We propose a novel realization of the linear seesaw model with a non-invertible selection rule, assisted by $\mathbb{Z}_3$ symmetry. In our framework, Dirac mass matrices are generated at the one-loop level, breaking the non-invertible symmetry, while the symmetry remains intact at tree level. In addition to active neutrino masses, the model exhibits rich and testable phenomenology, including non-unitarity constraints, lepton flavor violation, lepton anomalous magnetic moments, and a dark matter candidate. After describing our model, we carry out a numerical analysis and present results for our physical parameters.

China

Hiroshi Okada

Slovenia

India

Yutaro Shoji

A novel realization of linear seesaw model in a non-invertible selection rule with the assistance of ${\mathbb{Z}_3}$ symmetry * Hiroshi Okada is supported by Zhongyuan Talent (Talent Recruitment Series) Foreign Experts Project. Yutaro Shoji is supported by the Slovenian Research Agency under the research grant J1-4389

An effective field theory framework is developed to study the interaction of heavy quarks in strongly coupled quark-gluon plasma (QGP). The latter is treated as a relativistic non-dissipative colorless fluid which can be studied using a derivatively coupled effective field theory based on previous work. Coupling this to heavy quarks provides a systematic way to obtain the interaction between the heavy quark and phonons, excitations of the fluid. In particular we calculate the quasiparticle width of heavy quark to phonon and phonon-heavy quark scattering in a thermal medium.

United States

Andreas Kirchner

Berndt Müller

Jyotirmoy Roy

Chathuranga Sirimanna

A new effective field theory for heavy quarks in the quark-gluon plasma

Quantum energy teleportation (QET) has been studied in continuum field theory and in lattice many-body systems, but the relation between the two within a single interacting model is still not well understood. To address this question, we consider the massive Thirring model, equivalently the sine-Gordon theory. In the continuum, the trigonometric measurement is a weak binary positive operator-valued measure (POVM), and its leading signal is set by a conserved-current correlator in the bosonized theory, with both gapless behavior and gapped large-distance asymptotics. On the lattice, the conventional protocol does not access this neutral current sector. For Alice’s local measurement, a lattice <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>U</mi><mo stretchy="false">(</mo><mn>1</mn><mo stretchy="false">)</mo></mrow></math> selection rule removes the neutral current contribution from Bob’s subsystem, and the separated signal lies in charged sectors. On the same lattice Hamiltonian we construct a neutral current protocol whose weak signal is exactly a coarse-grained current correlator and whose extracted energy scales quadratically with the measurement strength. This identifies the neutral sector shared by the lattice and continuum descriptions, while separating it from the charged sector that governs the conventional qubit protocol.

Kazuki Ikeda

Quantum energy teleportation across a lattice and the continuum

We perform a quantum probing of colliding plane-wave spacetimes. In particular, we consider the Khan-Penrose and the Ferrari-Ibáñez solutions, which admit a strong and a weak singularity after the two waves collide. While we find that, like Schwarzschild, for the Khan-Penrose solution the singularity cannot be probed by quantum-field theory, the Ferrari-Ibáñez singularity can be traversed. Our results culminate in a quantum Weyl conjecture: The significant geometric property to classify spacetimes with respect to quantum probes is given by the Coulomb part of the Weyl tensor. We then use this conjecture to sketch a possible backreaction scenario for plane waves.

Germany

Ivo Sachs

Spain

Marc Schneider

Probing of colliding wave spacetimes and a quantum Weyl conjecture

We explore a portal vectorlike lepton (pVLL) extension of the Standard Model (SM) and study its implications for Higgs and vector-boson associated production (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>h</mi><mi>V</mi></math>, with <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>V</mi><mo>=</mo><mi>Z</mi></math>-boson or dark photon) at a future muon collider facility. We show that while the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>μ</mi><mo>+</mo></msup><msup><mi>μ</mi><mo>−</mo></msup><mo stretchy="false">→</mo><mi>h</mi><mi>Z</mi></math> production rate remains close to its SM prediction in a wide range of parameter space, the rate for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>μ</mi><mo>+</mo></msup><msup><mi>μ</mi><mo>−</mo></msup><mo stretchy="false">→</mo><mi>h</mi><msub><mi>γ</mi><mi>d</mi></msub></math> can be substantially enhanced owing to the nondecoupling nature of the interaction involving the heavy lepton, the muon and the dark photon. We demonstrate that the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>h</mi><msub><mi>γ</mi><mi>d</mi></msub></math> production rate can exceed the corresponding <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>h</mi><mi>Z</mi></math> rate by a factor of 1–100 within the perturbative unitarity limit, making it a promising channel for probing Higgs interactions and potential new physics effects. We also examine the role of the pVLL state in the context of dark matter (DM) phenomenology and identify regions of parameter space consistent with the observed relic abundance by extending the simplified setup with a viable DM candidate. The <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>h</mi><msub><mi>γ</mi><mi>d</mi></msub></math> production can also be used to constrain the dark photon mass (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>m</mi><msub><mi>γ</mi><mi>d</mi></msub></msub></math>) and/or the dark gauge coupling (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>g</mi><mi>d</mi></msub></math>) consistent with various constraints including the current muon <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>g</mi><mo>−</mo><mn>2</mn></math> measurements within the pVLL framework. We perform a detailed collider analysis of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>h</mi><msub><mi>γ</mi><mi>d</mi></msub></math> process in the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>b</mi><mover accent="true"><mi>b</mi><mo stretchy="false">¯</mo></mover><mo>+</mo></math> missing energy final state. A <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>2</mn><mi>σ</mi></math> exclusion limit for <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>m</mi><msub><mi>γ</mi><mi>d</mi></msub></msub></math> up to 80 GeV is obtained assuming <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>g</mi><mi>d</mi></msub><mo>=</mo><mn>0.05</mn></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>sin</mi><msub><mi>θ</mi><mi>L</mi></msub><mo>=</mo><mn>4</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>5</mn></mrow></msup></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>sin</mi><msub><mi>θ</mi><mi>s</mi></msub><mo>=</mo><mn>0.05</mn></math>, for a heavy lepton mass <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo>∼</mo><mn>3</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi></math> at a 3 TeV muon collider with an integrated luminosity of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>1</mn><mtext> </mtext><mtext> </mtext><msup><mrow><mi>ab</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math>.

Krishna Tewary

Sanjoy Biswas

Shivam Verma

Implications of a portal vectorlike lepton on associated Higgs boson production at a multi-TeV muon collider

We simulate a self-interacting three-flavor neutrino system within a core-collapse supernova using a hybrid classical-quantum algorithm on a qutrit computer. Based on the Dirac-Frenkel evolution equations, we employ a variation of the quantum-assisted simulator to calculate the system’s time evolution operator by performing qutrit Hadamard tests to find expectation values of unitary operators in the Hamiltonian. The time evolution simulation is then done classically. We find that the hybrid algorithm produces results comparable to an exact numerical integration out to times of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>t</mi><mo>≈</mo><mn>30</mn><msubsup><mrow><mi>ω</mi></mrow><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msubsup></mrow></math> with time step <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>δ</mi><mi>t</mi><mo>=</mo><mn>0.005</mn><msubsup><mrow><mi>ω</mi></mrow><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msubsup></mrow></math>, where <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>ω</mi><mn>0</mn></msub></math> is the energy scale of the single neutrino vacuum oscillations. We discuss the lessons learned in simulating neutrino systems using this hybrid quantum-classical algorithm, along with the advantages it offers over quantum Trotterization.

Daniel J. Heimsoth

Pooja Siwach

A. Baha Balantekin

Three-flavor supernova neutrino simulation using a hybrid quantum-classical algorithm with qutrits

We apply harmonic analysis to study the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>T</mi><mover accent="true"><mi>T</mi><mo stretchy="false">¯</mo></mover></math>-deformed torus partition function. We first express the CFT partition functions in terms of Maass waveforms, including the Eisenstein series and cusp forms. These basis functions turn out to deform in a very simple way under the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>T</mi><mover accent="true"><mi>T</mi><mo stretchy="false">¯</mo></mover></math> deformation. The spectral decomposition provides a numerically stable and efficient method to compute the partition function at finite values of the deformation parameter <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>λ</mi></math>, allowing us to clearly resolve the analytic structure of the partition function as a function of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>λ</mi></math>. The resulting deformed partition function exhibits a Hagedorn singularity. Building on the harmonic analysis approach, we propose a natural analytic continuation beyond the Hagedorn singularity, which enables us to compute the full partition function for any value of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>λ</mi></math>.

Jie Gu

United Kingdom

Jue Hou

Yunfeng Jiang

Beyond Hagedorn: A Harmonic Approach to <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>T</mi><mover accent="true"><mrow><mi>T</mi></mrow><mrow><mo stretchy="false">¯</mo></mrow></mover></mrow></math> Deformation

We study the local horizon residue and minimally coupled massless-scalar quasinormal modes of the logarithmic connection-hair background obtained perturbatively in the quadratic model $$f(Q)=Q+\alpha Q^2$$ . After mass renormalization the displayed order- $$\alpha ^2$$ blackening function is $$F(r)=1-[2M+\eta \ln (r/r_\star )]/r$$ , with $$\eta =\alpha ^2\mu $$ . Euclidean regularity and the simple pole of 1/$\textit{F}$ give the same Hawking temperature, while the same residue multiplies the near-horizon logarithm of the scalar tortoise coordinate. We derive the massless-scalar master equation, its effective potential, the photon-sphere equation, and the controlled first-order shifts of the eikonal scalar frequency and damping rate. We do not identify the integration parameter $\textit{M}$ with a Hamiltonian or Noether mass: the logarithmic tail leaves the perturbative regime at large radius and does not satisfy the standard falloff required for a finite ADM charge. Consequently no physical entropy, heat capacity, Ruppeiner metric, or gravitational quasinormal-mode spectrum is claimed. For comparison only, we retain an explicitly labelled auxiliary Hessian construction and an algebraic evaluation of the resummed truncated metric at $$r_h=2\eta $$ . That point has $$|\eta |/r_h=1/2$$ and is therefore outside perturbative control; its finite scalar null-orbit and WKB frequencies are properties of the truncated function, not predictions of quadratic $\textit{f}$($\textit{Q}$) gravity. The controlled result is the local temperature–scalar-monodromy residue identity and the distinct small-hair shifts sampled at the horizon and photon sphere.

Wen-Xiang Chen

Horizon residues and test-scalar quasinormal modes of a perturbative Schwarzschild-type black hole in quadratic $\textit{f}$($\textit{Q}$) gravity

We develop a real-time Wigner-functional lattice framework with positive Hartree-Gaussian initial sampling and introduce a connected-cluster survival criterion for extracting false vacuum decay rates across the crossover from quantum fluctuations to thermal nucleation. At high temperatures, the connected-cluster rate agrees well with the Hartree-resummed thermal nucleation benchmark, while the commonly used global-survival criterion can give substantially smaller rates because of multiseed dynamics and global averaging. At low temperatures, the connected-cluster and global-survival rates approach each other in the dilute-event regime, whereas the false vacuum fraction observable can be contaminated by transient spatial conversion and kink-antikink reflection. Our results clarify how different real-time observables encode distinct aspects of metastable decay.

Haiyang Wang

Renhui Qin

Ligong Bian

False vacuum decay across the quantum-to-thermal crossover: A comparison of real-time observables

We propose a novel model for pseudo-scalar dark matter (PSDM) by extending the Standard Model (SM) with a dark gauged $\textit{U}$ (1) symmetry, but without dark charged fermions. We impose a $\textit{Z}$ symmetry to ensure the stability of pseudo-scalar dark matter and regard the $\textit{U}$ (1) symmetry as being broken dominantly by a large VEV of the singlet scalar field. The would-be Goldstone associated with the $\textit{U}$ (1) gauge boson is almost orthogonal to the direction of PSDM. As a result, we show that PSDM appears as a stable pseudo-Nambu-Goldstone boson receiving the mass from the $\textit{U}$ (1) invariant mixing potential and the corresponding cross section for direct detection gets suppressed even for the weak-scale mass of PSDM. We also show that the correct relic density can be explained by the PSDM annihilations into the SM particles or into a pair of light Higgs-like scalars, being compatible with the bounds from Higgs invisible decay, Higgs data and indirect detection.