Thu·Sep 7, 2023Thursday·September 7, 2023

1. 01*

   Testing Meson Portal Dark Sector Solutions to the MiniBooNE Anomaly at CCM

   A.A. Aguilar-Arevalo🇲🇽 · S. Biedron🇺🇸 · J. Boissevain🇺🇸 · M. Borrego🇺🇸 · L. Bugel🇺🇸 · M. Chavez-Estrada🇲🇽 · J.M. Conrad🇺🇸 · R.L. Cooper🇺🇸 · A. Diaz🇺🇸 · J.R. Distel🇺🇸 · J.C. D'Olivo🇲🇽 · E. Dunton🇺🇸 and 33 other authors

   A solution to the MiniBooNE excess invoking rare three-body decays of the charged pions and kaons to new states in the MeV mass scale was recently proposed as a dark-sector explanation. This class of solution illuminates the fact that, while the charged pions were focused in the target-mode run, their decay products were isotropically suppressed in the beam-dump-mode run in which no excess was observed. This suggests a new physics solution correlated to the mesonic sector. We investigate an extended set of phenomenological models that can explain the MiniBooNE excess as a dark sector solution, utilizing long-lived particles that might be produced in the three-body decays of the charged mesons and the two-body anomalous decays of the neutral mesons. Over a broad set of interactions with the long-lived particles, we show that these scenarios can be compatible with constraints from LSND, KARMEN, and MicroBooNE, and evaluate the sensitivity of the ongoing and future data taken by the Coherent CAPTAIN Mills experiment (CCM) to a potential discovery in this parameter space. See addendum for updated predictions for future MicroBooNE sensitivity.

   hep-phhep-exPRD(2024)·16 citations
2. 02*

   Vortex Creep Heating vs. Dark Matter Heating in Neutron Stars

   Motoko Fujiwara🇩🇪 · Koichi Hamaguchi🇯🇵 · Natsumi Nagata🇯🇵 · Maura E. Ramirez-Quezada🇯🇵

   Dark matter particles captured in neutron stars deposit their energy as heat. This DM heating effect can be observed only if it dominates over other internal heating effects in NSs. In this work, as an example of such an internal heating source, we consider the frictional heating caused by the creep motion of neutron superfluid vortex lines in the NS crust. The luminosity of this heating effect is controlled by the strength of the interaction between the vortex lines and nuclei in the crust, which can be estimated from the many-body calculation of a high-density nuclear system as well as through the temperature observation of old NSs. We show that both the temperature observation and theoretical calculation suggest that the vortex creep heating dominates over the DM heating. The vortex-nuclei interaction must be smaller than the estimated values by several orders of magnitude to overturn this.

   hep-phastro-ph.HEPLB(2024)·20 citations
3. 03*

   General Heavy WIMP Nucleon Elastic Scattering

   Qing Chen🇨🇳 · Gui-Jun Ding🇨🇳 · Richard J. Hill🇺🇸

   Heavy WIMP (weakly-interacting-massive-particle) effective field theory is used to compute the WIMP-nucleon scattering rate for general heavy electroweak multiplets through order $m_W/M$, where $m_W$ and $M$ denote the electroweak and WIMP mass scales. The lightest neutral component of such an electroweak multiplet is a candidate dark matter particle, either elementary or composite. Existing computations for certain representations of electroweak ${\mathrm{SU}(2)}_W\times {\mathrm{U}(1)}_Y$ reveal a cancellation of amplitudes from different effective operators at leading and subleading orders in $1/M$, yielding small cross sections that are below current dark matter direct detection experimental sensitivities. We extend those computations and consider all low-spin (spin-0, spin-1/2, spin-1, spin-3/2) heavy electroweak multiplets with arbitrary ${\mathrm{SU}(2)}_W\times {\mathrm{U}(1)}_Y$ representations and provide benchmark cross section results for dark matter direct detection experiments. For most self-conjugate TeV WIMPs with isospin $\le 3$, the cross sections are below current experimental limits but within reach of next-generation experiments. An exception is the case of pure electroweak doublet, where WIMPs are hidden below the neutrino floor.

   hep-phastro-ph.COhep-exPRD(2023)·9 citations
4. 04*

   QED effects in inclusive semi-leptonic $B$ decays

   Dante Bigi🇨🇭 · Marzia Bordone🇨🇭 · Paolo Gambino🇮🇹 · Ulrich Haisch🇩🇪 · Andrea Piccione🇮🇹

   We analyse in detail the QED corrections to the total decay width and the moments of the electron energy spectrum of the inclusive semi-leptonic $B\to X_{c}e\nu$ decay. Our calculation includes short-distance electroweak corrections, the complete $\mathcal{O}(\alpha )$ partonic terms and leading-logarithmic QED effects up to $\mathcal{O}({\Lambda }_{\mathrm{QCD}}^3/m_b^3)$. A comprehensive numerical comparison of our results against those obtained with the Monte Carlo (MC) tool PHOTOS is presented. While the comparison indicates good overall agreement, our computation contains QED effects not included in PHOTOS and should therefore better describe photon radiation to $B\to X_{c}e\nu$ as measured by the $B$-factories. Our calculations represent the first steps in the construction of a fully differential higher-order QED MC generator for inclusive semi-leptonic $B$ decays.

   hep-phhep-exJHEP(2023)·24 citations
5. 05*

   Atomic electron shell excitations in double-$\beta$ decay

   M.I. Krivoruchenko🇷🇺 · K.S. Tyrin🇷🇺 · F.F. Karpeshin🇷🇺

   The problem of the transition of electron shells of atoms to excited states in the process of neutrinoless double-$\beta$ decay is investigated. This subject is crucial for modeling the energy spectrum of $\beta$-electrons, which is sensitive to the mass and Majorana nature of neutrinos. The dependence of the obtained results on the atomic number indicates the determining role of the Feinberg--Migdal effect in the electron shell excitations. We report the overlap amplitudes of the electron shells of the parent atom and the daughter ion for eleven atoms, the two-neutrino double-$\beta$ decay of which was observed experimentally. In around one-fourth of the cases where the structure of the electron shells is inherited from the parent atom, there is a transition to the ground state or the excited state with the lowest energy. The de-excitation of the daughter ion in the latter scenario is accompanied by the emission of photons in the ultraviolet range, which can serve as an auxiliary signature of double-$\beta$ decay. The average excitation energy of the electron shells ranges between 300 and 800 eV, with the variance ranging from $(1.7\mathrm{keV}{)}^2$ in calcium to $(14\mathrm{keV}{)}^2$ in uranium.

   hep-phphysics.atom-phJETP Lett.(2023)·1 citation
6. 06*

   Total Born cross section of $e^{+}{e}^{-}$-pair production by an electron in the Coulomb field of a nucleus

   Roman N. Lee🇷🇺 · Alexey A. Lyubyakin🇷🇺 · Vladimir A. Smirnov🇷🇺

   We calculate the total Born cross section of the $e^{+}{e}^{-}$-pair production by an electron in the field of a nucleus (trident process) using the modern multiloop methods. For general energies we obtain the cross section in terms of converging power series. The threshold asymptotics and the high-energy asymptotics are obtained analytically. In particular, we obtain additional contribution to the Racah formula due to the identity of the final electrons. Besides, our result for the leading term of the high-energy asymptotics reveals a typo in an old Racah paper [Racah1937].

   hep-phPLB(2024)·5 citations
7. 07*

   Holographic stability for non-$q\bar{q}$ candidates

   Miguel Angel Martin Contreras🇨🇳 · Alfredo Vega🇨🇱

   In the context of bottom-up AdS/QCD models, we discuss how the configurational entropy can describe heavy non-$q\bar{q}$ states. Using the non-quadratic softwall model, introduced to describe non-linear Regge trajectories, we parametrize different multiquark and exotic meson structures to describe $Z_c$, $\psi$, and $Z_b$ states as non-$q\bar{q}$ hadrons in terms of stability. We found that $Z_c$ is better described as a hybrid meson with one gluon tube, $\psi$ as hadrocharmonium, and $Z_b$ as hadronic molecule.

   hep-phhep-thPRD(2023)·25 citations
8. 08*

   Solutions to the Balitsky-Kovchegov equation including the dipole orientation

   J. Cepila🇨🇿 · J. G. Contreras🇨🇿 · M. Vaculciak🇨🇿

   Solutions of the target-rapidity Balitsky-Kovchegov (BK) equation are studied considering, for the first time, the complete impact-parameter dependence, including the orientation of the dipole with respect to the impact-parameter vector. In our previous work, it has been demonstrated that the spurious Coulomb tails could be tamed using the collinearly-improved kernel and an appropriate initial condition in the projectile-rapidity BK equation. Introducing a different interpretation of the evolution variable, the target-rapidity formulation of the BK equation brings non-locality in rapidity and a kernel modification, removing the term that previously helped to suppress the Coulomb tails. To address this newly emerged non-locality, three different prescriptions are explored here to take into account the rapidities preceding the initial condition. Two of these approaches induce mild Coulomb tails, while the other is free from this effect within the studied rapidity range. The range is chosen to correspond to that of interest for existing and future experiments. To demonstrate that this set up can be used for phenomenological studies, the obtained solutions are used to compute the F2 structure function of the proton and the diffractive photo- and electro-production of J/{\psi} off protons. The predictions agree well with HERA data, confirming that the target-rapidity Balitsky-Kovchegov equation with the full impact-parameter dependence is a viable tool to study the small Bjorken-x limit of perturbative QCD at current facilities like RHIC and LHC as well as in future colliders like the EIC.

   hep-phPLB(2024)·9 citations
9. 09*

   When Energy Goes Missing: New Physics in $b\to s\nu \nu$ with Sterile Neutrinos

   Tobias Felkl🇦🇺 · Anjan Giri🇮🇳 · Rukmani Mohanta🇮🇳 · Michael A. Schmidt🇦🇺

   Belle II recently reported the first measurement of $B^{+}\to K^{+}+\mathrm{inv}$, which is $2.8\sigma$ above the Standard Model prediction. We explore the available parameter space of new physics within Standard Model effective field theory extended by sterile neutrinos ($\nu$SMEFT) and provide predictions for the other $B\to K^{(\star )}+\mathrm{inv}$ decay modes and invisible $B_s$ decays. We also briefly comment on charged current decays $B\to D^{(\star )}\ell \bar{\nu }$ and possible ultraviolet completions of the relevant $\nu$SMEFT operators.

   hep-phEPJC(2023)·62 citations
10. 10*

    Role of unphysical neutrino phases in the phenomenology of consistently defined textures. Case study: traceless neutrino mass matrix

    N. Chamoun (Dam. Univ. )🇸🇾 · E. I. Lashin (Ain Shams & Zewail city)🇪🇬

    We highlight the role played by the unphysical phases in the definition of neutrino mass matrix, showing it does not relate to mere semantics, rather it has an effect on the phenomenology. As a case study, we take the neutrino mass matrix texture characterized by a vanishing trace, and study the effect of the phases, physical and unphysical, in its definition. We undergo a thorough phenomenological analysis, first (second) when the unphysical (CP) phases are vanishing, then move on to the general case where all phases exist. We stress that the effect of the unphysical phases on the phenomenology originates from changing the texture definition upon introducing them, while they are not observable. Finally we present a theoretical realization of the texture based on $A_5$ non-abelian flavor symmetry, which is also related to a consistently defined texture.

    hep-ph3 citations
11. 11*

    Influence of dynamical screening of four-quarks interaction on the chiral phase diagram

    Michał Szymański🇵🇱 · Pok Man Lo🇵🇱 · Krzysztof Redlich🇵🇱 · Chihiro Sasaki🇵🇱

    We investigate the effect of screening of the four-quarks contact interactions by the ring diagram at finite temperature and density in an effective chiral model inspired by QCD in the Coulomb gauge. As a consequence, a medium-dependent coupling naturally emerges which, in a class of chiral models, brings the chiral crossover temperature down to the value calculated in LQCD at low net-baryon density. Furthermore, it implies a stronger divergence of the chiral susceptibility at the critical point compared to the mean-field dynamics. At vanishing temperature, however, the transition sets in at unphysically small chemical potential, indicating a need for additional effects to compensate for the screening strength. We discuss the properties of an effective potential for a class of models described by momentum-independent gap equations. In particular, we introduce the method to construct an approximate effective potential from the gap equations to determine the location of the first-order phase transition.

    hep-phnucl-thPRD(2024)·3 citations
12. 12*

    Classifying the CP properties of the ggH coupling in H+2j production

    Henning Bahl🇺🇸 · Elina Fuchs🇨🇭 · Marc Hannig🇩🇪 · Marco Menen🇩🇪

    The Higgs-gluon interaction is crucial for LHC phenomenology. To improve the constraints on the CP structure of this coupling, we investigate Higgs production with two jets using machine learning. In particular, we exploit the CP sensitivity of the so far neglected phase space region that differs from the typical vector boson fusion-like kinematics. Our results indicate that further improvements in the current experimental limits could be achievable using our techniques. We also discuss the most relevant observables and how CP violation in the Higgs-gluon interaction can be disentangled from CP violation in the interaction between the Higgs boson and massive vector bosons. Assuming the absence of CP-violating Higgs interactions with coloured beyond-the-Standard-Model states, our projected limits on a CP-violating top-Yukawa coupling are competitive with more direct probes like top-associated Higgs production and limits from a global fit.

    hep-phhep-exSciPost Phys.Core(2025)·13 citations
13. 13*

    CP-Violation with Neutrino Disappearance Alone

    Peter B. Denton🇺🇸

    The best way to probe CP violation in the lepton sector is with long-baseline accelerator neutrino experiments in the appearance mode: the appearance of ${\nu }_e$ in predominantly ${\nu }_{\mu }$ beams. Here we show that it is possible to discover CP violation with disappearance experiments only, by combining JUNO for electron neutrinos and DUNE or Hyper-Kamiokande for muon neutrinos. While the maximum sensitivity to discover CP is quite modest ($1.6\sigma$ with 6 years of JUNO and 13 years of DUNE), some values of $\delta$ may be disfavored by $>3\sigma$ depending on the true value of $\delta$.

    hep-phhep-exPRL(2024)·12 citations
14. 14*

    Gamma-Ray Lines in 15 Years of Fermi-LAT Data: New Constraints on Higgs Portal Dark Matter

    Pedro De La Torre Luque🇸🇪 · Juri Smirnov🇬🇧 · Tim Linden🇸🇪

    Monoenergetic $\gamma$-ray spectral lines are among the cleanest signatures of dark matter annihilation. We analyze 15 years of Fermi-LAT data, find no spectral lines, and place strong constraints on dark matter annihilation to monoenergetic $\gamma$-rays. Additionally, we produce the first double-line analysis of the coupled signals from $\gamma \gamma$ and $Z\gamma$ lines, which proves particularly powerful for dark matter masses above $\sim 150$~GeV. From our constraints on a double-line feature, we investigate and constrain some minimal models where the Galactic Center Excess (GCE) can be fit by dark matter annihilation through the Higgs boson into Standard Model particles.

    hep-phastro-ph.HEPRD(2024)·20 citations
15. 15*

    Gluon Generalized TMDs and Wigner Distributions in boost invariant longitudinal space

    Sujit Jana🇮🇳 · Vikash Kumar Ojha🇮🇳 · Tanmay Maji🇮🇳

    We present the gluon generalized TMDs for non-zero skewness and Wigner distributions in the boost invariant longitudinal space. The boost-invariant longitudinal space is defined as $\sigma =\frac{1}{2}{b}^{-}{\Delta }^{+}$ and is conjugate to the skewness variable $\xi$. We use the dressed quark model, where a high-energetic quark is dressed by a gluon. This two-particle system has the advantage of addressing both the gluon and the quark sectors. The different contributions in Wigner distributions coming from different polarization of gluon and the dressed quark system are investigated. The Wigner distributions are obtained by taking the Fourier transformation of generalized TMDs, which we derive for the first time for non-zero skewness in dressed quark model.

    hep-phNPA(2025)·14 citations
16. 16*

    Searches for baryon number violation in the HIBEAM-NNBAR experiment at the European Spallation Source

    Bernhard Meirose🇸🇪

    The HIBEAM-NNBAR program is a proposed two-stage experiment at the European Spallation Source (ESS) designed to search for baryon number violation, which is - together with C and CP violation - one of the three fundamental Sakharov conditions to explain the observed baryon asymmetry of the Universe. Taking advantage of the ESS' unique capabilities as the future brightest neutron source, the experiment will make high sensitivity searches for neutrons converting into antineutrons and/or sterile neutrons.

    ↳ physics.ins-dethep-exhep-phnucl-exPoS·0 citations
17. 17*

    Collisional flavor swap with neutrino self-interactions

    Chinami Kato🇯🇵 · Hiroki Nagakura🇯🇵 · Lucas Johns🇺🇸

    Neutrinos play pivotal roles in determining fluid dynamics, nucleosynthesis, and their observables in core-collapse supernova (CCSN) and binary neutron star merger (BNSM). In this paper, we present a novel phenomenon, collisional flavor swap, in which neutrino-matter interactions trigger the complete interchange of neutrino spectra between two different flavors, aided by neutrino self-interactions. We find that a necessary condition to trigger the collisional swap is occurrences of resonance-like collisional flavor instability. In cases where neutrino self-interactions substantially dominate over the collision rate, the collisional swap occurs in the entire neutrino energy spectrum, while intriguing energy dependent features can emerge after the completion of flavor swap. Since flavor swaps correspond to the most extreme case in flavor conversions, they have a great potential to affect CCSN and BNSM phenomena.

    ↳ astro-ph.HEhep-phPRD(2024)·30 citations
18. 18*

    Moment of Inertia for Axisymmetric Neutron Stars in the Standard-Model Extension

    Yiming Dong🇨🇳 · Zexin Hu🇨🇳 · Rui Xu🇨🇳 · Lijing Shao🇨🇳

    We develop a consistent approach to calculate the moment of inertia (MOI) for axisymmetric neutron stars (NSs) in the Lorentz-violating Standard-Model Extension (SME) framework. To our knowledge, this is the first relativistic MOI calculation for axisymmetric NSs in a Lorentz-violating gravity theory other than deformed, rotating NSs in the General Relativity. Under Lorentz violation, there is a specific direction in the spacetime and NSs get stretched or compressed along that direction. When a NS is spinning stationarily along this direction, a conserved angular momentum and the concept of MOI are well defined. In the SME framework, we calculate the partial differential equation governing the rotation and solve it numerically with the finite element method to get the MOI for axisymmetric NSs caused by Lorentz violation. Besides, we study an approximate case where the correction to the MOI is regarded solely from the deformation of the NS and compare it with its counterpart in the Newtonian gravity. Our formalism and the numerical method can be extended to other theories of gravity for static axisymmetric NSs.

    ↳ gr-qcastro-ph.HEhep-phPRD(2023)·7 citations
19. 19*

    Production of doubly charmed hadron ${\Xi }_{cc}^{++}$ and $T_{cc}^{+}$ in relativistic heavy ion collisions

    Baoyi Chen🇨🇳 · Meimei Yang🇨🇳 · Ge Chen🇬🇧 · Jiaxing Zhao🇫🇷 · Xiao-hai Liu🇨🇳

    Heavy ion collisions provide a unique opportunity for studying the properties of exotic hadrons with two charm quarks. The production of $T_{cc}^{+}$ is significantly enhanced in nuclear collisions compared to proton-proton collisions due to the creation of multiple charm pairs. In this study, we employ the Langevin equation in combination with the Instantaneous Coalescence Model (LICM) to investigate the production of $T_{cc}^{+}$ and ${\Xi }_{cc}^{++}$ which consists of two charm quarks. We consider $T_{cc}^{+}$ as molecular states composed of $D$ and $D^{\ast }$ mesons. The Langevin equation is used to calculate the energy loss of charm quarks and $D$ mesons in the hot medium. The hadronization process, where charm quarks transform into each $D$ state as constituents of $T_{cc}^{+}$ production, is described using the coalescence model. The coalescence probability between $D$ and $D^{\ast }$ is determined by the Wigner function, which encodes the information of the $T_{cc}^{+}$ wave function. Our results show that the $T_{cc}^{+}$ production varies by approximately one order of magnitude when different widths in the Wigner function, representing distinct binding energies of $T_{cc}^{+}$, are considered. This variation offers valuable insights into the nature of $T_{cc}^{+}$ through the analysis of its wave function. The ${\Xi }_{cc}^{++}$ is treated as a hadronic state produced at the hadronization of the deconfined matter. Its production is also calculated as a comparison with the molecular state $T_{cc}^{+}$.

    ↳ nucl-thhep-phPRC(2024)·6 citations
20. 20*

    Macroscopic Quantum Response to Gravitational Waves

    Asuka Ito🇯🇵 · Ryuichiro Kitano🇯🇵

    We study the excitation of a one-electron quantum cyclotron by gravitational waves. The electron in such as a penning trap is prepared to be at the lowest Landau level, which has an infinite degeneracy parameterized by the size of the wave function. We find that the excitation rate from the ground state to the first excited state is enhanced by the size of the electron wave function: an electron with a larger wave function feels gravitational waves more. As a consequence, we derive a good sensitivity to gravitational waves at a macroscopic one-electron quantum cyclotron.

    ↳ gr-qchep-exhep-phquant-phJCAP(2024)·13 citations
21. 21*

    Cosmological Parameter Forecasts for a CMB-HD Survey

    Amanda MacInnis🇺🇸 · Neelima Sehgal🇺🇸 · Miriam Rothermel🇺🇸

    We present forecasts on cosmological parameters for a CMB-HD survey. For a $\Lambda$CDM + $N_{eff}$ + $\sum m_{\nu }$ model, we find $\sigma (n_s)=0.0013$ and $\sigma (N_{eff})=0.014$ using CMB and CMB lensing multipoles in the range of $\ell \in [30,20000]$, after adding anticipated residual foregrounds, delensing the acoustic peaks, and adding DESI BAO data. This is about a factor of two improvement in ability to probe inflation via $n_s$ compared to precursor CMB surveys. The $N_{eff}$ constraint can rule out light thermal particles back to the end of inflation with 95% CL; for example, it can rule out the QCD axion in a model-independent way assuming the Universe's reheating temperature was high enough that the axion thermalized. We find that delensing the acoustic peaks and adding DESI BAO tightens parameter constraints. We also find that baryonic effects can bias parameters if not marginalized over, and that uncertainties in baryonic effects can increase parameter error bars; however, the latter can be mitigated by including information about baryonic effects from kinetic and thermal Sunyaev-Zel'dovich measurements by CMB-HD. The CMB-HD likelihood and Fisher estimation codes used here are publicly available; the likelihood is integrated with Cobaya to facilitate parameter forecasting.

    ↳ astro-ph.COhep-phPRD(2024)·16 citations
22. 22*

    Magnetized Baryonic layer and a novel BPS bound in the gauged-Non-Linear-Sigma-Model-Maxwell theory in (3+1)-dimensions through Hamilton-Jacobi equation

    Fabrizio Canfora🇨🇱

    It is show that one can derive a novel BPS bound for the gauged Non-Linear-Sigma-Model (NLSM) Maxwell theory in (3+1) dimensions which can actually be saturated. Such novel bound is constructed using Hamilton-Jacobi equation from classical mechanics. The configurations saturating the bound represent Hadronic layers possessing both Baryonic charge and magnetic flux. However, unlike what happens in the more common situations, the topological charge which appears naturally in the BPS bound is a non-linear function of the Baryonic charge. This BPS bound can be saturated when the surface area of the layer is quantized. The far-reaching implications of these results are discussed. In particular, we determine the exact relation between the magnetic flux and the Baryonic charge as well as the critical value of the Baryonic chemical potential beyond which these configurations become thermodynamically unstable.

    ↳ hep-thastro-ph.HEcond-mat.supr-conhep-ph+1JHEP(2023)·18 citations
23. 23*

    Was There a 3.5 keV Line?

    Christopher Dessert🇺🇸 · Joshua W. Foster🇺🇸 · Yujin Park🇺🇸 · Benjamin R. Safdi🇺🇸

    The 3.5 keV line is a purported emission line observed in galaxies, galaxy clusters, and the Milky Way whose origin is inconsistent with known atomic transitions and has previously been suggested to arise from dark matter decay. We systematically re-examine the bulk of the evidence for the 3.5 keV line, attempting to reproduce six previous analyses that found evidence for the line. Surprisingly, we only reproduce one of the analyses; in the other five we find no significant evidence for a 3.5 keV line when following the described analysis procedures on the original data sets. For example, previous results claimed 4$\sigma$ evidence for a 3.5 keV line from the Perseus cluster; we dispute this claim, finding no evidence for a 3.5 keV line. We find evidence for background mismodeling in multiple analyses. We show that analyzing these data in narrower energy windows diminishes the effects of mismodeling but returns no evidence for a 3.5 keV line. We conclude that there is little robust evidence for the existence of the 3.5 keV line. Some of the discrepancy of our results from those of the original works may be due to the earlier reliance on local optimizers, which we demonstrate can lead to incorrect results. For ease of reproducibility, all code and data are publicly available.

    ↳ astro-ph.COastro-ph.HEhep-phApJ(2024)·38 citations
24. 24*

    ABJ anomaly as a U(1) symmetry and Noether's theorem

    Valentin Benedetti🇦🇷 · Horacio Casini🇦🇷 · Javier M. Magan🇦🇷

    The Adler-Bell-Jackiw anomaly determines the violation of chiral symmetry when massless fermions are coupled to an abelian gauge field. In its seminal paper, Adler noticed that a modified chiral U(1) symmetry could still be defined, at the expense of being generated by a non-gauge-invariant conserved current. We show this internal U(1) symmetry has the special feature that it transforms the Haag duality violating sectors (or non-local operator classes). This provides a simple unifying perspective on the origin of anomaly quantization, anomaly matching, applicability of Goldstone theorem, and the absence of a Noether current. We comment on recent literature where this symmetry is considered to be either absent or non-invertible. We end by recalling the DHR reconstruction theorem, which states 0-form symmetries cannot be non-invertible for d>2, and argue for a higher-form symmetry reconstruction theorem.

    ↳ hep-thhep-phSciPost Phys.(2025)·13 citations
25. 25*

    A small Universe

    Jean-Luc Lehners🇩🇪 · Jerome Quintin🇨🇦

    Many cosmological models assume or imply that the total size of the universe is very large, perhaps even infinite. Here we argue instead that the universe might be comparatively small, in fact not much larger than the currently observed size. A concrete implementation of this idea is provided by the no-boundary proposal, in combination with a plateau-shaped inflationary potential. In this model, opposing effects of the weighting of the wave function and of the criterion of allowability of the geometries conspire to favour small universes. We point out that a small size of the universe also fits well with swampland conjectures, and we comment on the relation with the dark dimension scenario.

    ↳ hep-thastro-ph.COgr-qchep-phPLB(2024)·15 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.