Fri·Oct 22, 2021Friday·October 22, 2021

1. 01*

   Dark Matter Freeze-In with a Heavy Mediator: Beyond the EFT Approach

   Evan Frangipane🇺🇸 · Stefania Gori🇺🇸 · Bibhushan Shakya🇩🇪

   We study dark matter freeze-in scenarios where the mass of the mediator particle that couples dark matter to the Standard Model is larger than the reheat temperature, TRH, in the early Universe. In such setups, the standard approach is to work with an effective field theory (EFT) where the mediator is integrated out. We examine the validity of this approach in various generic s- and t-channel mediator frameworks. We find that the EFT approach breaks down when the mediator mass is between one to two orders of magnitude larger than TRH due to various effects such as s-channel resonance, a small thermally-suppressed abundance of the mediator, or decays of Standard Model particles through loops induced by the mediator. This highlights the necessity of including these contributions in such dark matter freeze-in studies. We also discuss the collider phenomenology of the heavy mediators, which is qualitatively different from standard freeze-in scenarios. We highlight that, due to the low TRH, the Standard Model-dark matter coupling in these scenarios can be relatively larger than in standard freeze-in scenarios, improving the testability prospects of these setups.

   hep-phJHEP(2022)·15 citations
2. 02*

   Gauge Field Production and Schwinger Reheating in Runaway Axion Inflation

   Soichiro Hashiba🇯🇵 · Kohei Kamada🇯🇵 · Hiromasa Nakatsuka🇯🇵

   In a class of (pseudoscalar) inflation, inflationary phase is followed by a kination phase, where the Universe is dominated by the kinetic energy of the inflaton that runs away in a vanishing scalar potential. In this class of postinflationary evolution of the Universe, reheating of the Universe cannot be achieved by the inflaton particle decay, which requires its coherent oscillation in a quadratic potential. In this study, we explore the U(1) gauge field production through the Chern-Simons coupling between the pseudoscalar inflaton and the gauge field during the kination era and examine the subsequent pair-particle production induced by the amplified gauge field known as the Schwinger effect, which can lead to reheating of the Universe. We find that with a rough estimate of the Schwinger effect for the Standard Model hyper U(1) gauge field and subsequent thermalization of the pair-produced particles, a successful reheating of the Universe can be achieved by their eventual domination over the kinetic energy of the inflaton, with some reasonable parameter sets. This can be understood as a concrete realization of the "Schwinger reheating". Constraints from the later-time cosmology are also discussed.

   hep-phastro-ph.COhep-thJCAP(2022)·8 citations
3. 03*

   Fully heavy pentaquarks in quark models

   Ye Yan🇨🇳 · Yuheng Wu🇨🇳 · Xiaohuang Hu🇨🇳 · Hongxia Huang🇨🇳 · Jialun Ping🇨🇳

   The fully heavy pentaquarks $cccc\bar{c}$ and $bbbb\bar{b}$ are systematically investigated within the chiral quark model and quark delocalization color screening model. The results are consistent in both two moelds, and the effect of the channel-coupling is crucial for forming a bound state of the fully heavy pentaquark system. Three possible fully heavy pentaquarks are obtained, which are the $cccc\bar{c}$ state with $J^P=1/2^{-}$ and the mass of $7891.9\sim 7892.7$ MeV, the $bbbb\bar{b}$ state with $J^P=1/2^{-}$ and the mass of $23810.1\sim 23813.8$ MeV, and the $bbbb\bar{b}$ state with $J^P=3/2^{-}$ and the mass of $23748.2\sim 23752.3$ MeV. All these fully heavy pentaquark states are worth searching in future experiments.

   hep-phPRD(2022)·33 citations
4. 04*

   Conditions of naturalness and fine-tunings for type-I seesaw mechanism with four-zero texture

   Masaki J. S. Yang🇯🇵

   In this paper, we search for conditions that the mass matrix of light neutrinos $m_{\nu }$ is not a result of large cancellations for the type-I seesaw mechanism with four-zero texture. For the Yukawa matrix of neutrinos $Y_{\nu }$ and heavy Majorana mass matrix $M_R$, these conditions are written as $(Y_{\nu }{)}_{i2}\propto (m_{\nu }{)}_{i2}\Rightarrow (Y_{\nu }{)}_{i2}\propto (M_R{)}_{i2}$. We call them {\it alignment} conditions because they align the certain rows or columns of the three neutrino mass matrices. If these conditions do not hold, the large mixing in $m_{\nu }$ is a result of fine-tuning due to the cancellation of several terms. Then they are required from a viewpoint of naturalness. They give an explanation of the seesaw-invariance of four-zero texture, and place rough restrictions on flavor structures of neutrinos. Under these conditions, $Y_{\nu }$ must have a cascade hierarchy. For $M_R$, the 12 submatrix has a similar hierarchy as $Y_{\nu }$ and $m_{\nu }$. However, the 23 submatrix has a waterfall hierarchy without some fine-tuning. Therefore, it is likely that $Y_{\nu }$ and $M_R$ have qualitatively different flavor structures. Furthermore, since the conditions restrict CP phases of the matrix elements, they imply existence of a universal generalized CP symmetry in the neutrino sector.

   hep-phPTEP(2022)·3 citations
5. 05*

   Some Thoughts on (the Incompleteness of) the (Double) Differential Event Rates for Elastic WIMP-Nucleus Scattering in (Directional) Direct Dark Matter Detection Physics

   Chung-Lin Shan🇹🇼

   In this paper, we revisit the expressions for the (double) differential event rates for elastic WIMP-nucleus scattering and discuss some unusual thoughts on (the incompleteness of) the uses of these expressions in (directional) direct Dark Matter detection physics. Several not-frequently mentioned (but important) issues will be argued and demonstrated in detail.

   hep-phastro-ph.HEhep-ex1 citation
6. 06*

   Non-Hermiticity: a new paradigm for model building in particle physics

   Peter Millington🇬🇧

   Non-Hermitian quantum theories have been applied in many other areas of physics. In this note, I will briefly review recent developments in the formulation of non-Hermitian quantum field theories, highlighting features that are unique compared to Hermitian theories. I will touch upon their crucial discrete symmetries and how continuous symmetry properties are borne out, including Noether's theorem, the Goldstone theorem and the Englert-Brout-Higgs mechanism. As examples, I will describe a non-Hermitian supersymmetric theory, and draw attention to non-Hermitian deformations of (scalar) QED, the Higgs-Yukawa theory and flavour oscillations, with potential implications for non-Hermitian model building in the neutrino sector. Together, these results pave the way for a systematic programme for building non-Hermitian extensions of the Standard Model of particle physics.

   hep-phhep-thPoS(2022)·3 citations
7. 07*

   Cosmology of the companion-axion model: dark matter, gravitational waves, and primordial black holes

   Zhe Chen🇦🇺 · Archil Kobakhidze🇦🇺 · Ciaran A. J. O'Hare🇦🇺 · Zachary S. C. Picker🇦🇺 · Giovanni Pierobon🇦🇺

   The companion-axion model introduces a second QCD axion to rescue the Peccei-Quinn solution to the strong-CP problem from the effects of colored gravitational instantons. As in single-axion models, the two axions predicted by the companion-axion model are attractive candidates for dark matter. The model is defined by two free parameters, the scales of the two axions' symmetry breaking, so we can classify production scenarios in terms of the relative sizes of these two scales with respect to the scale of inflation. We study the cosmological production of companion-axion dark matter in order to predict windows of preferred axion masses, and calculate the relative abundances of the two particles. Additionally, we show that the presence of a second axion solves the cosmological domain wall problem automatically in the scenarios in which one or both of the axions are post-inflationary. We also suggest unique cosmological signatures of the companion-axion model, such as the production of a $\sim$10 nHz gravitational wave background, and $\sim 100M_{\odot }$ primordial black holes.

   hep-phastro-ph.COhep-thSciPost Phys.(2025)·21 citations
8. 08*

   WimPyDD: an object-oriented Python code for WIMP-nucleus scattering direct detection in virtually any scenario

   Gaurav Tomar🇩🇪 · Injun Jeong🇰🇷 · Sunghyun Kang🇰🇷 · Stefano Scopel🇰🇷

   We introduce WimPyDD, a modular, object-oriented and customisable Python code that accurately predicts the expected WIMP-nucleus scattering rates in WIMP direct-detection experiments including the response of the detector. WimPyDD utilises the framework of Galilean-invariant non-relativistic effective theory, allowing to handle an arbitrary number of effective operators, and can perform the calculation of the excepted rate in virtually any scenario, including inelastic scattering, WIMPs with an arbitrary spin, and a generic velocity distribution in the Galactic halo. The power and flexibility of WimPyDD is discussed in some explicit examples.

   hep-phJ.Phys.Conf.Ser.(2021)·1 citation
9. 09*

   Leptonic CP asymmetry and Light flavored scalar

   Yoshihiko Abe🇯🇵 · Toshimasa Ito🇯🇵 · Koichi Yoshioka🇯🇵

   We consider a situation where right-handed neutrinos couple to a light scalar which is possibly a Nambu-Goldstone boson resulting from high-energy symmetry breaking. Its coupling is typically complex-valued and flavor-dependent. In this work, we investigate the possibility of the leptonic asymmetry generation in the Universe from the right-handed neutrino decay to flavorful light scalar. Furthermore a new source of asymmetry generation from a single decay process is pointed out, which is characteristic of the present setting.

   hep-phJHEP(2023)·6 citations
10. 10*

    Interactions of the doubly charmed state $T_{cc}^{+}$ with a hadronic medium

    L. M. Abreu🇧🇷 · F. S. Navarra🇧🇷 · M. Nielsen🇧🇷 · H. P. L. Vieira🇧🇷

    We investigate the absorption and production processes of this new state in a hadronic medium, considering the reactions $T_{cc}^{+}\pi ,T_{cc}^{+}\rho \to D^{(\ast )}{D}^{(\ast )}$ and the corresponding inverse reactions. We use effective field Lagrangians to account for the couplings between light and heavy mesons, and give special attention to the form factors in the vertices. We calculate here for the first time the $T_{cc}^{+}-D-D^{\ast }$ form factor derived from QCD sum rules. The results are also obtained by testing widely utilized empirical form factors. The absorption cross sections are found to be larger than the production ones. We compare our results with the only existing estimate of these quantities, presented in a work of J.~Hong, S.~Cho, T.~Song and S.~H.~Lee, in which the authors employed the quasi-free approximation. We find cross sections which are one order of magnitude smaller.

    hep-phEPJC(2022)·28 citations
11. 11*

    Forward-backward correlations in proton-proton collisions at the LHC energy: A model based study

    Joyati Mondal🇮🇳 · Somnath Kar🇮🇳 · Hirak Koley🇮🇳 · Srijita Mukherjee🇮🇳 · Argha Deb🇮🇳 · Mitali Mondal🇮🇳

    Forward-backward (FB) multiplicity and momentum correlations of produced particles between symmetrically located pseudorapidity ($\eta$) intervals have been studied using the $p$QCD inspired EPOS3 model with and without hydrodynamical evolution of particles in proton-proton ($pp$) collisions at the center-of-mass energy, $\sqrt{s}=13$ TeV. The pseudorapidity-gap (${\eta }_{gap}$) dependence of FB correlation strength is compared with our previously published results at $\sqrt{s}=$ 0.9, 2.76 and 7 TeV. The study reveals that the general trends of FB correlation strength at $\sqrt{s}=13$ TeV are similar to our previous observations at lower center-of-mass energies. We also find that the $\delta \eta$-weightage average of FB correlation strength as a function of different center-of-mass energies ($\sqrt{s}=$ 0.9, 2.76, 7 and 13 TeV) tends to saturate at very high energy.

    hep-ph0 citations
12. 12*

    Lepton universality violation from neutral pion decays in $R_{K^{(\ast )}}$ measurements

    Dean J. Robinson🇺🇸

    I show that the neutral pion decay in $B\to K^{(\ast )}{\pi }^0\gamma$, with ${\pi }^0\to ee\gamma$, might generate large sources of lepton flavor universality violation (LFUV) in measurements of the ratios, $R_{K^{(\ast )}}$: If the photons in the $K^{(\ast )}ee\gamma \gamma$ final state are reconstructed as Bremsstrahlung, the recovered electron-positron invariant mass can be pushed into the $1$-$6$ GeV${}^2$ signal region, artificially enhancing the measured $B\to K^{(\ast )}ee$ branching ratio compared to $B\to K^{(\ast )}\mu \mu$. I present a conservative estimate and simulation of the $B\to K{\pi }^0\gamma$ LFUV background at LHCb, that together suggest this effect could reduce the recovered $R_K$ up to several percent. A reliable assessment of the size of this effect will require dedicated simulations within experimental frameworks themselves.

    hep-phPRD(2022)·4 citations
13. 13*

    Exploring Earth's Matter Effect in High-Precision Long-Baseline Experiments

    Masoom Singh🇮🇳 · Sanjib Kumar Agarwalla🇮🇳

    The Earth's matter effect is going to play a crucial role in measuring the unknown three-flavor neutrino oscillation parameters at high confidence level in future high-precision long-baseline experiments. We observe that owing to the new degeneracies among the most uncertain oscillation parameters (${\delta }_{CP},{\theta }_{23}$) and the average Earth's matter density (${\rho }_{avg}$) for the 1300 km baseline, the sensitivity of the upcoming Deep Underground Neutrino Experiment (DUNE) to establish Earth's matter effect reaches only about 2$\sigma$ C.L. for all possible choices of oscillation parameters. We notice that the current uncertainty in ${\delta }_{CP}$ degrades the measurement of ${\rho }_{avg}$ more as compared to ${\theta }_{23}$. To lift these degeneracies, we explore the possible complementarity between DUNE and Tokai to Hyper-Kamiokande (T2HK/JD) facility with a second detector in Korea, popularly known as T2HKK or JD+KD setup. While DUNE uses wide-band beam with on-axis detector, T2HKK setup plans to use narrow-band beam with two off-axis detectors: one in Japan and other in Korea. We exhibit how the high-precision measurement of ${\delta }_{CP}$ in JD+KD setup and the information on ${\rho }_{avg}$ coming from DUNE can reduce the impact of these degeneracies in both (${\rho }_{avg}-{\delta }_{CP}$) and (${\rho }_{avg}-{\theta }_{23}$) planes. We show that the combined data from DUNE and JD+KD setups can establish Earth's matter effect at more than 6$\sigma$ C.L. irrespective of both the choices of mass hierarchy: normal (NH) and inverted (IH), ${\delta }_{CP}$, and ${\theta }_{23}$. With the help of this combined data set, we can measure the average matter density (${\rho }_{avg}$) with a relative 1$\sigma$ precision of around 11.2% (9.4%) assuming true NH (IH) and ${\delta }_{CP}=-90^{\circ }/90^{\circ }$.

    hep-phhep-exphysics.ins-detPoS(2022)·3 citations
14. 14*

    Two-loop corrections to the Higgs trilinear coupling in classically scale-invariant theories

    Johannes Braathen🇩🇪 · Shinya Kanemura🇯🇵 · Makoto Shimoda🇯🇵

    The Higgs trilinear coupling is a crucial tool to investigate the structure of the Higgs sector and the nature of the electroweak phase transition, and to search for indirect signs of New Physics. Classical scale invariance (CSI) is an attractive concept for BSM model building, explaining the apparent alignment of the Higgs sector and potentially relating to the hierarchy problem. A particularly interesting feature of CSI theories is that, at one loop, they universally predict the Higgs trilinear coupling to deviate by 67% from the SM prediction at tree level. This result is however modified at two loops, and we present here results from the first explicit computation of two-loop corrections to the Higgs trilinear coupling in classically scale-invariant BSM models. Taking as example a CSI variant of the Two-Higgs-Doublet Model, we show that the inclusion of two-loop effects allows distinguishing different scenarios with CSI, even though the requirement of correctly reproducing the mass of the Higgs boson, as well as unitarity, severely restrict the possible values of the Higgs trilinear coupling.

    hep-phPoS(2022)·1 citation
15. 15*

    Precision calculation of neutrino evolution in the early Universe

    Julien Froustey🇫🇷

    In the primordial Universe, neutrino decoupling occurs only slightly before electron-positron annihilations. This leads notably to an increased neutrino energy density compared to the standard instantaneous decoupling approximation, parametrized by the effective number of neutrino species $N_{\mathrm{eff}}$. A precise calculation of neutrino evolution is needed to assess its consequences during the later cosmological stages, and requires to take into account multiple effects such as neutrino oscillations, which represents a genuine numerical challenge. Recently, several key improvements have allowed such a precise numerical calculation, leading to the new reference value $N_{\mathrm{eff}}=3.0440$.

    hep-phastro-ph.COJ.Phys.Conf.Ser.(2021)·3 citations
16. 16*

    The phenomenological cornucopia of SU(3) exotica

    Linda M. Carpenter🇺🇸 · Taylor Murphy🇺🇸 · Tim M. P. Tait🇺🇸

    We introduce an effort to catalog the gauge-invariant interactions of Standard Model (SM) particles and new fields in a variety of representations of the SM color gauge group $\text{SU}(3{)}_{\text{c}}$. In this first installment, we direct this effort toward fields in the six-dimensional (sextet, $6$) representation. We consider effective operators of mass dimension up to seven (comprehensively up to dimension six), featuring both scalar and fermionic color sextets. We use an iterative tensor-product method to identify the color invariants underpinning such operators, emphasizing structures that have received little attention to date. In order to demonstrate the utility of our approach, we study a simple but novel model of color-sextet fields at the Large Hadron Collider (LHC). We compute cross sections for an array of new production channels enabled by our operators, including single-sextet production and sextet production in association with photons or leptons. We also discuss dijet-resonance constraints on a sextet fermion. This example shows that there remains a wide array of fairly minimal but well motivated and unexplored models with extended strong sectors as we await the high-luminosity LHC.

    hep-phPRD(2022)·23 citations
17. 17*

    Analytic results for Sudakov form factors in QCD

    Markus A. Ebert🇩🇪

    Sudakov form factors appear ubiquitously in factorized cross sections where they allow one to resum large logarithms to all orders in perturbation theory. Their exact evaluation requires numerical integrals over anomalous dimensions, which in practice can hamper efficiency. Alternatively, one can use approximate analytic solutions, which provide fast evaluation at the cost of numerical precision and loss of properties such as renormalization group invariance. We provide an exact analytic expression of the QCD Sudakov form factor which allows one to obtain fast and numerically exact results.

    hep-phJHEP(2022)·17 citations
18. 18*

    Axial-vector exchange contribution to the Hyperfine Splitting

    Alejandro Miranda🇲🇽 · Pablo Roig🇲🇽 · Pablo Sanchez-Puertas🇪🇸

    We revisit the contribution of axial-vector mesons to the hyperfine splitting of muonic hydrogen. We focus our attention on the doubly-virtual asymptotic behavior of the relevant form factors of axial-vector mesons, together with their coupling to nucleons based on resonance saturation and short-distance constraints. Among others, we find significant differences with respect to previous studies, including an opposite sign and a $\sim 50\%$ effect of the doubly-virtual high-energy behavior.

    hep-phPRD(2022)·16 citations
19. 19*

    The $\gamma \pi \to \pi \pi$ anomaly from lattice QCD and dispersion relations

    Malwin Niehus🇩🇪 · Martin Hoferichter🇨🇭 · Bastian Kubis🇩🇪

    We propose a formalism to extract the $\gamma \pi \to \pi \pi$ chiral anomaly $F_{3\pi }$ from calculations in lattice QCD performed at larger-than-physical pion masses. To this end, we start from a dispersive representation of the ${\gamma }^{(\ast )}\pi \to \pi \pi$ amplitude, whose main quark-mass dependence arises from the $\pi \pi$ scattering phase shift and can be derived from chiral perturbation theory via the inverse-amplitude method. With parameters constrained by lattice calculations of the $P$-wave phase shift, we use this combination of dispersion relations and effective field theory to extrapolate two recent ${\gamma }^{(\ast )}\pi \to \pi \pi$ calculations in lattice QCD to the physical point. Our formalism allows us to extract the radiative coupling of the $\rho (770)$ meson and, for the first time, the chiral anomaly $F_{3\pi }=38(16)(11){\text{GeV}}^{-3}$. The result is consistent with the chiral prediction albeit within large uncertainties, which will improve in accordance with progress in future lattice-QCD computations.

    hep-phhep-exhep-latnucl-thJHEP(2021)·35 citations
20. 20*

    Electromagnetic conductivity of quark-gluon plasma at non-zero baryon density

    N. Astrakhantsev🇨🇭 · V.V. Braguta🇷🇺 · M. Cardinali🇮🇹 · M. D'Elia🇮🇹 · L. Maio🇮🇹 · F. Sanfilippo🇮🇹 · A. Trunin🇷🇺 · A. Vasiliev🇷🇺

    In this preprint we present our results on the study of the electromagnetic conductivity in dense quark-gluon plasma obtained within lattice simulations with $N_f=2+1$ dynamical quarks. We employ stout improved rooted staggered quarks at the physical point and the tree-level Symanzik improved gauge action. The simulations are performed at imaginary baryon chemical potential, and the Tikhonov regularisation method is used to extract the conductivity from current-current correlators. Our results indicate an increase of QGP electromagnetic conductivity with real baryon density, and this dependence is quite strong.

    ↳ hep-lathep-phhep-thPoS(2022)·8 citations
21. 21*

    Entanglement Structures in Quantum Field Theories: Negativity Cores and Bound Entanglement in the Vacuum

    Natalie Klco🇺🇸 · D. H. Beck🇺🇸 · Martin J. Savage🇺🇸

    The many-body entanglement between two finite (size-$d$) disjoint vacuum regions of non-interacting lattice scalar field theory in one spatial dimension -- a $(d_A\times d_B{)}_{\mathrm{mixed}}$ Gaussian continuous variable system -- is locally transformed into a tensor-product "core" of $(1_A\times 1_B{)}_{\mathrm{mixed}}$ entangled pairs. Accessible entanglement within these core pairs exhibits an exponential hierarchy, and as such identifies the structure of dominant region modes from which vacuum entanglement could be extracted into a spatially separated pair of quantum detectors. Beyond the core, remaining modes of the "halo" are determined to be AB-separable in isolation, as well as separable from the core. However, state preparation protocols that distribute entanglement in the form of $(1_A\times 1_B{)}_{\mathrm{mixed}}$ core pairs are found to require additional entanglement in the halo that is obscured by classical correlations. This inaccessible (bound) halo entanglement is found to mirror the accessible entanglement, but with a step behavior as the continuum is approached. It remains possible that alternate initialization protocols that do not utilize the exponential hierarchy of core-pair entanglement may require less inaccessible entanglement. Entanglement consolidation is expected to persist in higher dimensions and may aid classical and quantum simulations of asymptotically free gauge field theories, such as quantum chromodynamics.

    ↳ quant-phhep-lathep-phhep-th+1PRA(2023)·35 citations
22. 22*

    BICEP/Keck and Cosmological Attractors

    Renata Kallosh🇺🇸 · Andrei Linde🇺🇸

    We discuss implications of the latest BICEP/Keck data release for inflationary models, with special emphasis on the cosmological attractors which can describe all presently available inflation-related observational data. These models are compatible with any value of the tensor to scalar ratio $r$, all the way down to $r=0$. Some of the string theory motivated models of this class predict $10^{-3}\le r\le 10^{-2}$. The upper part of this range can be explored by the ongoing BICEP/Keck observations.

    ↳ astro-ph.COgr-qchep-phhep-thJCAP(2021)·53 citations
23. 23*

    Reconciling multi-messenger constraints with chiral symmetry restoration

    Michał Marczenko🇵🇱 · Krzysztof Redlich🇵🇱 · Chihiro Sasaki🇵🇱

    We analyze the recent astrophysical constraints in the context of a hadronic equation of state (EoS), in which the baryonic matter is subject to chiral symmetry restoration. We show that with such EoS it is possible to reconcile the modern constraints on the neutron star (NS) mass, radius, and tidal deformability (TD). We find that the softening of the EoS, required by the TD constraint of a canonical $1.4M_{\odot }$ NS, followed by a subsequent stiffening, required by the $2M_{\odot }$ constraint, is driven by the appearance of $\Delta$ matter due to partial restoration of chiral symmetry. Consequently, a purely hadronic EoS that accounts for the fundamental properties of quantum chromodynamics linked to the dynamical emergence of parity doubling with degenerate masses of nucleons and $\Delta$ resonances can be fully consistent with multi-messenger data. Therefore, with the present constraints on the EoS, the conclusion about the existence of the quark matter in the stellar core may still be premature.

    ↳ nucl-thastro-ph.HEhep-phApJL(2022)·26 citations
24. 24*

    Generalized uncertainty principle or curved momentum space?

    Fabian Wagner🇵🇱

    The concept of minimum length, widely accepted as a low-energy effect of quantum gravity, manifests itself in quantum mechanics through generalized uncertainty principles. Curved momentum space, on the other hand, is at the heart of similar applications such as doubly special relativity. We introduce a duality between theories yielding generalized uncertainty principles and quantum mechanics on nontrivial momentum space. In particular, we find canonically conjugate variables which map the former into the latter. In that vein, we explicitly derive the vielbein corresponding to a generic generalized uncertainty principle in $d$ dimensions. Assuming the predominantly used quadratic form of the modification, the curvature tensor in momentum space is proportional to the noncommutativity of the coordinates in the modified Heisenberg algebra. Yet, the metric is non-Euclidean even in the flat case corresponding to commutative space, because the resulting momentum basis is noncanonical. These insides are used to constrain the curvature and the deviation from the canonical basis.

    ↳ gr-qchep-phquant-phPRD(2021)·45 citations
25. 25*

    CaloFlow II: Even Faster and Still Accurate Generation of Calorimeter Showers with Normalizing Flows

    Claudius Krause🇺🇸 · David Shih🇺🇸

    Recently, we introduced CaloFlow, a high-fidelity generative model for GEANT4 calorimeter shower emulation based on normalizing flows. Here, we present CaloFlow v2, an improvement on our original framework that speeds up shower generation by a further factor of 500 relative to the original. The improvement is based on a technique called Probability Density Distillation, originally developed for speech synthesis in the ML literature, and which we develop further by introducing a set of powerful new loss terms. We demonstrate that CaloFlow v2 preserves the same high fidelity of the original using qualitative (average images, histograms of high level features) and quantitative (classifier metric between GEANT4 and generated samples) measures. The result is a generative model for calorimeter showers that matches the state-of-the-art in speed (a factor of $10^4$ faster than GEANT4) and greatly surpasses the previous state-of-the-art in fidelity.

    ↳ physics.ins-detcs.LGhep-exhep-ph+1PRD(2023)·119 citations
26. 26*

    Chiral anomalous processes in magnetospheres of pulsars and black holes

    E. V. Gorbar🇺🇦 · I. A. Shovkovy🇺🇸

    We propose that chirally asymmetric plasma can be produced in the gap regions of the magnetospheres of pulsars and black holes. We show that, in the case of supermassive black holes situated in active galactic nuclei, the chiral charge density and the chiral chemical potential are very small and unlikely to have any observable effects. In contrast, the chiral asymmetry produced in the magnetospheres of magnetars can be substantial. It can trigger the chiral plasma instability that, in turn, can lead to observable phenomena in magnetars. In particular, the instability should trigger circularly polarized electromagnetic radiation in a wide window of frequencies, spanning from radio to near-infrared. As such, the produced chiral charge has the potential to affect some features of fast radio bursts.

    ↳ astro-ph.HEhep-phnucl-thEPJC(2022)·17 citations
27. 27*

    Black Hole Shadow in Symmergent Gravity

    İrfan Çimdiker🇹🇷 · Durmuş Demir🇹🇷 · Ali Övgün🇹🇷

    Symmergent gravity is the $R+R^2$ gravity theory which emerges in a way restoring gauge symmetries broken explicitly by the ultraviolet cutoff in effective field theories. To test symmergent gravity we construct novel black hole solutions in four dimensions, and study their shadow in the vacuum as well as plasma medium. Our detailed analyses show that the horizon radius, Hawking temperature, Bekenstein-Hawking entropy, shadow angular radius, and photon deflection angle are sensitive probes of the symmergent gravity and particle spectrum of the underlying quantum field theory.

    ↳ gr-qcastro-ph.HEhep-phhep-thPhys.Dark Univ.(2021)·84 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.