We present an analytic calculation of the integrated double-emission eikonal function of a massive and a massless emitter whose momenta are at an arbitrary angle to each other. This quantity provides one of the required ingredients for extending the nested soft-collinear subtraction scheme to processes with massive final-state particles. To calculate it, we use the standard methodology involving reverse unitarity and its extension to cases with Heaviside functions, integration-by-parts technology and reduction to master integrals, and differential equations. In addition, we also describe a semi-numerical method based on the subtraction of infra-red and collinear singularities from the eikonal function, allowing us to extract divergences of the integrated eikonal function analytically, and to derive a simple integral representation for the finite remainder.

Germany

Dennis Horstmann

Kirill Melnikov

Ming-Ming Long

Andrey Pikelner

Integral of the double-emission eikonal function for a massive and a massless emitter at an arbitrary angle

We study the sphere partition function of 3d $$ \mathcal{N} $$ = 2 holographic SCFTs arising on the worldvolume of $\textit{N}$ coincident M2-branes in the presence of squashing and real mass deformations. We argue that the all-order large $\textit{N}$ perturbative expansion of the partition function resums into a compact expression in terms of an Airy function. We provide ample evidence for this conjecture using numerical methods, saddle point analysis in the ’t Hooft limit, and the relation of the squashed sphere partition function to the Cardy-like limit of the superconformal index. We also discuss the relation of our results to topological string theory and the statistical mechanics of Fermi gases. Our conjecture has a bearing on the AdS/CFT correspondence and the structure of perturbative M-theory corrections to 11d supergravity which we discuss.

Belgium

Nikolay Bobev

Pieter-Jan Smet

South Korea

Junho Hong

France

Valentin Reys

China

Xuao Zhang

An Airy tale at large $\textit{N}$

We introduce a new approach to modeling transition distribution amplitudes (TDAs) for the processes <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>e</mi><mi>p</mi><mo stretchy="false">→</mo><mi>e</mi><mi>n</mi><msup><mi>π</mi><mo>+</mo></msup></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>e</mi><mi>p</mi><mo stretchy="false">→</mo><mi>e</mi><mi>p</mi><msup><mi>π</mi><mn>0</mn></msup></math>. The modeling is flexible, constrained by sparsely available experimental data, and satisfies theoretical requirements, including reduction to nucleon distribution amplitudes in the appropriate limit. We study the sensitivity of observable predictions to various modeling assumptions. We discuss unpolarized cross sections, as well as the three nonvanishing polarization observables at leading twist, namely, the single transverse target spin asymmetry and the two double spin asymmetries that occur with a polarized lepton beam on either a longitudinally or transversely polarized target. The analysis is complemented by a simple Monte Carlo study to provide guidance for exploring exclusive processes in the so-called backward kinematics. Our work aims to highlight the importance of future measurements to better constrain TDAs and to support upcoming experimental proposals.

B. Pire

Russia

K. Semenov-Tian-Shansky

Poland

P. Sznajder

L. Szymanowski

Toward an advanced phenomenology of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>π</mi><mi>N</mi></math> transition distribution amplitudes

We study 2d dilaton gravity theories with a periodic potential, with special emphasis on sine dilaton gravity, which is holographically dual to double-scaled SYK. The periodicity of the potentials implies a symmetry under (discrete) shifts in the momentum conjugate to the length of geodesic slices. This results in divergences. The correct definition is to gauge this symmetry. This discretizes the geodesic lengths. Lengths below a certain threshold are null states. Because of these null states, the entropy deviates drastically from Bekenstein-Hawking and the Hilbert space becomes finite dimensional. The spacetimes have a periodic radial coordinate. These are toy models of 2d quantum cosmology with a normalizable wavefunction. We study two limiting dualities: one between flat space quantum gravity and the Heisenberg algebra, and one between topological gravity and the Gaussian matrix integral. We propose an exact density of states for certain classes of periodic dilaton gravity models.

United States

Italy

Andreas Blommaert

Adam Levine

Thomas Mertens

Jacopo Papalini

Klaas Parmentier

An entropic puzzle in periodic dilaton gravity and DSSYK

This paper presents a computer code for analyzing electroweak precision data (EWPD) in the framework of the Standard Model Effective Field Theory (SMEFT), highlights the importance of recent ATLAS and CMS precision measurements, and introduces a novel analysis of the forward–backward asymmetry at the LHC. The computer code provides the likelihood of SMEFT Wilson coefficients based on precision measurements of $\textit{W}$ and $\textit{Z}$ pole observables, interpolation formulas for Standard Model predictions, and modular SMEFT parametrizations. SMEFT predictions including next-to-leading-order (NLO) effects in perturbative and SMEFT expansion are available and five alternative electroweak input parameter schemes are supported. The likelihood addresses shortcomings of previous formulations in the treatment of parametric uncertainties and can be straightforwardly included in SMEFT fits of LHC data. The input parameter scheme dependence and role of NLO corrections is studied for the EWPD fit in the SMEFT. Furthermore, the impact of recent ATLAS and CMS measurements — of the $\textit{W}$ boson mass and width, of the lepton flavour universality (LFU) of $\textit{W}$ branching fractions, and the effective leptonic weak mixing angle, $$ {\sin}^2{\theta}_{\textrm{eff}}^{\ell } $$ — is analyzed. A test of LFU that surpasses the precision of existing measurements is proposed based on the $$ {\sin}^2{\theta}_{\textrm{eff}}^{\ell } $$ measurement. Finally, an ATLAS Drell-Yan triple-differential cross-section measurement is reinterpreted in the SMEFT and combined with the EWPD likelihood. This analysis demonstrates the feasibility of the LFU precision test, improves constraints on muon couplings with respect to the world average, and determines a combination of the quark-coupling asymmetry parameters $\textit{A}$ and $\textit{A}$ with a precision comparable to that of the heavy flavour parameters $\textit{A}$ and $\textit{A}$ .

Hannes Mildner

An EWPD SMEFT likelihood for the LHC — and how to improve it with measurements of W and Z boson properties

We use a non-invertible symmetry to construct a three-zero texture for the down-type quark mass matrix, which can resolve the strong CP problem without invoking the axion, in four-dimensional spacetime with three quark families in QCD. We assume CP invariance at the fundamental high-energy scale.

Japan

Qiuyue Liang

Tsutomu T. Yanagida

Non-invertible symmetry as an axion-less solution to the strong CP problem

In this work we focus on the thermodynamics consistency of a new set of solutions emerging from a cosmology in which dark matter is able to decay into relativistic particles within the dark sector. It is important to stress that the lifetime of dark matter is larger than the age of the universe in order to be consistent with observations. Given that the corresponding decay rate is small, this one can be used as a perturbative parameter and it is possible to construct analytic solutions from a perturbative analysis for the densities of the species and the scale factor. The decay of dark matter is an irreversible process since it occurs out of chemical equilibrium and therefore the entropy per comoving volume increases considerably, as a consequence the temperature does not scale as $$a^{-1}$$ in contrast to an adiabatic expansion. We take into account two scenarios: a) The case in which both species making up the fluid end up in thermal equilibrium and therefore their temperature is the same. b) A second instance in which the species do not reach thermal equilibrium and therefore they have different temperatures. We verify that the second law of thermodynamics is satisfied in any case.

Mexico

Javier Juárez-Jiménez

Ana Avilez-López

Miguel Cruz

Thermodynamics of an universe with decaying cold dark matter

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

We investigate the stability of an intensive plane wave of a massless or light scalar field <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>ϕ</mi></math> in a trilinear scalar model <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>g</mi><mi>ϕ</mi><msup><mi>χ</mi><mn>2</mn></msup></math> due to the resonant production of massive <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>χ</mi></math> particles in a perturbatively forbidden regime. We apply two methods. First, we solve the Heisenberg equation for the quantum amplitudes of the field <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>χ</mi></math> in an external plane wave background, generalizing the solution of Arza [A. Arza, Production of massive bosons from the decay of a massless particle beam, <a href="http://dx.doi.org/10.1103/PhysRevD.105.036004">Phys. Rev. D 105, 036004 (2022)</a>.]. Second, for the light but massive <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>ϕ</mi></math>, we perform the relativistic boost to the rest frame of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>ϕ</mi></math>, reducing the problem to the stability of the thoroughly investigated massive condensate. It turns out that the stability properties are significantly different for the cases of massless and light fields. In the first case, one should adopt the Heisenberg equation approach, since the alternative method cannot provide a comprehensive outcome. In the second case, the use of the Mathieu equation provides a more accurate solution, while for the massless case, this approach is not applicable.

Ekaterina Dmitrieva

Petr Satunin

Tachyonic and parametric resonances for massive particle production in an intense scalar plane wave background

The motion of particles hit by a burst of gravitational waves generated by flyby admits, for the derivative-of-the-Gaussian profile, only a numerical description. The profile can however be approximated by the hyperbolic Scarf potential which admits an exact analytic solution via the Nikiforov-Uvarov method. Our toy model is consistent with the prediction of Zel'dovich and Polnarev provided the wave amplitude takes certain “magical” values.

P.M. Zhang

Z.K. Silagadze

P.A. Horvathy

Flyby-induced displacement effect: An analytic solution