We study the scattering of the gluon-dressed physical quarks, defined as the eigenstates of the vacuum QCD Hamiltonian, off a colored medium. We solve the wave function of the physical quark state by diagonalizing the QCD Hamiltonian in vacuum in a <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">|</mo><mi>q</mi><mo stretchy="false">⟩</mo><mo>+</mo><mo stretchy="false">|</mo><mrow><mi>q</mi><mi>g</mi></mrow><mo stretchy="false">⟩</mo></math> Fock space, with implementing the sector-dependent mass renormalization scheme. We then perform numerical simulations of the real-time quantum state evolution of the initially dressed quark state at various medium densities. The results are compared with those of an initially bare or off-shell quark states. With the obtained light-front wave function of the evolved state, we extract the quark jet transverse momentum broadening, the quenching parameter, the cross section, the gluon emission rate, and the evolution of the invariant mass. The scenario considered is relevant for high energy scattering processes, where the quark originates from far outside the color field describing the scattering target. This investigation on dressed quarks complements our earlier studies of the single quark scattering in the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">|</mo><mi>q</mi><mo stretchy="false">⟩</mo></math> Fock space, and of the bare quark scattering in the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">|</mo><mi>q</mi><mo stretchy="false">⟩</mo><mo>+</mo><mo stretchy="false">|</mo><mrow><mi>q</mi><mi>g</mi></mrow><mo stretchy="false">⟩</mo></math> Fock space, providing a novel systematic description of quark scattering process using a nonperturbative formalism.

Spain

Meijian Li

Finland

Tuomas Lappi

China

Xingbo Zhao

Carlos A. Salgado

Scattering and gluon emission of physical quarks in a SU(3) colored field

Higher order calculations in chiral gauge theories such as the Electroweak Standard Model require a sound treatment of the notoriously problematic $\textit{γ}$ -matrix in Dimensional Regularization (DReg). In the all-order consistent BMHV scheme anticommutativity has to be sacrificed, resulting in spurious breakings of BRST invariance, the restoration of which necessitates finite, symmetry-restoring counterterms. Following recent advances in successfully applying this scheme to multi-loop calculations for Abelian models, we shall here present the first complete non-Abelian two-loop result for the case of SU(2), which is of particular interest to the Standard Model. We provide the complete list of finite, two-loop symmetry-restoring counterterms and discuss intricacies of the non-Abelian implementation. Except for one novel term, the finite counterterm action exhibits the same structure as at one-loop order.

Germany

Paul Kühler

Dominik Stöckinger

Two-loop renormalization of a chiral SU(2) gauge theory in dimensional regularization with non-anticommuting $\textit{γ}$

We investigate the phase diagram of the three-dimensional SU(3) spin model with finite chemical potential, which is an effective Polyakov loop model for finite density QCD, using the tensor renormalization group method. We successfully determine the location of the critical endpoints being free from the complex action problem in the standard Monte Carlo approach. The critical values of the parameters show the consistency with previous ones obtained by other analytic and numerical methods.

Japan

Xiao Luo

Yoshinobu Kuramashi

Critical endpoints of three-dimensional finite density SU(3) spin model with tensor renormalization group

We revisit the doublet–triplet splitting problem within the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>S</mi><mi>U</mi><mo stretchy="false">(</mo><mn>5</mn><mo stretchy="false">)</mo></math> gauge group framework to advocate a viable regime with the light scalar leptoquark of the doublet–triplet splitting notoriety that is compatible with the current experimental bounds on partial proton decay lifetimes. We explicitly demonstrate, through a consistent use of higher-dimensional operators, how to implement suppression of baryon number violating interactions of the aforementioned color triplet. Our study thus offers an alternative approach to the doublet-triplet splitting problem as it removes a need for an extreme mass hierarchy between the partners residing in the same representation. We furthermore pursue two different extensions of two distinct symmetry breaking scenarios of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>S</mi><mi>U</mi><mo stretchy="false">(</mo><mn>5</mn><mo stretchy="false">)</mo></math>, one with a 24-dimensional representation and the other one with a 75-dimensional representation, to produce comparative study of novel consequences for the gauge coupling unification and the one-loop level neutrino mass generation. Our results point toward qualitatively novel <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>S</mi><mi>U</mi><mo stretchy="false">(</mo><mn>5</mn><mo stretchy="false">)</mo></math> scenarios, where the light scalar leptoquarks, responsible for the neutrino mass generation, might be even accessible at colliders and thus serve as an accelerator accessible portal to the high-scale physics.

Croatia

Slovenia

Ilja Doršner

Mijo Matković

Shaikh Saad

Nonrenormalizable SU(5) GUTs: Leptoquark-induced neutrino masses

This article investigates the thermodynamic properties of the SU(2) Nambu–Jona–Lasinio (NJL) model under the chiral chemical potential $$ \mu _5 $$ , employing Tsallis non-extensive statistics. The introduction of the parameter $$ q $$ , which characterizes the non-extensivity of the system through Tsallis statistics, offers a novel perspective for studying the behavior of strongly interacting matter under extreme conditions. By calculating thermodynamic quantities such as quark mass, critical temperature, chiral density, pressure, entropy, and speed of sound, we systematically analyze the effects of $$ \mu _5 $$ and $$ q $$ on these quantities. It is observed that both $$ \mu _5 $$ and $$ q $$ exhibit an inverse relationship with the critical temperature $$ T_\textrm{pc} $$ , while showing a positive correlation with the chiral density $$\left\langle n_{5}\right\rangle $$ .

Xiang-Qiong Liu

The QCD phase diagram of the SU(2) NJL model with chiral chemical potential under a non-extensive framework

An <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>SU</mi></mrow><mo stretchy="false">(</mo><mn>8</mn><mo stretchy="false">)</mo></math> theory was previously found to be the minimal simple gauge group where all three-generational Standard Model (SM) fermions can be nontrivially embedded. It is maximally broken into a subgroup of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>SU</mi></mrow><mo stretchy="false">(</mo><mn>8</mn><mo stretchy="false">)</mo><mo stretchy="false">→</mo><msub><mi mathvariant="script">G</mi><mn>441</mn></msub><mo>≡</mo><mrow><mi>SU</mi></mrow><mo stretchy="false">(</mo><mn>4</mn><msub><mo stretchy="false">)</mo><mi>s</mi></msub><mo stretchy="false">⊗</mo><mrow><mi>SU</mi></mrow><mo stretchy="false">(</mo><mn>4</mn><msub><mo stretchy="false">)</mo><mi>W</mi></msub><mo stretchy="false">⊗</mo><mi mathvariant="normal">U</mi><mo stretchy="false">(</mo><mn>1</mn><msub><mo stretchy="false">)</mo><msub><mi>X</mi><mn>0</mn></msub></msub></math> at the grand unified theory scale by the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>SU</mi></mrow><mo stretchy="false">(</mo><mn>8</mn><mo stretchy="false">)</mo></math> adjoint Higgs field of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn mathvariant="bold">6</mn><msub><mn mathvariant="bold">3</mn><mi mathvariant="bold">H</mi></msub></mrow></math>. Gauge symmetries in the strong and the weak sectors are extended by one and two ranks, respectively. The sequential strong-weak-weak (SWW) symmetry breaking stages were found to generate the observed hierarchical SM quark/lepton masses as well as the Cabibbo-Kobayashi-Maskawa mixing pattern with the precise flavor identifications [The global <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi mathvariant="normal">B</mi><mo stretchy="false">−</mo></mrow></math> L symmetry in the flavor-unified SU(N) theories, <a href="http://dx.doi.org/10.1007/JHEP04(2024)046">J. High Energy Phys. 04 (2024) 046</a>. and The standard model quark/lepton masses and the Cabibbo-Kobayashi-Maskawa mixing in an SU(8) theory, <a href="http://dx.doi.org/10.1007/JHEP12(2024)137">J. High Energy Phys. 12 (2024) 137</a>.]. We further study the possible weak-strong-weak and weak-weak-strong symmetry breaking patterns and compare with the results that we have obtained by following the SWW sequence. The two-loop renormalization group equations following both patterns are analyzed, where we cannot achieve the gauge coupling unification in the field theory framework. Through these analyses, we suggest the gauge coupling unification to be interpreted in the context of the affine Lie algebra.

Ning Chen

Zhiyuan Chen

Zhanpeng Hou

Zhaolong Teng

Bin Wang

Further study of the maximally symmetry breaking patterns in an <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>SU</mi></mrow><mo stretchy="false">(</mo><mn>8</mn><mo stretchy="false">)</mo></math> theory

In this work, we explored and experimented with new forms of parameterized quantum circuits to be used as variational ansatzes for solving the bosonic and supersymmetric $\textit{SU}$(2) matrix models at different couplings using the variational quantum Eigensolver (VQE) algorithm. Working with IBM quantum computing platform, we show that two types of quantum circuits named and can outperform the popular circuits which have been routinely used in the recent quantum physics literature to run VQE. With their more customizable constructions that allow for more flexibility beyond choosing the types of parameterized rotation gates, both types of new circuit ansatzes used in this work have led to performances that are either better than or at least comparable to in the setting of $\textit{SU}$(2) matrix models. In particular, in the strong coupling regime of the bosonic model, both and circuits provided a better approximation to the exact ground state, while in the supersymmetric model, shallow circuits, with a small number of parameters, attained a comparable or even better performance compared to the much deeper circuits with around 8 to 9 times more parameters. The results of this work demonstrate conclusively the potential of and quantum circuits as efficient new types of variational ansatzes that should be considered more frequently in future VQE studies of quantum physics systems.

Singapore

Harriet Dao

Exploring new variational quantum circuit ansatzes for solving $\textit{SU}$(2) matrix models

We study the confining and deconfining phases of pure SU(3) lattice gauge theory with topological data analysis. This provides unique insights into long range correlations of field configurations across the confinement-deconfinement transition. Specifically, we analyze nontrivial structures in electric and magnetic field energy densities as well as Polyakov loop traces and a Polyakov loop-based variant of the topological density. The Betti curves for filtrations based on the electric and magnetic field energy densities reveal signals of electromagnetic dualities. These dualities can be associated with an interchange in the roles of local lumps of electric and magnetic energy densities around the phase transition. Moreover, we show that plaquette susceptibilities can manifest in the geometric features captured by the Betti curves. We also compare these findings against earlier results for SU(2) and elaborate on the significant differences. Our results demonstrate that topological data analysis can identify clear differences between phase transitions of first and second order for non-Abelian lattice gauge theories and provides unprecedented insights into the relevant structures in their vicinity.

Daniel Spitz

United States

Julian M. Urban

Jan M. Pawlowski

Topological data analysis of the deconfinement transition in SU(3) lattice gauge theory

We present a quantum computational framework for pure SU(2) lattice gauge theory, using continuous variables instead of discrete qubits to represent the infinite-dimensional Hilbert space of the gauge fields. We consider a ladder as well as a two-dimensional grid of plaquettes, detailing the use of gauge fixing to reduce the degrees of freedom and simplify the Hamiltonian. We demonstrate how system dynamics, ground states, and energy gaps can be computed using the continuous-variable approach to quantum computing. Our results indicate that it is feasible to study non-Abelian gauge theories with continuous variables, providing new avenues for understanding the real-time dynamics of quantum field theories.

Victor Ale

Nora Bauer

Raghav Jha

Felix Ringer

George Siopsis

Quantum computation of SU(2) lattice gauge theory with continuous variables

In this paper, we discuss the predicted proton lifetimes in minimal supersymmetric (SUSY) $\textit{SU}$(5) grand unified theory (GUT) with gauge mediated supersymmetry breaking (GMSB). We focus on the case of $$\textbf{5} + \bar{\textbf{5}}$$ messengers and determine the low-scale mass spectrum of the scalar particles and gauginos using the renormalization group equations. With the obtained mass spectrum, we calculate the dominant proton decay mode for SUSY $\textit{SU}$(5) GUT, $$p \rightarrow K^+ \bar{\nu }$$ . In our setup, we assume the messenger scale to be $$\mathcal {O}(10^3)$$ TeV in order to obtain a proper Higgs mass in GMSB scenario. For this messenger scale, we find the proton lifetime is consistent with current experimental limits and can be tested by future proton decay experiments.

Jason Evans

Yoshihiro Shigekami

Proton Lifetime in Minimal Supersymmetric SU(5) with Gauge Mediation