We explore the properties of vector dark matter (DM) particles that predominantly interact with Standard Model (SM) electroweak gauge bosons using an effective field theory approach. The study emphasizes effective contact interactions, invariant under the SM gauge group, between vector DM and SM-neutral electroweak gauge bosons. Focusing on interaction terms up to dimension-eight, we establish constraints on the model parameters based on the observed DM relic density and indirect detection signals. We also examine the prospects for dark matter-nucleon scattering in direct detection experiments. In addition, we analyze the sensitivity of low-energy LEP data to the pair production of light DM particles (with masses up to 80 GeV). Finally, we assess the potential of the proposed International Linear Collider to probe these effective operators through the detection of DM particles produced in association with mono-photons.

India

Hrishabh Bharadwaj

Exploring vector dark matter via effective interactions

We study the new $Z'$ boson as a portal for the production of Higgs bosons $h_0$ and $H_0$ predicted by the Bestest Little Higgs Model through Higgs-strahlung processes $\mu^+\mu^- \to (Z, Z') \to Zh_0, ZH_0$ . We focus on the resonant and nonresonant effects of the $Zh_0, ZH_0$ signals. In our analysis, we consider the center-of-mass energies of $\sqrt{s}=3, 4, 6, 10, 30$ TeV and integrated luminosities of ${\cal{L}}=2, 4, 6, 10, 30$ ${ {\rm{ab}}^{-1}}$ projected for a future muon collider. The possibility of performing precision measurements for Higgs bosons $h_0$ and $H_0$ is very promising for the future muon collider. Furthermore, our results may be useful to the High Energy Physics community. Complementarily, we generate and provide the Feynman rules necessary for studying processes $\mu^+\mu^- \to (Z, Z') \to Zh_0, ZH_0$ .

J.M. Martínez-Martínez

A. Gutiérrez-Rodríguez

E. Cruz-Albaro

M.A. Hernández-Ruíz

New $\textit{Z}$' boson of the bestest little Higgs model as a portal to signatures of Higgs bosons $\textit{h}$ $_{0}$ and $\textit{H}$ $_{0}$ at the future muon collider

This paper is motivated by the application of the inverse isoperimetric inequality to establish constraints on the parameters of gravity’s rainbow. We investigate the thermodynamic (in)stability conditions for $\textit{d}$-dimensional energy-dependent black holes, which are recognized as $\textit{d}$-dimensional black holes within the framework of gravity’s rainbow. To achieve this, we calculate thermodynamic quantities such as Hawking temperature, entropy, total mass, and heat capacity in both extended and non-extended phase spaces for these black holes. We assess the physical and stable regions by utilizing these thermodynamic quantities alongside the inverse isoperimetric inequality, aiming to determine constraints on the rainbow functions. Finally, we show that by considering a constraint on the rainbow function, these black holes satisfy the super-entropic condition.

Iran

Behzad Panah

Narges Heidari

Mana Soleimani

Maryam Kaveh

Super-entropic black holes in gravity’s rainbow and determining constraints on rainbow functions

For a 3d gauged linear sigma model parametrized by a Kähler manifold $\textit{X}$, the 3d BPS index defines a $\textit{q}$-series that can be analytically continued in the Kähler modulus by standard methods. It is argued that an SL(2$\textit{,}$ ℤ)-transform of the Birkhoff connection matrix captures non-perturbative corrections to the 3d GLSM. As an application, a 3d lift of the standard 2d GLSM for the resolved conifold is shown to provide a world-volume dual for the non-perturbative topological string on the resolved conifold. The perturbative 3d BPS index computes the Gopakumar-Vafa partition function, while the analytic continuation matches existing proposals for a non-perturbative completion of the topological string.

Germany

Hans Jockers

Non-perturbative corrections to 3d BPS indices and topological strings

Relative entropy is a non-negative quantity and offers a powerful means of achieving a unified understanding of fundamental properties in physics, including the second law of thermodynamics and positivity bounds on effective field theories (EFTs). We analyze the relative entropy in scalar field theories and show that the non-negativity of relative entropy is potentially violated in perturbative calculations based on operator and loop expansions. Conversely, this suggests that the consistency of the EFT description in the scalar field theory can be identified by the sign of the relative entropy. In fact, we revisit an EFT of single-field inflation and present a relation between its non-linear parameter $\textit{f}$ and the consistency condition of the EFT description derived from the relative entropy method. We find that interesting regions of $\textit{f}$ that are observationally allowed can be constrained from the relative entropy by imposing the consistency of the EFT description when the EFT is generated via the interaction with heavy fields in UV theories.

Israel

Switzerland

Daiki Ueda

Japan

Kazuhiro Tatsumi

Consistency of EFT illuminated via relative entropy: a case study in scalar field theory

In this work, we study the mass spectrum of the hidden-charm hybrid states with the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>J</mi><mrow><mi>P</mi><mi>C</mi></mrow></msup><mo>=</mo><msup><mn>0</mn><mrow><mo>−</mo><mo>+</mo></mrow></msup></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mn>0</mn><mrow><mo>+</mo><mo>+</mo></mrow></msup></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mn>0</mn><mrow><mo>−</mo><mo>−</mo></mrow></msup></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mn>1</mn><mrow><mo>+</mo><mo>+</mo></mrow></msup></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mn>1</mn><mrow><mo>+</mo><mo>−</mo></mrow></msup></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mn>1</mn><mrow><mo>−</mo><mo>+</mo></mrow></msup></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mn>1</mn><mrow><mo>−</mo><mo>−</mo></mrow></msup></math>, <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mn>2</mn><mrow><mo>−</mo><mo>+</mo></mrow></msup></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mn>2</mn><mrow><mo>+</mo><mo>+</mo></mrow></msup></math> via the quantum chromodynamics (QCD) sum rules in a consistent way. We calculate the vacuum condensates up to dimensions-6 by taking account of both the leading order and next-to-leading order contributions, and take the energy scale formula <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>μ</mi><mo>=</mo><msqrt><mrow><msubsup><mrow><mi>M</mi></mrow><mrow><mi>X</mi><mo>/</mo><mi>Y</mi><mo>/</mo><mi>Z</mi></mrow><mrow><mn>2</mn></mrow></msubsup><mo>−</mo><mo stretchy="false">(</mo><mn>2</mn><msub><mrow><mi mathvariant="double-struck">M</mi></mrow><mrow><mi>c</mi></mrow></msub><msup><mrow><mo stretchy="false">)</mo></mrow><mrow><mn>2</mn></mrow></msup></mrow></msqrt></mrow></math> to choose the suitable energy scales of the QCD spectral densities, it is the first time to explore the energy scale dependence of the QCD sum rules for the hidden-charm hybrid states.

China

Zhi-Gang Wang

Mass spectrum of the hidden-charm hybrid states via QCD sum rules

In this work, we critically reanalyze the explicit breaking of the Peccei-Quinn global symmetry—and the corresponding corrections to the QCD axion potential—induced by gravity. Specifically, we examine the role of gravitational instantons, which are nonperturbative, finite-action solutions to the Euclidean Einstein equations. These instantons represent topologically nontrivial configurations of spacetime and are analogous to instantons in gauge theory. The amount of symmetry breaking induced by gravitational instantons can be computed in a controlled way within the framework of semiclassical gravity, using ’t Hooft operators, in full analogy to the computation of the axion potential arising from QCD small instanton effects. Contrary to previous results in the literature, we find that the effects of gravitational instantons are extremely small and therefore do not give rise to a significant quality problem for the axion solution to the strong <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>C</mi><mi>P</mi></mrow></math> problem, both within the Standard Model and in beyond-the-Standard-Model scenarios that involve multiple copies of the Standard Model. In conclusion, we argue that, assuming the ultraviolet completion of gravity is weakly coupled, the axion solution to the strong <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi>C</mi><mi>P</mi></mrow></math> problem remains free from any quality issues due to gravity. Along the way, we derive the effective Lagrangian of the QCD axion, including its gravitational coupling.

Italy

Pier Giuseppe Catinari

Alfredo Urbano

Gravitational instantons and the quality problem of the QCD axion: Facts, speculations, and statements in between

When a gravitational wave (GW) passes through a dc magnetic field, it couples to the conducting wires carrying the currents which generate the magnetic field, causing them to oscillate at the GW frequency. The oscillating currents then generate an ac component through which the GW can be detected—thus forming a resonant mass detector or a nagnetic Weber bar. We quantify this claim and demonstrate that magnets can have exceptional sensitivity to GWs over a frequency range demarcated by the mechanical and electromagnetic resonant frequencies of the system; indeed, we outline why a magnetic readout strategy can be considered an optimal Weber bar design. The concept is applicable to a broad class of magnets, but can be particularly well exploited by the powerful magnets being deployed in search of axion dark matter, for example, by DMRadio and ADMX-EFR. Explicitly, we demonstrate that the MRI magnet that is being deployed for ADMX-EFR can achieve a broadband GW strain sensitivity of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo>∼</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>20</mn></mrow></msup><mo>/</mo><msqrt><mi>Hz</mi></msqrt></math> from a few kHz to about 10 MHz, with a peak sensitivity down to <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo>∼</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>22</mn></mrow></msup><mo>/</mo><msqrt><mi>Hz</mi></msqrt></math> at a kHz exploiting a mechanical resonance.

CERN

Valerie Domcke

Sebastian A.R. Ellis

United States

Nicholas L. Rodd

Magnets are Weber Bar Gravitational Wave Detectors

We investigate the low energy regime of BFSS quantum mechanics using its holographic dual. We identify three distinct thermodynamic phases (black holes) and analyze their thermodynamic properties extensively, including phase transitions amongst the several phases. While the properties of the canonical ensemble aligns with existing conjectures on BFSS thermodynamics, we uncover intriguing and unexpected behavior in the microcanonical ensemble. Specifically, for sufficiently low energies, we observe the dominance of the localized phase. Surprisingly, we also identify an energy range where the non-uniform phase becomes dominant. The transition between these phases is mediated by a Kol-type topology-changing phenomenon.

United Kingdom

Óscar J.C. Dias

Jorge E. Santos

Low Energy Limit of Banks-Fischler-Shenker-Susskind Quantum Mechanics

Motivated by a new term-wise factorised formula for the two-loop MHV integrand for scattering amplitudes in $$ \mathcal{N} $$ = 4 super Yang-Mills (SYM), together with recent results for the five-point negative ladders in loop space, we present the canonical forms for general ladders in loop space for an arbitrary number of particles to all loops. We make use of the graphical notation introduced in the negative geometries literature, where each loop momentum is represented as a vertex, and mutual positivity (resp. negativity) conditions as a positive (resp. negative) edge. In this paper we extend this notation to include the notion of chambers of the one-loop momentum amplituhedron. Equipped with this new graphical notation, we find the canonical form of the $\textit{L}$-loop (negative/positive) ladders for all MHV amplitudes. Our final formula is remarkably simple and reminiscent of the chiral pentagon expansion of the one and two loop momentum amplituhedron. It expresses ladder contributions as sums over maximal cuts, with each term appearing in the sum factorising into products of either chiral pentagons or their simple generalisations.

Ross Glew

Tomasz Łukowski

Positive and negative ladders in loop space