Conveners
Talks
- Gernot Eichmann
Talks
- Gernot Eichmann
Talks
- Joannis Papavassiliou
Talks
- Joannis Papavassiliou
Talks
- Peter Lowdon
Talks
- Peter Lowdon
Talks
- Maria Gomez Rocha
Talks
- Maria Gomez Rocha
Talks
- Jana N. Guenther (University of Wuppertal)
Talks
- Jana N. Guenther (University of Wuppertal)
Talks
- Liliana Apolinario (LIP (PT))
Talks
- Liliana Apolinario (LIP (PT))
Talks
- Markus Huber
Talks
- Bernd-Jochen Schaefer
Talks
- Bernd-Jochen Schaefer
Talks
- Sasa Prelovsek Komelj
Talks
- Sasa Prelovsek Komelj
The dynamics of strongly interacting quantum fields can to a large extent be described with relativistic fluid dynamics. This is based on an expansion around thermal equilibrium states and their extension to local equilibrium. The connection between the fluid description and the underlying quantum field theoretic description can be formulated in terms of linear and non-linear response theory....
The study of hadronic matter and its interactions is important for understanding Quantum Chromodynamics (QCD) in the context of hadron formation and structure. This talk will introduce briefly the physics program of the upcoming Compressed Baryonic Matter (CBM) experiment at the Facility for Antiproton and Ion Research (FAIR) in Darmstadt in nucleus-nucleus collisions and focus on its hadron...
In a first part I will deduce scaling dimensions by matching
the chirally broken gauge theory to the pion effective theory.
Consistency with soft theorems, the lattice and N=1 supersymmetric gauge theories will be discussed.
In a second part, I will consider how the interpretation extends to include a dilaton, the Goldstone due to spontaneous scale symmetry breaking. Gravitational form...
Parton showers are a cornerstone of high-energy physics phenomenology, modelling how energetic quarks and gluons radiate and fragment into jets of hadrons. While traditionally formulated in momentum space, a space-time understanding of parton showers remains elusive, even though it is essential to probe the underlying dynamics of QCD in both perturbative and semi-perturbative regimes. In this...
The description of complex phenomena in large multiplicity final states of high energy collisions require a detailed understanding of scattering amplitudes with many external legs, and how such amplitudes are ultimately projected onto the asymptotic final states observed in experiments. I will introduce how we develop theoretical frameworks and simulation methods which go beyond the...
M. Diez1, R. Alkofer1, and C. Kohlfรผrst2
1 Institute of Physics, University of Graz, NAWI Graz, Universitรคtsplatz 5, 8010 Graz, Austria
2 Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstraรe 400, 01328 Dresden, Germany
Pair creation in ultra-strong background fields, particularly the Sauter-Schwinger effect, has been a long-standing theoretical prediction. Despite extensive studies,...
Lattice simulations of real-time quantum field theory, as well as of various other systems, suffer from the infamous sign problem preventing the straightforward application of usual lattice approaches based on importance sampling. The complex Langevin method aims at bypassing the sign problem and is based on a stochastic evolution of complexified degrees of freedom in an artificial time...
Real time evolution in QFT poses a severe sign problem, which may be alleviated via a complex Langevin approach.
However, so far simulation results consistently fail to converge with a large real-time extent. A kernel in a complex Langevin equation is known to influence the appearance of the boundary terms and integration cycles, and thus kernel choice can improve the range of real-time...
I present a new formalism for meson physics,
which permits to venture beyond the traditional
rainbow-ladded approximation in a systematic way
We present a computation of electromagnetic form factors for pseudoscalar mesons within the BetheโSalpeter framework. For the spacelike region, we employ a flavor-dependent interaction kernel that accounts for dynamical quark mass effects through the quark-gluon vertex structure. This allows for a treatment of the electromagnetic current and accommodates mass asymmetries between quarks. In...
We present a description of the pion and nucleon based on solutions of the Bethe-Salpeter equation (BSE) constructed with phenomenological kernels in Minkowski space. The Nakanishi integral representation is employed to solve the pion BSE in Minkowski space, and various observables are computed. These include the charge form factor, which incorporates higher Fock-state contributions alongside...
The measurement of the $\chi_{c1}(3872)$ as the first heavy-light
four-quark candidate in 2003 was the start to exotic hadron
spectroscopy as we know it today. Over the following decades
many more exotic hadrons were measured and classified. In our work we
use the functional framework of Dyson-Schwinger and Bethe-Salpeter
equations to study the properties of these four-quark states...
The transverse part of the quark-gluon vertex in quenched QCD in Landau gauge is determined by solving a system of Dyson-Schwinger equations. We observe that the angular dependence of the calculated form factors appears to be relatively weak. However, we argue that this does not imply a planar degeneracy for this vertex, as even this slight dependence can significantly alter derived...
Fixed-point actions offer a powerful way to reduce discretization artifacts in lattice gauge theory, but their practical use has long been limited by the difficulty of finding accurate parametrizations. We address this challenge using machine learning with gauge-equivariant convolutional neural networks, which can represent general gauge-invariant structures on the lattice. This allows us to...
I will first briefly review the current state-of-the-art in calculating non-equilibrium processes in the early Universe, particularly in the context of baryogenesis and dark matter production. I will then focus on dark matter freeze-in, where various semi-classical Boltzmann approaches are employed in the literature and require careful scrutiny. I will present our recent calculation of...
Lattice QCD provides a unique, non-perturbative framework to map out the QCD phase diagram from first principles. This talk will outline what canโand cannotโcurrently be determined about the QCD phase diagram using lattice simulations. I will review how precise results for the equation of state and the transition temperature are obtained at vanishing baryon density. The challenges of extending...
We explore the emergence of color superconductivity in two-flavor QCD and its implications for the equation of state of dense matter inside neutron stars. Employing a quark-meson-diquark model truncation within the functional renormalization group framework, we study the interplay between diquark and chiral condensates and the resulting superconducting phase at high baryon density. Our...
Quantum Computing โ better and faster or just more hype?
The exploration of the phase diagram of quantum chromodynamics (QCD) is performed in
ultrarelativistic heavy-ion collision experiments, whereby the LHC and SPS facilities at CERN
Geneva and the RHIC at Brookhaven National Laboratory provide high-quality data on the
production of particles (hadrons and nuclei). While for the interpretation of the data a statistical
equilibrium approach...
Recognizing that flavor changing processes can probe new physics at scales beyond the reach of current experiments, we analyze semileptonic heavy meson, $B$, $B_s$ and $B_c$ decays using \emph{Relativistic Independent Quark Model - a QCD inspired model} emphasizing the harmonic potential model-dependent analysis. Our predicted branching fractions and physical observables such as...
I will briefly review the status and challenges of excited and exotic hadron spectroscopy using lattice QCD based on Eucledian-time. Selected results on exotic hadrons will be discussed. The challenges motivate progress for non-perturbative studies based on real-time evolution.
The discovery of the dimeson T_cc^+ at CERN 2021 at the predicted energy supported the successful application of the quark model beyond the 2-body and 3-body hadronic systems. Now, T_bb^- (and possibly T_bc^0) are expected to be strongly bound and decay only weakly. The search for T_bc^0 and T_bb^- continues and should be strongly encouraged. The reconstruction of the plethora of weak decays...
In the context of ultracold gases, hybrid ionโatom interaction systems, where charged polarons are formed, have become of significant interest for many fields, including condensed matter physics, solid-state systems, transport phenomena, quantum information, and quantum simulation. In this work, we investigate the properties of a charged polaron formed by an ion with finite momentum immersed...
We demonstrate, by providing two specific examples, that the local differential thermodynamic relations used as educated guesses in relativistic hydrodynamics with spin, do not hold even at global thermodynamic equilibrium. We show, by using a rigorous quantum statistical method, that for massless free fermions and massive free fermions with rotation and acceleration at global thermodynamic...
General Relativity theoretically allows the formation of black holes through the gravitational collapse of purely electromagnetic radiation. However, this scenario would involve electromagnetic strengths surpassing the critical Schwinger limit, resulting in the generation of electron-positron pairs. This quantum phenomenon counteracts the collapse, with the created particles scattering out of...
