. EoS_QCD The phase diagram of isospin-dense QCD exhibits a rich structure [link].
Figure represented in PRD's Kaleidoscope.
A generative neural network learns essential features of lattice scalar field theory [link]. GAN_vs_MC

The complete publication list of our group can be found on InSpire.

Our research is supported by the Emmy Noether Programme of the German Research Foundation under project number EN 1064/2-1.


Gergely Endrődi
Theoretical High Energy Group Homepage
Faculty of Physics, University of Bielefeld Email: endrodi(AT)
Universitätsstr. 25, 33615 Bielefeld Tel: 0521/106 - 2610
Office: E6-140 Fax: 0521/106 - 2961