Lattice Gauge Theory group

GPU Research Center We are the lattice gauge theory group at the Eotvos University in Budapest, part of the Department of Theoretical Physics at the Faculty of Science.

Currently there are nine members and we are seeking new ones. Positions are available for PhD students and postdocs for 2 - 4 years appointments. If you are interested please email Sandor Katz at or Daniel Nogradi at

Our activities are and were funded by various funding agencies for which we are grateful, these include the Lendulet grant of the Hungarian Academy of Sciences, the OTKA-NF-104034 grant of OTKA and the EU Framework Programme 7 grant (FP7/2007-2013)/ERC No 208740.


Our primary interests are:

  • Chiral symmetry restoration and deconfinement in QCD with Wilson fermions
  • Finite chemical potential
  • QCD hadron spectrum
  • Eigenvalue distributions of the overlap Dirac operator
  • Strongly interacting Higgs sector - strong dynamics
  • Conformal gauge theories


Weekly ELFT seminars at the Department of Theoretical Physics

Location: 2nd floor, 2.54, Novobatzky room, 1117 Budapest, Pazmany Peter setany 1/a

If you'd like to receive seminar email announcements please write to

Time: Tuesdays at 14:15

See the archive for seminars since 2014.

  • 7 March 2023, Gyozo Kovacs (Wigner) slides

    Fate of the critical endpoint at large Nc

    The phase diagram of QCD is investigated by varying number of colors Nc within a Polyakov loop quark-meson chiral model. In particular, our attention is focused on the critical point(s); the critical point present for Nc=3 moves toward the mu_q-axis and disappears as soon as the number of color is increased. Yet, a distinct critical point emerges along the temperature axis for Nc=53 and moves toward finite density when increasing Nc further. Thus, the phase diagram at large Nc looks specular with respect to the Nc=3 results, with the first-order transition in the upper-left and crossover in the lower-right regions of the (mu_q,T)-plane. The pressure is also evaluated in dependence of Nc, showing a scaling with Nc^0 in the confined and chirally broken phase and with Nc^2 in the deconfined one. Moreover, the presence of a chirally symmetric but confined "quarkyonic phase" at large density and moderate temperature with a pressure proportional to Nc is confirmed.

  • 14 March 2023, Balazs Pozsgay (Eotvos)

    Exotic symmetries and breakdown of ergodicity from hard rod deformations

    We treat a new mechanism for ergodicity breaking in one dimensional quantum many body systems. We treat spin chains with local Hamiltonians, which have a special fine tuned form: there is interaction in the system, nevertheless the models have a large non-commutative symmetry algebra, generated by Matrix Product Operators (MPO). Meanwhile, the models are NOT integrable, and not exactly solvable. The exotic symmetries cause exact degeneracies in the finite volume spectrum, leading to a breakdown of thermalization. The mechanism we treat is a special type of ,,Hilbert space fragmentation''. It appears that our models are the first ones, where non-commutative MPO symmetries are found, such that the models are not integrable.

  • 21 March 2023, Mate Lencses (Wigner) slides

    Multicriticality in Yang--Lee edge singularity

    The Yang--Lee edge singularity is related to the anomalous behaviour of zeroes of the partition function in the two-dimensional Ising model. It was shown by Cardy, that this behaviour is described by the M(2,5) nonunitary minimal model of conformal field theory, known as the Yang--Lee model. This model can be realised as the Ising model above the critical temperature in an imaginary external magnetic field, as the point where the PT symmetry becomes spontaneously broken. In this talk, I will consider the analogue of this scenario in the tricritical Ising model, where a three-parameter family of nonunitary PT-symmetric flows exists. I will present our findings regarding massless flows ending in the Yang--Lee model and in a nonunitary "tricritical" point identified as M(2,7). Finally, I will discuss our conjecture on higher nonunitary multicritical points, connected by PT-symmetric nonunitary flows.

  • 28 March 2023, Arthur Hutsalyuk (Eotvos)

    Finite temperature spin diffusion in the Hubbard model in the strong coupling limit

    We investigate finite temperature spin transport in one spatial dimension by considering the spin-spin correlation function of the Hubbard model in the limiting case of infinitely strong repulsion. We find that in the absence of bias the transport is diffusive, and derive the spin diffusion constant. Our approach is based on asymptotic analysis of a Fredholm determinant representation, which is entirely analytic and free of phenomenological assumptions of Generalized Hydrodynamics.

    Based on arXiv:2301.13840, O. Gamayun et. al.

  • 4 April 2023, Zoltan Bajnok (Wigner)

    The full analytic trans-series in integrable field theories

    We analyze a family of generalized energy densities in integrable quantum field theories in the presence of an external field coupled to a conserved charge. By using the Wiener-Hopf technique to solve the linear thermodynamic Bethe ansatz equations we derive the full analytic trans-series for these observables in terms of a perturbatively defined basis. We show how to calculate these basis elements to high orders analytically and reveal their complete resurgence structure. We demonstrate that the physical value of the generalized energy densities is obtained by the median resummation of their ambiguity-free trans-series.

  • 11 April 2023, David Pesznyak (ELTE)


  • 9 May 2023, Janos Takatsy (Wigner)


For students

Our group offers BSc/MSc diploma, PhD and TDK topics in Lattice Field Theory.

Please contact Sandor: or Daniel: in case you are interested.

Current topics include:

  • QCD thermodynamics
  • 2 and 4 dimensional CFT
  • Beyond Standard Model


Matteo Giordano

assistant professor

2009 PhD - University of Pisa, Italy

2010-2010 postdoc - IPhT/CEA-Saclay, France

2010-2012 postdoc - University of Zaragoza, Spain

2012-2015 postdoc - ATOMKI, Debrecen, Hungary

2015-2018 postdoc - Eotvos University, Budapest, Hungary

Kornel Kapas

PhD student

2018- Eotvos University, Hungary









Sandor Katz


2001 PhD - Eotvos University, Hungary

2001-2003 postdoc - DESY, Hamburg, Germany

2003-2005 postdoc - University of Wuppertal, Germany

2006-2012 assistant professor - Eotvos University, Hungary

2012- professor - Eotvos University, Hungary

Tamas Kovacs


1996 PhD - UCLA, USA

1996-1998 postdoc - University of Colorado, Boulder, USA

1998-2000 postdoc - University of Leiden, the Netherlands

2000-2002 postdoc - DESY, Zeuthen, Germany

2002-2011 professor - University of Pecs, Hungary

2011- senior researcher - ATOMKI, Debrecen, Hungary

2020- professor, Eotvos University, Hungary

Daniel Nogradi


2005 PhD - University of Leiden, the Netherlands

2005-2007 postdoc - University of Wuppertal, Germany

2007-2009 postdoc - UCSD, USA

2009-2011 senior research fellow - Eotvos University, Budapest

2012 - 2020 assistant professor - Eotvos University, Budapest

2020- professor - Eotvos University, Budapest

Attila Pasztor


2015 PhD - Eotvos University, Hungary

2016-2018 postdoc - Wuppertal University, Germany

2018- postdoc - Eotvos University, Hungary






Lorinc Szikszai

PhD student

2016- Eotvos University, Hungary






Zoltan Tulipant


2020 PhD - University of Debrecen, Hungary

2020 - postdoc - Eotvos University, Hungary





Former members

Gergely Endrodi

2009 PhD - Eotvos University, Hungary

2010-2015 postdoc - University of Regensburg, Germany

2016- Emmy Noether group leader - University of Frankfurt, Germany

2020- professor - University of Bielefeld, Germany

Santanu Mondal

2013 PhD - University of Calcutta, India

2013-2016 postdoc - Eotvos University, Hungary

2016-2018 postdoc - National Chiao Tung University, Taiwan

2018- postdoc - Los Alamos National Laboratory, USA

Ferenc Pittler

2013 PhD - University of Pecs, Hungary

2013-2016 postdoc - Eotvos University, Budapest

2017- postdoc - Bonn University, Germany

Csaba Torok

2017 PhD - Eotvos University, Hungary

2017- postdoc - Wuppertal University, Germany


Balint Toth

2005-2006 research assistant - University of Wuppertal, Germany

2007 assistant lecturer - University of Pecs, Hungary

2010 PhD - Eotvos University, Hungary

2010- postdoc - University of Wuppertal, Germany



Norbert Trombitas

PhD student

2015 PhD - Eotvos University, Hungary



Zoltan Varga

PhD student

2018- Eotvos University, Hungary




Since it is tricky to locate all papers by a large number of people whose names are not unique on inspire, you can try various search queries:


Our group has access to a number of high performance computer installations in Europe and also maintains several PC and GPU clusters on site in Budapest.

For visitors

Our department is on the Buda side of the Danube very close to the Petofi Bridge, the address is Budapest 1117, Pazmany Peter setany 1/A:

The Department of Theoretical Physics is on the sixth floor opposite the Danube facing side of the building: