Mon·Nov 3, 2025Monday·November 3, 2025

1. 01*

   Electromagnetic tomography of spin-$\frac{3}{2}$ hidden-charm strange pentaquarks

   Ulaş Özdem🇹🇷

   Understanding how quarks are spatially arranged inside exotic pentaquarks remains one of the key open problems in contemporary hadron spectroscopy. The electromagnetic multipole moments of hadrons provide a direct probe of their internal quark--gluon geometry and spatial charge distributions. Motivated by this, we employ QCD light-cone sum rules to compute the magnetic dipole, electric quadrupole, and magnetic octupole moments of the $J^P=3/2^{-}$ pentaquark with strangeness $S=-1$. Five distinct diquark--diquark--antiquark interpolating currents are constructed to explore possible internal configurations. The resulting electromagnetic moments exhibit pronounced sensitivity to the underlying quark arrangement: magnetic dipole moments range from $-2.28{\mu }_N$ to $+3.36{\mu }_N$, establishing this observable as a key discriminator among configurations with identical quantum numbers. Nonzero electric quadrupole and magnetic octupole moments indicate clear deviations from spherical symmetry, while a detailed decomposition shows that light quarks dominate the magnetic response and the charm quark drives quadrupole deformation. These findings position electromagnetic multipole moments as quantitative and discriminating probes of exotic hadron structure, providing concrete benchmarks for forthcoming LHCb, Belle II, and lattice QCD studies.

   hep-phhep-exhep-latJHEP(2026)·9 citations
2. 02*

   Long-Lived HNLs via ALP Portal at the LHC

   Rebeca Beltrán🇪🇸 · Chandan Hati🇪🇸 · Martin Hirsch🇪🇸 · Ana Martín-Galán🇪🇸

   Heavy neutral leptons (HNLs) and axion-like particles (ALPs) are both considered well-motivated candidates for beyond the standard model (BSM) physics. If ALPs with sizable couplings to gluons exist, they will be abundantly produced at the LHC. Therefore, HNLs produced via the ALP portal may provide unprecedented sensitivities to HNL parameters. Here, we study the prospects for the high-luminosity LHC to search for long-lived HNLs. We consider future far detectors as well as ATLAS in our simulations. In the limit where the ALP mass is above the TeV scale, HNLs are effectively produced by a dimension-8 operator connecting HNL pairs to gluons. For completeness, we therefore also calculate future LHC sensitivities for HNLs produced via $N_R$SMEFT operators with gluons.

   hep-phJHEP(2026)·3 citations
3. 03*

   Spectra of light and heavy mesons with $J\le 5$ in a relativistic Bethe-Salpeter approach

   Stephan Hagel🇩🇪 · Christian S. Fischer🇩🇪 · Markus Q. Huber🇩🇪 · Jonathan Y. Yigzaw🇩🇪

   We extend the range of application of the relativistic Dyson-Schwinger/Bethe-Salpeter approach from previously discussed mesons with total angular momentum $J\le 3$ to the ones with $J=4,5$. On a technical level, the new element is the general Dirac tensor representations for the latter which, to our knowledge, are presented here for the first time. As a first application, we provide an exploratory spectrum for these mesons in a rainbow-ladder truncation of Dyson-Schwinger and Bethe-Salpeter equations. We discuss the merits and limitations of this truncation and explore the shape of the heavy-quark potential corresponding to the underlying effective running coupling. With our predictions for the masses of ground state mesons with quantum numbers $J^{PC}=3^{--},4^{++},5^{--}$ we identify Regge trajectories in channels where the interaction model can be trusted on a semi-quantitative level. In other channels, discrepancies with experiments confirm the well-known need to go beyond rainbow-ladder in the Dyson-Schwinger/Bethe-Salpeter approach by using more sophisticated interactions.

   hep-phEPJA(2026)·5 citations
4. 04*

   Improved phenomenology of $\pi N$ transition distribution amplitudes

   Bernard Pire🇫🇷 · Kirill Semenov-Tian-Shansky🇰🇷 · Paweł Sznajder🇵🇱 · Lech Szymanowski🇵🇱

   To study cross sections and polarization asymmetries for the processes $ep\to en{\pi }^{+}$ and $ep\to ep{\pi }^0$ in the backward region, we develop a flexible phenomenological model for nucleon-to-pion transition distribution amplitudes ($\pi N$ TDAs), which are used in the QCD collinear factorization description of the scattering amplitudes. Our model is based on the two-component factorized Ansatz for the corresponding spectral densities, quadruple distribution. It takes into account the constraints for $\pi N$ TDAs arising from the threshold pion production theorem and also includes a forward limit contribution that can be fitted to experimental data. We examine the sensitivity of observable predictions to various modelling assumptions.

   hep-phhep-exnucl-exnucl-thEPJ Web Conf.(2026)·1 citation
5. 05*

   Classifying extended Higgs models through the trilinear Higgs boson coupling measurement at future colliders

   Nagisa Hiroshima🇯🇵 · Mitsuru Kakizaki🇯🇵 · Shuhei Ohzawa

   We investigate the trilinear Higgs boson coupling derived from the functional forms of various extended Higgs potentials. In light of experimental constraints on Higgs boson couplings, we focus on extended Higgs models in which the trilinear Higgs boson coupling is predominantly determined by the Standard Model (SM) Higgs field. Such models include the nearly aligned Higgs effective field theory, classically scale-invariant models, pseudo-Nambu-Goldstone boson scenarios, tadpole-induced models, and others. We also consider higher-order corrections, including top quark and new particle contributions that are often neglected, and discuss their impact on the trilinear Higgs boson coupling. Finally, we show to what extent the functional forms of the Higgs potentials can be probed at future colliders.

   hep-phPTEP(2026)·0 citations
6. 06*

   Infrared singularities of multileg amplitudes with a massive particle at three loops

   Einan Gardi🇬🇧 · Zehao Zhu🇬🇧

   We determine the complete three-loop QCD soft anomalous dimension for multileg amplitudes involving a single massive coloured particle and any number of massless ones. This is achieved by applying a novel strategy based on a lightcone expansion of correlators of semi-infinite Wilson lines using the method of regions. The resulting region integrals depend exclusively on rescaling-invariant ratios that remain finite in the limit. We evaluate these integrals using differential equation techniques. The result is written in terms of uniform weight five generalised polylogarithms of a twelve letter alphabet in three variables, and is compatible with the massless limit as well as with two- and three-particle collinear factorization.

   hep-phhep-thPRL(2026)·8 citations
7. 07*

   CMB observables and reheat temperature as a window to models of inflation and freeze-in dark matter production

   Anish Ghoshal🇵🇱 · Paweł Kozów🇵🇱 · Marek Olechowski🇵🇱 · Stefan Pokorski🇵🇱

   A systematic approach is presented for using CMB observables and reheating temperature for discriminating between various models of inflation and certain freeze-in dark matter scenarios. It is applied to several classes of $\alpha$-attractor models as an illustrative example. In the first step, all independent parameters of the inflationary potential are expressed in terms of the CMB observables (the three parameters - by the scalar spectral index $n_s$, scalar amplitude $A_s$ and the tensor-to-scalar amplitude ratio $r$). For a standard reheating mechanism characterized by the inflaton equation of state parameter $w$ and its effective dissipation rate $\Gamma$ the reheating temperature is uniquely fixed in terms of the CMB observables measured for some pivot scale $k_{\ast }$. There are striking consequences of this fact. The model independent bounds on the reheating temperature, the BBN lower bound and the upper bound of the order of the GUT/Planck scale, translate themselves for each class of models into very narrow ranges of the allowed values of the spectral index $n_s(k_{\ast })$, providing their strong tests by the present and future CMB data. The recent tension between Planck and DESI-ACT results has strong impact on our conclusions. Furthermore, given a class of inflaton models satisfying those tests, the reheating temperature is an interesting portal to link the CMB observables to the particle physics scenarios that are sensitive to it. As an example, non-thermal dark matter (DM) production mechanisms are discussed. One obtains then a consistency check between theories of inflation and DM production. If the future precision of the CMB data will constrain the reheating temperature beyond the model independent bounds, further constraints on the DM production will follow.

   hep-phastro-ph.CO7 citations
8. 08*

   From photons to dikaon -- theoretical insights into $K^{+}{K}^{-}$ production in nuclear collisions

   Nikhil Krishna🇵🇱 · Mariola Klusek-Gawenda🇵🇱 · Antoni Szczurek🇵🇱

   The production of charged kaon pairs in ultraperipheral heavy-ion collisions can proceed via photoproduction (gamma-Pomeron interaction) or via photon-photon fusion. An important contribution to this process arises from the decays of scalar, tensor and vector mesons. This study provides a consistent description of K+K- production at both the elementary level (gamma gamma -> meson -> K+K-) and the nuclear level (Pb Pb -> Pb Pb K+K-). The gamma gamma fusion cross section is compared with experimental results from Belle, TPC/Two-Gamma and ARGUS. A comparison with existing midrapidity measurements is presented, together with theoretical predictions for ultraperipheral Pb-Pb collisions at sqrt(sNN) = 5.02 TeV.

   hep-ph0 citations
9. 09*

   Beyond Leading Logarithms in $g_V$: The Semileptonic Weak Hamiltonian at $\mathcal{O}(\alpha {\alpha }_s^2)$

   Francesco Moretti🇩🇪 · Martin Gorbahn🇬🇧 · Sebastian Jaeger🇬🇧

   We present the first next-to-leading-logarithmic QCD analysis of the electromagnetic corrections to the semileptonic weak Hamiltonian, including the mixed $\mathcal{O}(\alpha {\alpha }_s^2)$ corrections to the vector coupling $g_V$. The analysis combines the evaluation of three-loop anomalous dimensions and two-loop matching corrections with a consistent factorization of short-distance QCD effects. The latter is implemented through a scheme change based on a $d$-dimensional operator product expansion performed inside the loop integrals. The resulting renormalization-group--improved expression for the radiative correction ${\Delta }_R^V=2.436(16)\%$ can be systematically refined using input from lattice QCD and perturbation theory and improves the consistency of first-row CKM unitarity tests.

   hep-phhep-latnucl-th14 citations
10. 10*

    Soft Gravitons, Hard Truths: Infrared Safety of Particle Processes in a Gravitational-Wave Background

    Wen-Yuan Ai🇦🇹 · Sebastian A. R. Ellis🇬🇧 · Josef Pradler🇦🇹

    Gravitational waves are thought to propagate unattenuated through matter due to a cancellation between graviton absorption and stimulated emission inferred from leading-order soft-graviton arguments. We revisit this reasoning and show that it fails for the converse problem: the effect of a gravitational-wave background on matter. For unstable particles, real graviton emission \emph{and} absorption appear to enhance decay rates. By extending the soft-graviton framework describing real and virtual processes in a gravitational wave background, and resumming them to all orders, we show that inclusive decay rates remain essentially unchanged. The mutual transparency between matter and gravitational radiation thus follows from infrared safety, and not from a fortuitous cancellation in the lowest-order approximation of exclusive rates.

    hep-phhep-th5 citations
11. 11*

    WallGo investigates: Theoretical uncertainties in the bubble wall velocity

    Jorinde van de Vis🇨🇭 · Philipp Schicho🇨🇭 · Lauri Niemi🇫🇮 · Benoit Laurent🇨🇦 · Joonas Hirvonen🇬🇧 · Oliver Gould🇬🇧

    We examine theoretical uncertainties in state-of-the-art calculations of the bubble wall velocity during first-order cosmological phase transitions. By utilising the software WallGo for two extensions of the Standard Model, we find several $O(1)$ uncertainties arising from the number of particles taken out of equilibrium, the logarithmically and power enhanced collision integrals, the treatment of thermal masses, the nucleation temperature, the $\tanh$ ansatz, and the perturbative order of the effective potential. However, we show that the linearisation of the Boltzmann equations is generally a good approximation with much smaller associated errors. We further clarify the limitations of the quasiparticle approximation in regions with negative mass squared. This study provides a detailed uncertainty budget and highlights where future efforts should be directed to improve the reliability of wall velocity and hence gravitational wave predictions.

    hep-phastro-ph.COJHEP(2026)·25 citations
12. 12*

    Rydberg Single Photon Detection for Probing 0.1-10 meV Dark Matter with BREAD

    Abhishek Banerjee🇺🇸 · Reza Ebadi🇺🇸 · Surjeet Rajendran🇺🇸

    We introduce a Rydberg-based single photon detector (SPD) for probing dark matter in the 0.1-10 meV mass range (20 GHz-2 THz). The Rydberg SPD absorbs photons produced and focused by the BREAD dish antenna and trades them for free, detectable electrons. At the lower end of the mass range, photons drive Rydberg-Rydberg transitions, which are read out via state-selective ionization. At higher masses, they directly ionize the Rydberg atoms.

    hep-phastro-ph.COquant-phPRD(2026)·5 citations
13. 13*

    Energy Correlators from Partons to Hadrons: Unveiling the Dynamics of the Strong Interactions with Archival ALEPH Data

    Hannah Bossi🇺🇸 · Yi Chen🇺🇸 · Yu-Chen Chen🇺🇸 · Max Jaarsma🇳🇱 · Yibei Li🇩🇪 · Jingyu Zhang🇺🇸 · Ian Moult🇺🇸 · Wouter Waalewijn🇳🇱 · Hua Xing Zhu🇨🇳 · Anthony Badea🇺🇸 · Austin Baty🇺🇸 · Christopher McGinn🇺🇸 and 3 other authors

    Quantum Chromodynamics (QCD) is a remarkably rich theory exhibiting numerous emergent degrees of freedom, from flux tubes to hadrons. Their description in terms of the underlying quarks and gluons of the QCD Lagrangian remains a central challenge of modern physics. Colliders offer a unique opportunity to probe these phenomena experimentally: high energy partons produced from the QCD vacuum excite these emergent degrees, imprinting their dynamics in correlations in asymptotic energy flux. Decoding these correlations requires measurements with exceptional angular resolution, beyond that achieved in previous measurements. Recent progress has enabled precision calculations of energy flux on charged particles alone, allowing data-theory comparisons for measurements using high resolution tracking detectors. In this Letter, we resurrect thirty-year-old data from the ALEPH tracker, and perform a high angular resolution measurement of the two-point correlation of energy flux, probing QCD over three orders of magnitude in scale in a single measurement. Our measurement unveils for the first time the full spectrum of the correlator, including light-ray quasi-particle states, flux-tube excitations, and their transitions into confined hadrons. We compare our measurement with record precision theoretical predictions, achieving percent level agreement, and revealing interesting new phenomena in the confinement transitions. More broadly, we highlight the immense potential of this newly unlocked archival data set, the so called "recycling frontier", and emphasize synergies with ongoing and future collider experiments.

    hep-phhep-exhep-thnucl-ex+133 citations
14. 14*

    Symmetry-Protected $\alpha$-Attractor Hybrid Inflation in Supergravity and Constraints from ACT DR6 and DESI DR2

    Swapnil Kumar Singh🇮🇳

    We present a symmetry-protected supergravity effective realization of hybrid $\alpha$-attractor inflation with a sequestered Stückelberg uplift. The model contains four chiral multiplets, an inflaton modulus $T$, a stabilizer field $S$, and a pair of oppositely charged waterfall multiplets $(\Psi ,\bar{\Psi })$, together with a hidden Stückelberg $U(1{)}_D$ sector that generates an approximately constant positive contribution to the scalar potential. Along the real inflationary trajectory, the F-term potential realizes the E-model plateau \[ U(\phi)=V_0\left(1-e^{-\sqrt{2/(3\alpha)}\,\phi}\right)^2 , \] while the sequestered uplift shifts the total energy density without directly modifying the tree-level inflaton slope. We derive the background evolution, the analytic $N$--$\varphi$ relation, the waterfall stability condition, and the leading predictions for the scalar spectral index and tensor-to-scalar ratio. The model retains the characteristic red-tilted $\alpha$-attractor behavior, with $n_s\simeq 1-2/N_{\ast }$ and tensor amplitudes controlled primarily by the curvature parameter $\alpha$, while the uplift and the hybrid end point generate only subleading corrections at fixed $N_{\ast }$. We also discuss the assumptions required for an effectively single-field trajectory, including the treatment of the light angular component of $T$, and examine the sensitivity of the sequestered uplift to Planck-suppressed cross-couplings. The resulting construction provides a controlled supergravity embedding of hybrid $\alpha$-attractor inflation compatible with current CMB constraints, including Planck, ACT DR6, and DESI DR2, while remaining testable by future $B$-mode searches such as LiteBIRD and CMB-S4.

    hep-phastro-ph.COPhys.Dark Univ.(2026)·9 citations
15. 15*

    Lattice Calculation of Light Meson Radiative Leptonic Decays

    Peter Boyle🇺🇸 · Norman H. Christ🇺🇸 · Xu Feng🇨🇳 · Taku Izubuchi🇺🇸 · Luchang Jin🇺🇸 · Christopher T. Sachrajda🇬🇧 · Xin-Yu Tuo🇺🇸

    In this work, we perform a lattice QCD calculation of the branching ratios and the form factors of radiative leptonic decays $P\to \ell {\nu }_{\ell }\gamma$ ($P=\pi ,K$) using $N_f=2+1$ domain wall fermion ensembles generated by the RBC and UKQCD collaborations at the physical pion mass. We adopt the infinite volume reconstruction (IVR) method, which extends lattice data to infinite volume and effectively controls the finite volume effects. This study represents a first step toward a complete calculation of radiative corrections to leptonic decays using the IVR method, including both real photon emissions and virtual photon loops. For decays involving a final state electron, collinear radiative corrections, enhanced by the large logarithmic factors such as $\ln (m_{\pi }^2/m_e^2)$ and $\ln (m_K^2/m_e^2)$, can reach the level of $O(10\%)$ and are essential at the current level of theoretical and experimental precision. After including these corrections, our result for $\pi \to e{\nu }_e\gamma$ agrees with the PIBETA measurement; for \(K \to e\nu_e\gamma\), our results are consistent with the KLOE data and exhibit a $1.7\sigma$ tension with E36; and for $K\to \mu {\nu }_{\mu }\gamma$, where radiative corrections are negligible, our results confirm the previously observed discrepancies between lattice results and the ISTRA/OKA measurements at large photon energies, and with the E787 results at large muon photon angles.

    ↳ hep-lathep-exhep-phPRD(2026)·5 citations
16. 16*

    $Q$-ball superradiance: Analytical approach

    Guo-Dong Zhang🇨🇳 · Shuang-Yong Zhou🇨🇳 · Meng-Fan Zhu🇨🇳

    It was recently discovered that waves scattering off a $Q$-ball can extract energy from it. We present an analytical treatment of this process by adopting a multi-step function approximation for the background field, which yields perturbative solutions expressed in terms of Bessel functions. For thin-wall $Q$-balls, the amplification factors reduce to simple sinusoidal functions, which explains the multi-peak structure of the spectrum and identifies the physical quantities that determine it. For instance, at high frequencies, the peak spacing is simply the inverse of the $Q$-ball size. The analytical solution further enables us to delineate the full range of possible amplification factors. For general $Q$-balls, this analytical framework also substantially improves the efficiency of evaluating the amplification factors.

    ↳ hep-thgr-qchep-phPRD(2026)·4 citations
17. 17*

    Conditional variational autoencoders for cosmological model discrimination and anomaly detection in cosmic microwave background power spectra

    Tian-Yang Sun🇨🇳 · Tian-Nuo Li🇺🇸 · He Wang🇨🇳 · Jing-Fei Zhang🇺🇸 · Xin Zhang🇺🇸

    The cosmic microwave background power spectra are a primary window into the early universe. However, achieving interpretable compression and fast inference diagnostics under weak model assumptions remains challenging. We propose a parameter-conditioned variational autoencoder (CVAE) that aligns a data-driven latent representation with cosmological parameters while retaining an interface to likelihood-style diagnostic tests. The model achieves high directional reconstruction fidelity for the $D_{\ell }^{TT}$, $D_{\ell }^{EE}$, and $D_{\ell }^{TE}$ spectra in just 5 latent dimensions. It reconstructs spectra for several beyond-$\Lambda$CDM test cases, including controlled parameter extrapolations, and enables an amortized surrogate diagnostic that reduces one representative post-training MCMC run from $\sim$40 hours on CPU cores to $\sim$2 minutes on a GPU in this demonstration. The learned latent space shows a distributed, partially structured organization that mirrors known cosmological parameters and their degeneracies. It also provides representation-space discrimination diagnostics for distinguishing tested cosmological spectra from a fiducial reference. Overall, this physics-informed CVAE supports interpretable compression, rapid diagnostic exploration, and anomaly-sensitive representation learning beyond $\Lambda$CDM.

    ↳ astro-ph.COastro-ph.IMgr-qchep-phPRD(2026)·5 citations
18. 18*

    Constraints on Axion-photon coupling from the Global 21-cm Signal

    Hao Jiao🇨🇦

    A radiation field can be excited via parametric resonance when an oscillating axion field couples to the electromagnetic sector through a Chern-Simons interaction. As demonstrated in previous works, this mechanism can generate primordial magnetic fields shortly after recombination and provide sufficient ultraviolet radiation for the formation of direct collapse black holes (DCBHs). In this study, I analyze constraints on the parametric resonance scenario from global 21cm observations. I find that there exist viable regions in the parameter space that satisfy both observational limits and the physical requirements of the magnetic field and DCBH formation scenarios.

    ↳ astro-ph.COastro-ph.GAhep-phhep-th0 citations
19. 19*

    Pseudo-Hermitian QFT: relativistic scattering and symmetry structure

    Ruifeng Leng🇨🇳 · Cheng-Yang Lee🇨🇳 · Siyi Zhou🇨🇳

    Unitarity is a cornerstone of quantum theory, ensuring the conservation of probability and information. Although non-Hermitian Hamiltonians are typically associated with open or dissipative systems, pseudo-Hermitian quantum mechanics shows that real spectra and unitary evolution can still emerge through a suitably defined inner product. Motivated by this insight, we extend the pseudo-Hermitian framework to relativistic quantum field theory and construct a consistent formulation of scattering processes. A novel structural feature of this theory is the presence of distinct metric operators for the in and out sectors, connected through a nontrivial metric projector that guarantees global probability conservation under pseudo-unitary time evolution. We further develop a general symmetry formalism, showing that each symmetry generally corresponds to two pseudo-unitary operators associated with the in and out metrics, respectively. Within this framework, the scattering matrix admits a perturbative expansion through the Dyson series and remains Lorentz invariant and unitary, remarkably in complete agreement with the conventional Hermitian case. The fundamental CPT theorem is also shown to hold. Our results provide a rigorous foundation for interacting pseudo-Hermitian quantum field theories and open new directions for exploring their possible physical implications beyond the standard Hermitian paradigm.

    ↳ hep-thhep-ph1 citation
20. 20*

    Earth-lens telescope for distant axion-like particle sources with stimulated backward reflection

    Taiyo Nakamura🇯🇵 · Kensuke Homma🇯🇵

    We propose a novel telescope concept based on Earth's gravitational lensing effect, optimized for the detection of distant dark matter sources, particularly axion-like particles (ALPs). When a unidirectional flux of dark matter passes through Earth at sufficiently high velocity, gravitational lensing can concentrate the flux at a distant focal region in space. Our method combines this lensing effect with stimulated backward reflection (SBR), arising from ALP decays that are induced by directing a coherent electromagnetic beam toward the focal point. The aim of this work is to numerically analyze the structure of the focal region and to develop a framework for estimating the sensitivity to ALP-photon coupling via this mechanism. Numerical calculations show that, assuming an average ALP velocity of 520,km/s -- as suggested by the observed stellar stream S1 -- the focal region extends from $9\times 10^9$,m to $1.4\times 10^{10}$,m, with peak density near $9.6\times 10^9$,m. For a conservative point-like ALP source located approximately 8,kpc from the solar system, based on the S1 stream, the estimated sensitivity in the eV mass range reaches $g/M=\mathcal{O}(10^{-22}),{\mathrm{GeV}}^{-1}$. This concept thus opens a path toward a general-purpose, space-based ALP observatory that could, in principle, detect more distant sources -- well beyond $\mathcal{O}(10),\mathrm{kpc}$ -- provided that ALP-photon coupling is sufficiently strong, that is, $M\ll M_{\mathrm{Planck}}$.

    ↳ astro-ph.COhep-phUniverse(2025)·1 citation
21. 21*

    Extracting Properties of Dark Dense Environments around Black Holes from Gravitational Waves

    Qianhang Ding🇰🇷 · Minxi He🇰🇷 · Hui-Yu Zhu🇰🇷

    Dark matter (DM) can form dense condensates around black holes (BHs), such as superradiant clouds and ultracompact mini halos, which can significantly affect the orbital evolution of their companion objects through dynamical friction (DF). In this work, we define a novel quantity to quantify such effects in the emitted gravitational waves (GWs) in terms of GW amplitude, frequency, and their time derivatives. The information about the density profile can be extracted from this quantity, which characterizes the type of condensate and, therefore, the corresponding DM property. This quantity allows us to probe the dark dense environment by multi-wavelength GW observation with existing ground-based and future space-based GW detectors, potentially revealing the properties of the dark sector and shedding light on the primordial origin of the stellar mass BHs. A null detection can place strong constraints on the relevant DM parameters.

    ↳ gr-qcastro-ph.COastro-ph.HEhep-phPRD(2026)·4 citations
22. 22*

    Spectrum of the SU(2) scalar-fermion-gauge system under the influence of the Brout-Englert-Higgs effect

    Georg Wieland🇦🇹 · Axel Maas🇦🇹

    Gauge invariance requires physical states to be composite, even in the weak sector of the Standard Model (SM). The Fröhlich-Morchio-Strocchi (FMS) mechanism resolves this subtlety and predicts additional Higgs contributions in SM processes. While this has been supported by theoretical investigations in the bosonic sector, its impact on fermionic observables remains largely unexplored. We use non-perturbative lattice techniques within a gauge-invariant framework to study a proxy theory of the weak sector with dynamical fermions. We determine the physical spectrum of the theory and interpret the results in the context of the FMS mechanism. Additionally, we identify suitable simulation points for a scattering analysis as a first step toward cross-sections relevant to (future lepton) colliders.

    ↳ hep-lathep-phPoS(2026)·1 citation
23. 23*

    Holographic equation of state matched with hadron gas equation as a tool for the study of the quark-gluon plasma evolution

    A.V. Anufriev🇷🇺 · V.N. Kovalenko🇷🇺

    In this paper, we discuss the matching of the holographic equation of state with the equation of Hadron Resonance Gas for studying the nuclear matter properties within the framework of relativistic heavy-ion collisions. Machine learning methods are applied to the calibration of model's free parameters using the lattice QCD results for the physical values of quark masses. One of the most advanced procedures for matching is used with the function that approximate behavior of both models on particular limit adopted from NEOS equation. Final hadronic spectra are obtained within multi-staged numerical approach of the iEBE-MUSIC and SMASH-vHLLE packages. The code of relativistic hydrodynamics is modified by implementing a tabulated holographic equation of state, enabling simulations of quark-gluon plasma evolution with dynamically generated initial conditions via the 3D Monte Carlo Glauber Model and SMASH. Hybrid iSS+UrQMD and Hadron Sampler+SMASH approaches are utilized at the freeze-out stage.

    ↳ nucl-thgr-qchep-phhep-thTheor.Math.Phys.(2026)·0 citations
24. 24*

    String-induced vacuum decay and its gravitational wave signatures

    Aleksandr Chatrchyan🇸🇪 · Florian Niedermann🇸🇪 · Phoebe Richman-Taylor🇮🇸

    False vacuum decay typically proceeds via the nucleation of spherical bubbles of true vacuum, described by $O(4)$ symmetric field configurations in Euclidean time. In this work, we investigate how the presence of cosmic strings can catalyze the decay process. To this end, we consider a complex scalar field charged under a global or local $U(1)$ symmetry. Assuming a non-trivial vacuum manifold, realizable for example in a simple sextic potential, we derive relativistic bounce solutions with $O(2)\times O(2)$ symmetry, corresponding to elongated bubbles seeded by a cosmic string of the same scalar field. Building up on earlier results in the literature, we identify the region of parameter space where vacuum decay predominantly proceeds via this alternative channel, thereby providing an explicit mechanism for the quantum decay of cosmic strings. Finally, we present an initial discussion of the gravitational wave signal associated with this type of vacuum decay and its possible connection to the recently observed stochastic signal in pulsar timing arrays.

    ↳ astro-ph.COhep-phhep-thPRD(2026)·6 citations
25. 25*

    Production of Gravitational Waves from Preheating and Tachyonic Instabilities

    Khursid Alam🇮🇳 · Koushik Dutta🇮🇳 · Ahamadullah Khan🇺🇸

    We analyze GW production during preheating for an $\alpha$-attractor potential terminating in the positive-curvature regime, with energy transfer via $\varphi {\chi }^2$. Linear Floquet analysis and nonlinear simulations show that $\varphi$ fluctuations grow by parametric resonance, while $\chi$ undergoes tachyonic bursts. The GW spectrum features two peaks: a dominant low-frequency peak from the parametric channel and a subdominant high-frequency peak from the tachyonic channel. Redshifted to today, the peak reaches $h^2{\Omega }_{\mathrm{GW}}^{(0)}\sim 10^{-11}$ at $f_p^{(0)}\sim 10^7$ Hz. This multi-peak structure is a characteristic imprint of trilinear preheating in $\alpha$-attractors.

    ↳ astro-ph.COgr-qchep-phhep-thJCAP(2026)·0 citations
26. 26*

    Every Wrinkle Carries A Memory: An Integro-differential Bootstrap for Features in Cosmological Correlators

    Sadra Jazayeri🇬🇧 · Xi Tong🇬🇧 · Yuhang Zhu🇰🇷

    Motivated by cosmological observations, we push the cosmological bootstrap program beyond the de Sitter invariance lamppost by considering correlators that explicitly break scale invariance, thereby exhibiting primordial features. For exchange processes involving heavy fields with time-dependent masses and sound speeds, we demonstrate that locality in the bulk implies a set of integro-differential equations for correlators on the boundary. These scale-breaking boundary equations come with a built-in memory kernel in momentum-kinematic space encapsulating the universe's evolution during inflation. Specialising to heavy fields with sinusoidal masses such as those found in axion monodromy scenarios, we show that a powerful synthesis of microcausality and analyticity allows an analytical solution of these equations at leading order in the amplitude of mass oscillations. Meanwhile, we also unveil non-perturbative information in the integro-differential equations by resumming apparent infrared divergences as parametric resonances. In addition, we provide a first-of-its-kind example of numerical bootstrap that directly maps out the solution space of such boundary equations. Finally, we compute the bispectrum and uncover, in the squeezed limit, a scale-breaking cosmological collider signal, whose amplitude can be exponentially enhanced (with respect to the Boltzmann suppression) due to particle production triggered by high-frequency mass oscillations.

    ↳ hep-thastro-ph.COgr-qchep-phJHEP(2026)·12 citations
27. 27*

    Hadronic scattering in (1+1)D SU(2) lattice gauge theory from tensor networks

    João Barata🇨🇭 · Juan Hormaza🇨🇴 · Zhong-Bo Kang🇺🇸 · Wenyang Qian🇪🇸

    We present a first real-time study of hadronic scattering in a (1+1)-dimensional SU(2) lattice gauge theory with fundamental fermions using tensor-network techniques. Working in the gaugeless Hamiltonian formulation -- where the gauge field is exactly integrated out and no truncation of the electric flux is required -- we investigate scattering processes across sectors of fixed global baryon number $B=0,1,2$. These correspond respectively to meson-meson, meson-baryon, and baryon-baryon collisions. At strong coupling, the $B=0$ and $B=2$ channels exhibit predominantly elastic dynamics closely resembling those of the U(1) Schwinger model. In contrast, the mixed $B=1$ sector shows qualitatively new behavior: meson and baryon wave packets become entangled during the collision, and depending on their initial kinematics, the slower state becomes spatially delocalized while the faster one propagates ballistically. We characterize these processes through local observables, entanglement entropy, and the information-lattice, which together reveal how correlations build up and relax during the interaction. Our results establish a first benchmark for non-Abelian real-time scattering from first principles and open the path toward quantum-simulation studies of baryon-number dynamics and inelastic processes in gauge theories.

    ↳ hep-lathep-phnucl-thquant-phJHEP(2026)·16 citations
28. 28*

    Benchmarking Proton Tunneling Splittings with a Wavefunction-Based Double-Well Model: Application to the Formic Acid Dimer

    Krishna Kingkar Pathak🇮🇳

    Proton tunneling across hydrogen bonds is a fundamental quantum effect with implications for spectroscopy, catalysis, and biomolecular stability. While state-of-the-art instanton and path-integral methods provide accurate multidimensional tunneling splittings, simplified one-dimensional models remain valuable as conceptual and benchmarking tools. Here we develop a wavefunction-based framework for tunneling splittings using a Cornell-type double-well potential and apply it as a benchmark for hydrogen-bond tunneling. Analytical WKB estimates and numerical finite-difference solutions are compared across a range of barrier parameters, showing consistent agreement. As a test case, we map the formic acid dimer (FAD) barrier onto a quartic double-well model parameterized to reproduce the reported barrier height of $$\begin{gathered} V_b \\ approx2848 \\ text{cm}^{-1} \end{gathered}$$. The resulting tunneling splitting of about $$\begin{gathered} 0.037 \\ text{cm}^{-1} \end{gathered}$$ matches the reduced-dimensional calculations of Qu and Bowman. The close agreement between numerical and semiclassical results highlights the pedagogical and diagnostic value of one-dimensional models, while comparison with molecular benchmarks clarifies their limitations relative to full multidimensional quantum treatments.

    ↳ physics.chem-phhep-phnlin.CDquant-ph0 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.