Wed·Jun 19, 2024Wednesday·June 19, 2024

1. 01*

   Study on relativistic transformations for thermodynamic quantities: Boltzmann-Gibbs and Tsallis blast-wave models

   A.S. Parvan🇷🇺

   This study derives the relativistic transformations of thermodynamic quantities from the Lorentz transformations applied to the four-momentum components of a thermodynamic system, which is stationary in the inertial reference frame $K_0$ and moves at constant velocity relative to the laboratory frame $K$. Thermodynamic variables are introduced into the formalism via the zeroth component of the four-momentum in $K_0$, representing the system's internal energy. By treating the three-momentum as an independent state variable, thermodynamic quantities are defined by differentiating the zeroth component of the four-momentum (the Hamiltonian) in the reference frame $K$ with respect to the independent state variables, yielding the fundamental thermodynamic potential. This approach results in the Non-Planck transformations, which differ from the Planck transformations by a factor of $\alpha$. In contrast, by adopting the three-velocity as an independent state variable, thermodynamic quantities are obtained by differentiating the negative Lagrangian, derived from the zeroth component of the four-momentum via Legendre transformations, with respect to the independent state variables, producing the conjugate fundamental thermodynamic potential. This yields the Planck transformations. Conversely, the Ott transformations are derived from the zeroth component of the four-momentum by treating velocity as an independent state variable. This approach conflicts with the principles of mechanics, resulting in an energy that does not qualify as a thermodynamic potential. To validate these findings, we analyze an ultrarelativistic ideal gas of quarks and gluons within the Stefan-Boltzmann limit. Furthermore, we develop consistent Boltzmann-Gibbs and Tsallis blast-wave models for finite-volume freeze-out firecylinders in heavy ion collisions, incorporating Planck and Ott transformations.

   hep-phnucl-thEPJA(2025)·0 citations
2. 02*

   Unregulated Divergences of Feynman Integrals

   Wen Chen🇨🇳

   Feynman integrals can be expanded asymptotically with respect to some small parameters at the integrand level, a technique known as the expansion by regions. A naive expansion by regions may break down due to divergences not regulated by the spacetime dimension, exemplified by the rapidity divergences. A criterion to identify unregulated divergences is provided in this article. The analysis is conducted using both parametric and Mellin-Barnes representations, leading to a consistent conclusion. Based on this analysis, it is proven that the presence of unregulated divergences implies the degeneracies of regions.

   hep-phhep-thPLB(2025)·5 citations
3. 03*

   Dijet spectrum in nonlocal and asymptotically nonlocal theories

   Mikkie R. Anderson🇺🇸 · Christopher D. Carone🇺🇸

   Asymptotically nonlocal field theories approximate ghost-free nonlocal theories at low energies, yet are theories of finite order in the number of derivatives. These theories have an emergent nonlocal scale that regulates loop diagrams and can provide a solution to the hierarchy problem. Asymptotic nonlocality has been studied previously in scalar theories, Abelian and non-Abelian gauge theories with complex scalars, and linearized gravity. Here we extend that work by considering an asymptotically nonlocal generalization of QCD, which can be used for realistic phenomenological investigations. In particular, we derive Feynman rules relevant for the study of the production of dijets at hadron colliders and compute the parton-level cross sections at leading order. We use these to determine a bound on the scale of new physics from Large Hadron Collider data, both for a typical choice of model parameters, and in the nonlocal limit.

   hep-phhep-thPRD(2024)·1 citation
4. 04*

   Double-pole approximation for leading-order semi-leptonic vector-boson scattering at the LHC

   Ansgar Denner🇩🇪 · Daniele Lombardi🇩🇪 · Christopher Schwan🇩🇪

   Measuring vector-boson scattering beyond the fully-leptonic final state is becoming possible at the LHC, which demands to have a solid control on the theory predictions for all final states of this class of processes. In this work we present a full off-shell leading-order calculation for the process $\mathrm{pp}\to \ell {\nu }_{\ell }+4\mathrm{j}$ in two fiducial regions which are particularly relevant for its experimental measurement. In addition to the fully electroweak order, i.e. $\mathcal{O}({\alpha }^6)$, we complement our results with $\mathcal{O}({\alpha }_{\mathrm{s}}{\alpha }^5)$ and $\mathcal{O}({\alpha }_{\mathrm{s}}^2{\alpha }^4)$ for inclusive predictions. At $\mathcal{O}({\alpha }^6)$ we present for the first time a systematic treatment of the process in double-pole approximation and we perform a detailed study of its range of validity by considering inclusive and differential predictions compared to the full off-shell calculation.

   hep-phJHEP(2024)·13 citations
5. 05*

   Accessing the stringy structure of proton in the framework of Color Glass Condensate

   Wenchang Xiang🇨🇳 · Yanbing Cai🇨🇳 · Mengliang Wang🇨🇳 · Daicui Zhou🇨🇳

   To investigate the possible geometric structure of the proton, an improved stringy proton model is constructed beyond the smallest distance approximation, where the constituent quarks are connected by gluon tubes which merge at the Fermat point of the quark triangle. The exclusive diffractive vector meson production process in electron-proton deep inelastic scattering is used to test the stringy structure of the proton. We calculate the coherent and incoherent differential cross sections of the exclusive diffractive $J/\Psi$ photoproduction in the framework of Color Glass Condensate. The results show that our calculations are in good agreement with HERA data. Especially, our results give a better description of the HERA data at small $t$ as compared to the ones from the hot spot model where the constituent quarks are uncorrelated distributed in the proton. Meanwhile, the radius of the proton resulting from the improved stringy proton model is coincident with the one from fitting to the data from GlueX Collaboration at Jefferson Lab, which indicates that the predictive power of the stringy proton model is significantly improved once it goes beyond the smallest distance approximation. Moreover, we assume that the transverse shape of gluon tube satisfies Gaussian distribution, and explore the distribution width of the individual gluon tubes. We find an interesting result that the up quark induced gluon tube seems to have larger distribution width than the down quark induced gluon tube, which is favored by the HERA data.

   hep-phCommun.Theor.Phys.(2025)·1 citation
6. 06*

   Spin-independent interactions of Dirac Fermionic Dark Matter in the composite Higgs models

   M. G. Belyakova🇷🇺 · R. Nevzorov🇷🇺

   According to recent measurements, dark matter magnetic dipole moment is strongly constrained. In the composite Higgs models the magnetic dipole moment of the Dirac dark matter fermion and its mass can be suppressed by the approximate U(1) symmetry. We consider E_6 inspired composite Higgs model (E_6CHM) with U(1) symmetry violating operators, which give rise to dark matter's mass and coupling constant to Higgs boson. The dependence of the spin-independent dark matter-nucleon scattering cross section on the E_6CHM parameters is explored. We argue that there are regions of the parameter space which are still safe from all current constraints and may lead to spectacular LHC signatures.

   hep-phastro-ph.COhep-exhep-th+1PRD(2024)·4 citations
7. 07*

   Primordial Black Holes and Gravitational Waves in the $U(1{)}_{B-L}$ Extended Inert Doublet Model: A First-Order Phase Transition Perspective

   Indra Kumar Banerjee🇮🇳 · Ujjal Kumar Dey🇮🇳 · Shaaban Khalil🇪🇬

   We conduct an analysis of a $U(1{)}_{B-L}$ extended inert doublet model and obtained the parameter space allowing strong first order phase transitions. We show that a large part of the parameter space can cause double first-order phase transitions. Whereas both of these phase transitions can generate a detectable stochastic gravitational wave background, one of them can create primordial black holes with appreciable abundance. The primordial black holes generated at the high scale transition can account for the dark matter maintaining the correct relic abundance. We also show specific benchmark cases and their consequences from the aspect of primordial black holes and gravitational waves.

   hep-phastro-ph.HEgr-qcJHEP(2024)·18 citations
8. 08*

   Cosmic Strings from Tribrid Inflation

   Stefan Antusch🇨🇭 · Katarina Trailović🇸🇮

   Tribrid inflation is a class of supersymmetric inflation models where the scalar component of a matter superfield, or a $D$-flat direction of matter fields, drives inflation. Similar to Hybrid inflation, the end of inflation is reached when a "waterfall field", which was stabilized during inflation at a field value where the scalar potential features a large vacuum energy, starts rapidly rolling towards its minimum where a symmetry group $G$ is spontaneously broken. In contrast to standard supersymmetric Hybrid inflation, where the inflaton is a gauge singlet, in Tribrid inflation it can be a gauge non-singlet, which, via its vacuum expectation value, already breaks the gauge symmetry. This raises the question whether topological defects can still form after inflation in this class of models, and if so, which types of defects are generated. We investigate this question systematically in realisations of Tribrid inflation where $G=U(1)$ and we analyse under which conditions cosmic strings form. We find that in the considered cases where domain walls form, these are only temporary and do not invalidate the model realisations. We also discuss how our results can be used to analyse models of Tribrid inflation associated with the final step of $SO(10)$ breaking, where cosmic strings can be metastable and provide a promising explanation of the recent PTA results hinting at a stochastic gravitational wave background at nanohertz frequencies.

   hep-phastro-ph.COhep-thJCAP(2024)·5 citations
9. 09*

   Populating secluded dark sector with ultra-relativistic bubbles

   Aleksandr Azatov🇮🇹 · Xander Nagels🇧🇪 · Miguel Vanvlasselaer🇧🇪 · Wen Yin🇯🇵

   We study Dark Matter production during first order phase transitions from bubble-plasma collisions. We focus on scenarios where the Dark Matter sector is secluded and its interaction with the visible sector (including the Standard Model) originates from dimension-five and dimension-six operators. We find that such DM is generally heavy and has a large initial velocity, leading to the possibility of DM being warm today. We differentiate between the cases of weakly and strongly coupled dark sectors, where, in the latter case, we focus on glueball DM, which turns out to have very distinct phenomenological properties. We also systematically compute the Freeze-In production of the dark sector and compare it with the bubble-plasma DM abundances.

   hep-phastro-ph.COJHEP(2024)·24 citations
10. 10*

    Percolating Cosmic String Networks from Kination

    Joseph P. Conlon🇬🇧 · Edmund J. Copeland🇬🇧 · Edward Hardy🇬🇧 · Noelia Sánchez González🇬🇧

    We describe a new mechanism, whose ingredients are realised in string compactifications, for the formation of cosmic (super)string networks. Oscillating string loops grow when their tension $\mu$ decreases with time. If $2H+\dot{\mu }/\mu <0$, where $H$ is the Hubble parameter, loops grow faster than the scale factor and an initial population of isolated small loops (for example, produced by nucleation) can grow, percolate and form a network. This condition is satisfied for fundamental strings in the background of a kinating volume modulus rolling towards the asymptotic large volume region of moduli space. Such long kination epochs are motivated in string cosmology by both the electroweak hierarchy problem and the need to solve the overshoot problem. The tension of such a network today is set by the final vacuum; for phenomenologically appealing Large Volume Scenario (LVS) vacua, this would lead to a fundamental string network with $G\mu \sim 10^{-10}$.

    hep-phastro-ph.COhep-thPRD(2024)·25 citations
11. 11*

    High energy scattering in the Unitary Toy Model

    Alex Kovner (UCONN)🇺🇸 · Eugene Levin (Tel Aviv U.)🇮🇱 · Michael Lublinsky (Ben Gurion U.)🇮🇱

    We continue exploring the Unitary Toy Model (UTM) as a playground for high energy collisions in QCD. Our new approach is based on the diagonalization of the evolution Hamiltonian. Part of the spectrum can be identified with intercepts of dressed Pomerons. Analogously to QCD, a multi-Pomeron expansion of the $S$-matrix is badly divergent asymptotic series. Yet we succeeded to establish resummation procedures resulting in a well behaved $S$-matrix. In addition the Hamiltonian possesses negative eigenvalues, which dominate the approach of the $S$-matrix to saturation. We are hopeful that important lessons about BFKL-based Pomeron calculus could be taken from the toy world to real QCD.

    hep-phJHEP(2024)·7 citations
12. 12*

    Dark Photon Dark Matter Radio Signal from the Milky Way Electron Density

    Ariel Arza🇨🇳

    We consider Thomson-like processes between dark matter dark photons and free electrons in the Milky Way. The result is a radio signal background that can be detectable with current or future radio telescope arrays. In particular, we computed sensitivity prospects for the Atacama Large Millimeter Array (ALMA) radio telescope and for the future Square Kilometer Array (SKA), concluding that unconstrained parameter space in a wide range of dark photon masses can be probed.

    hep-phastro-ph.COastro-ph.GAPRD(2025)·3 citations
13. 13*

    Cold Darkogenesis: Dark Matter and Baryon Asymmetry in Light of the PTA Signal

    Kohei Fujikura🇯🇵 · Sudhakantha Girmohanta🇨🇳 · Yuichiro Nakai🇨🇳 · Zhihao Zhang🇨🇳

    We build upon the intriguing possibility that the recently reported nano-Hz gravitational wave signal by Pulsar Timing Array (PTA) experiments is sourced by a strong first-order phase transition from a nearly conformal dark sector. The phase transition has to be strongly supercooled to explain the signal amplitude, while the critical temperature has to be in the $\mathcal{O}$(GeV) range, as dictated by the peak frequency of the gravitational wave spectrum. However, the resulting strong supercooling exponentially dilutes away any pre-existing baryon asymmetry and dark matter, calling for a new paradigm of their productions. We then develop a mechanism of cold darkogenesis that generates a dark asymmetry during the phase transition from the textured dark $SU(2{)}_{\mathrm{D}}$ Higgs field. This dark asymmetry is transferred to the visible sector via neutron portal interactions, resulting in the observed baryon asymmetry. Furthermore, the mechanism naturally leads to the correct abundance of asymmetric dark matter, with self-interaction of the scale that is of the right order to solve the diversity problem in galactic rotation curves. Collider searches for mono-jets and dark matter direct detection experiments can dictate the viability of the model.

    hep-phastro-ph.COhep-exhep-thPLB(2024)·9 citations
14. 14*

    LO, NLO, and NNLO Parton Distributions for LHC Event Generators

    Juan Cruz-Martinez🇨🇭 · Stefano Forte🇮🇹 · Niccolo Laurenti🇮🇹 · Tanjona R. Rabemananjara🇳🇱 · Juan Rojo🇳🇱

    We present NNPDF4.0MC, a variant of the NNPDF4.0 set of parton distributions (PDFs) at LO, NLO and NNLO, with and without inclusion of the photon PDF, suitable for use with Monte Carlo (MC) event generators, which require PDFs to satisfy additional constraints in comparison to standard PDF sets. These requirements include PDF positivity down to a low scale $Q\sim 1$ GeV, smooth extrapolation in the very small and large $x$ regions, and numerically stable results even in extreme regions of phase space for all PDFs. We compare the NNPDF4.0MC PDFs to their baseline NNPDF4.0 counterparts, and to the NNPDF2.3LO set entering the Monash tune of the Pythia8 event generator. We briefly assess the phenomenological impact of these PDFs on the cross-sections for hard and soft QCD processes at the LHC.

    hep-phhep-exJHEP(2024)·16 citations
15. 15*

    Warm and Fuzzy Dark Matter: Free Streaming of Wave Dark Matter

    Rayne Liu🇺🇸 · Wayne Hu🇺🇸 · Huangyu Xiao🇺🇸

    Wave or fuzzy dark matter that is produced with relativistic wavenumbers exhibits free streaming effects analogous to warm or hot particle dark matter with relativistic momenta. Axions produced after inflation provide such a warm or mildly relativistic candidate, where the enhanced suppression and observational bounds are only moderately stronger than that from wave propagation of initially cold axions. More generally, the free streaming damping also impacts isocurvature fluctuations from generation in causally disconnected patches. As coherent spatial fluctuations free stream away they leave incoherent and transient superpositions in their wakes. These multiple wave momentum streams are the wave analogue of particle phase space fluctuations or directional collisionless damping of massive neutrinos or hot dark matter. The observable impact on both adiabatic and isocurvature fluctuations of fuzzy dark matter can differ from their cold dark matter counterparts due to free streaming depending on how warm or hot is their momentum distribution.

    hep-phastro-ph.COPRD(2025)·28 citations
16. 16*

    The distribution amplitude of the ${\eta }_c$-meson

    Benoît Blossier🇫🇷 · Mariane Mangin-Brinet🇫🇷 · José Manuel Morgado Chávez🇫🇷 · Teseo San José

    In this proceeding we determine the distribution amplitude of the ${\eta }_c$-meson from first principles. This quantity appears as a consequence of factorization theorems, and it is necessary to compute the amplitude of multiple exclusive processes. Since it is defined along a light-cone, its calculation via lattice QCD was impossible until recently, when a generalization to Euclidean metric was proposed, and a connection to the physical limit was established. We briefly explain the method of short distance factorization, which allows us to compute the distribution amplitude, and our lattice setup. After summarizing the steps for the continuum and chiral extrapolation, we present our results and compare them to two alternative determinations, one using non-relativistic QCD and another solving the Dyson-Schwinger equations; we find a large discrepancy with the former.

    ↳ hep-lathep-phPoS(2025)·1 citation
17. 17*

    Constraining neutron star matter from the slope of the mass-radius curves

    Márcio Ferreira🇵🇹 · Constança Providência🇵🇹

    We analyse the implications of information about local derivatives from the mass-radius diagram in neutron star matter. It is expected that the next generation of gravitational wave and electromagnetic detectors will allow the determination of the neutron star radius and mass with a small uncertainty. Observations of neutron stars clustered around a given neutron star mass allow the estimation of local derivatives in the $M(R)$ diagram, which can be used to constrain neutron star properties. From a model-independent description of the neutron star equation of state, it is shown that a $M(R)$ curve with a negative slope at 1.4$M_{\odot }$ predicts a $2M_{\odot }$ neutron star radius below 12 km. Furthermore, a maximum mass below 2.3$M_{\odot }$ is obtained if the $M(R)$ slope is negative in the whole range of masses above $1M_{\odot }$, and a maximum mass above 2.4$M_{\odot }$ requires the $M(R)$ slope to be positive in some range of masses. Constraints on the mass-radius curve of neutron stars will place strong constraints on microscopic models.

    ↳ nucl-thastro-ph.HEhep-phPRD(2024)·22 citations
18. 18*

    Quantum Kerr Black Hole from Matrix Theory of Quantum Gravity

    Chong-Sun Chu🇹🇼

    Recently, a quantum mechanical theory of quantum spaces described by a large $N$ non-commutative coordinates is proposed as a model for quantum gravity [1]. In this paper, we construct Kerr black hole as a rotating noncommutative geometry solution of this theory. Due to rotation, the fuzzy sphere is deformed into a fuzzy ellipsoid, which matches exactly the outer horizon of the Kerr black hole in the Boyer-Lindquist coordinates. Together with a half-filled Fermi sea, the fuzzy solution reproduces the Bekenstein-Hawking entropy as well as the mass and angular momentum of the Kerr black hole. These results provide support that the proposed quantum mechanics of quantum spaces as a model of quantum gravity.

    ↳ hep-thgr-qchep-phPRD(2025)·9 citations
19. 19*

    Structure of Massive Gauge/Gravity Scattering Amplitudes, Equivalence Theorems, and Extended Double-Copy with Compactified Warped Space

    Yanfeng Hang🇺🇸 · Wei-Wei Zhao🇨🇳 · Hong-Jian He🇨🇳 · Yin-Long Qiu🇨🇳

    We study the structure of scattering amplitudes of massive Kaluza-Klein (KK) states in the compactified 5-dimensional warped gauge and gravity theories. We present systematic formulations of the gauge theory equivalence theorem (GAET) and the gravitational equivalence theorem (GRET) for warped KK theories in $R_{\xi }^{}$ gauge, where the GAET connects the scattering amplitudes of longitudinal KK gauge bosons to that of the corresponding KK Goldstone bosons and the GRET connects the scattering amplitudes of KK gravitons of helicity-zero (helicity-one) to that of the corresponding gravitational scalar (vector) KK Goldstone bosons. We analyze the structure of 3-point and 4-point scattering amplitudes of massive KK gauge bosons and of massive KK gravitons as well as their corresponding Goldstone bosons. We first prove the GAET and GRET explicitly for the fundamental 3-point KK gauge/gravity scattering amplitudes. We then demonstrate that the validity of the GAET and GRET for 4-point gauge/gravity scattering amplitudes can be reduced to the validity of GAET and GRET for 3-point gauge/gravity scattering amplitudes at tree level. With these, we study the double-copy construction of KK scattering amplitudes in the warped gauge/gravity theories. We newly realize the double-copy for massive 3-point full gauge/gravity amplitudes at tree level under proper correspondences of color-kinematics and of gauge/gravity couplings, whereas we can construct the double-copy for 4-point KK gauge/gravity amplitudes to the leading order (LO) of high energy expansion. We also conjecture that this LO double-copy construction can be extended to $N$-point scattering amplitudes with $N⩾5$.

    ↳ hep-thgr-qchep-phJHEP(2025)·4 citations
20. 20*

    Neural Ordinary Differential Equations for Mapping the Magnetic QCD Phase Diagram via Holography

    Rong-Gen Cai🇨🇳 · Song He🇨🇳 · Li Li🇨🇳 · Hong-An Zeng🇨🇳

    The QCD phase diagram is crucial for understanding strongly interacting matter under extreme conditions, with major implications for cosmology, neutron stars, and heavy-ion collisions. We present a novel holographic QCD model utilizing neural ordinary differential equations (ODEs) to map the QCD phase diagram under magnetic field $B$, baryon chemical potential ${\mu }_B$, and temperature $T$. By solving the inverse problem of constructing a gravitational theory from Lattice QCD data, we reveal an unprecedentedly rich phase structure at finite $B$, including multiple critical endpoints (CEPs) in strong magnetic fields. Specifically, for {$B=1.618{\mathrm{GeV}}^2=2.592\times 10^{19}$ Gauss}, we identify two distinct CEPs at $(T_C=87.3\mathrm{MeV},{\mu }_C=115.9\mathrm{MeV})$ and $(T_C=78.9\mathrm{MeV},{\mu }_C=244.0\mathrm{MeV})$. Notably, the critical exponents vary depending on the CEP's location, and the conventional scaling relations can be violated in the presence of strong magnetic fields. These findings significantly advance our understanding of the QCD phase structure and provide concrete predictions for experimental validation at upcoming facilities such as FAIR, JPARC-HI, and NICA.

    ↳ hep-thgr-qchep-phnucl-thSCPMA(2026)·43 citations
21. 21*

    Every Poincaré gauge theory is conformal: a compelling case for dynamical vector torsion

    Will Barker🇬🇧 · Michael Hobson🇬🇧 · Anthony Lasenby🇬🇧 · Yun-Cherng Lin🇬🇧 · Zhiyuan Wei🇬🇧

    The Poincaré gauge theory (PGT) of gravity provides a viable formulation of general relativity (Einstein-Cartan theory), and a popular model-building framework for modified gravity with torsion. Notoriously, however, the PGT terms which propagate vector torsion lead to strongly-coupled ghosts: the modern view is that only scalar torsion can propagate. To fix this, we revisit the concept of embedding explicit mass scales in scale-invariant theories, showing how the Klein-Gordon theory naturally leads to a slowly-rolling inflaton. We then show that the unique scale-invariant embedding of PGT leads to two new terms, one of which is the Maxwell term for vector torsion. We provide the full spectrum of quantum particles in the resulting theory. Our result means that every PGT is conformal and - after a two-decade hiatus - vector torsion is back on the menu.

    ↳ hep-thgr-qchep-phPLB(2025)·16 citations
22. 22*

    Large Blue Spectral Index From a Conformal Limit of a Rotating Complex Scalar

    Daniel J. H. Chung🇺🇸 · Sai Chaitanya Tadepalli🇺🇸

    One well known method of generating a large blue spectral index for axionic isocurvature perturbations is through a flat direction not having a quartic potential term for the radial partner of the axion field. In this work, we show how one can obtain a large blue spectral index even with a quartic potential term associated with the Peccei-Quinn symmetry breaking radial partner. We use the fact that a large radial direction with a quartic term can naturally induce a conformal limit which generates an isocurvature spectral index of 3. We point out that this conformal representation is intrinsically different from both the ordinary equilibrium axion scenario or massless fields in Minkowski spacetime. Another way to view this limit is as a scenario where the angular momentum of the initial conditions slows down the radial field or as a superfluid limit. Quantization of the non-static system in which derivative of the radial field and the derivative of the angular field do not commute is treated with great care to compute the vacuum state. The parametric region consistent with axion dark matter and isocurvature cosmology is discussed.

    ↳ astro-ph.COhep-phPRD(2025)·12 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.