Thu·Dec 31, 2020Thursday·December 31, 2020

1. 01*

   Baryogenesis from ultralight primordial black holes and strong gravitational waves from cosmic strings

   Satyabrata Datta🇮🇳 · Ambar Ghosal🇮🇳 · Rome Samanta🇨🇿

   Ultralight primordial black holes (PBHs)($\lesssim 10^9$g) completely evaporate via Hawking radiation (HR) and produce all the particles in a given theory regardless of their other interactions. If the right handed (RH) neutrinos are produced from PBH evaporation, successful baryogenesis via leptogenesis predicts mass scale of RH neutrinos as well as black holes. We show that, given the lepton number violation (generation of RH neutrino masses) in the theory is a consequence of a gauged $U(1)$ breaking which is then followed by the formation of PBHs, a network of cosmic strings naturally gives rise to strong stochastic gravitational wave (GW) signal at the sensitivity level of pulsar timing arrays (PTA) and LIGO5. Besides, due to a transient period of black hole domination in the early universe, for which baryon asymmetry is independent of initial PBH density, a break in the GW spectra occurs around MHz frequency. Therefore, to observe the break along with the usual GW signal by the emission of gravitons via HR, GW detectors at higher frequencies are called for. The recent finding by the NANOGrav PTA of a stochastic common spectrum process (interpreted as GWs) across many pulsars is in tension with PBH baryogenesis for large cosmic string loops ($\alpha \simeq 0.1$).

   hep-phastro-ph.COgr-qcJCAP(2021)·122 citations
2. 02*

   Nonrelativistic Effective Field Theory with a Resonance Field

   J. B. Habashi🇺🇸 · S. Fleming🇺🇸 · U. van Kolck🇫🇷

   We discuss shallow resonances in the nonrelativistic scattering of two particles using an effective field theory (EFT) that includes an auxiliary field with the quantum numbers of the resonance. We construct the manifestly renormalized scattering amplitude up to next-to-leading order in a systematic expansion. For a narrow resonance, the amplitude is perturbative except in the immediate vicinity of the resonance poles. It naturally has a zero in the low-energy region, analogous to the Ramsauer-Townsend effect. For a broad resonance, the leading-order amplitude is nonperturbative almost everywhere in the regime of validity of the EFT. We regain the results of an EFT without the auxiliary field, which is equivalent to the effective-range expansion with large scattering length and effective range. We also consider an additional fine tuning leading to a low-energy amplitude zero even for a broad resonance. We show that in all cases the requirement of renormalizability when the auxiliary field is not a ghost ensures the resonance poles are in the lower half of the complex momentum plane, as expected by other arguments. The systematic character of the EFT expansion is exemplified with a toy model serving as underlying theory.

   hep-phnucl-thquant-phEPJA(2021)·21 citations
3. 03*

   Contributions for the kaon pair from $\rho (770)$, $\omega (782)$ and their excited states in the $B\to K\bar{K}h$ decays

   Wen-Fei Wang🇨🇳

   We study the resonance contributions for the kaon pair originating from the intermediate states $\rho (770,1450,1700)$ and $\omega (782,1420,1650)$ for the three-body hadronic decays $B\to K\bar{K}h$ in the perturbative QCD approach, where $h=(\pi ,K)$. The branching fractions of the virtual contributions for $K\bar{K}$ from the Breit-Wigner formula tails of $\rho (770)$ and $\omega (782)$ which have been ignored in experimental and theoretical studies for these decays are found larger than the corresponding contributions from the resonances $\rho (1450,1700)$ and $\omega (1420,1650)$. The differential branching fractions for $B\to \rho (770)h\to K\bar{K}h$ and $B\to \omega (782)h\to K\bar{K}h$ are found nearly unaffected by the quite different values of the full widths for $\rho (770)$ and $\omega (782)$ in this paper. The predictions in this work for the branching fractions of the quasi-two-body decays $B^{+}\to {\pi }^{+}\rho (1450{)}^0\to {\pi }^{+}{K}^{+}{K}^{-}$ and $B^{+}\to {\pi }^{+}\rho (1450{)}^0\to {\pi }^{+}{\pi }^{+}{\pi }^{-}$ meet the requirement of $SU(3)$ symmetry relation.

   hep-phhep-exPRD(2021)·22 citations
4. 04*

   Density spikes near black holes in self-interacting dark matter halos and indirect detection constraints

   Gerardo Alvarez🇺🇸 · Hai-Bo Yu🇺🇸

   Self-interacting dark matter (SIDM) naturally gives rise to a cored isothermal density profile, which is favored in observations of many dwarf galaxies. The dark matter distribution in the presence of a central black hole in an isothermal halo develops a density spike with a power law of $r^{-7/4}$, which is shallower than $r^{-7/3}$ as expected for collisionless dark matter (CDM). Thus, indirect detection constraints on dark matter annihilations from the density spike could be relaxed in SIDM. Taking the most dense satellite galaxy of the Milky Way Draco as an example, we derive upper limits on the annihilation cross section and the black hole mass for both SIDM and CDM halos. For the former case, Draco could host an intermediate mass black hole even if dark matter is composed of thermal relics. We further explore the constraints from the Milky Way and M87, which host supermassive black holes, and show the upper limits on the annihilation cross section are significantly weakened in SIDM. Our results also indicate that the Event Horizon Telescope could provide a unique test of SIDM spikes.

   hep-phPRD(2021)·33 citations
5. 05*

   Global Analysis of hadronic two-body B decays in the perturbative QCD approach

   Jun Hua🇨🇳 · Hsiang-nan Li🇹🇼 · Cai-Dian Lu🇨🇳 · Wei Wang🇨🇳 · Zhi-Peng Xing🇨🇳

   Based on the flavor structure of four-quark effective operators, we develop an automatic computation program to calculate hadronic two-body $B$ meson decay amplitudes, and apply it to their global analysis in the perturbative QCD (PQCD) approach. Fitting the PQCD factorization formulas for $B\to PP,VP$ decays at leading order in the strong coupling ${\alpha }_s$ to measured branching ratios and direct CP asymmetries, we determine the Gegenbauer moments in light meson light-cone distribution amplitudes (LCDAs). It is found that most of the fitted Gegenbauer moments of the twist-2 and twist-3 LCDAs for the pseudoscalar meson $P$ ($P=\pi$, $K$) and vector meson $V$ ($V=\rho$, $K^{\ast }$) agree with those derived in QCD sum rules. The shape parameter for the $B_s$ meson distribution amplitude and the weak phase ${\varphi }_3(\gamma )=(75.1\pm 2.9{)}^{\circ }$ consistent with the value in Particle Data Group are also obtained. It is straightforward to extend our analysis to higher orders and higher powers in the PQCD approach, and to the global determination of LCDAs for other hadrons.

   hep-phPRD(2021)·29 citations
6. 06*

   Precise predictions for electroweak $t\bar{t}$ production at the LHC in models with flavour non-diagonal $Z^{\prime }$ boson couplings and $W^{\prime }$ bosons

   M.M. Altakach🇫🇷 · T. Ježo🇩🇪 · M. Klasen🇩🇪 · J.-N. Lang🇨🇭 · I. Schienbein🇫🇷

   We report on our re-calculation of electroweak top-quark pair production in Standard Model extensions with extra heavy neutral and charged spin-1 particles at the LHC with substantial improvements. In particular, we allow for flavour--non-diagonal $Z^{\prime }$ couplings and take into account non-resonant production in the Standard Model and beyond. As in our previous work we include NLO QCD corrections and match to parton showers with the POWHEG method fully taking into account the Standard Model and new physics interference effects. We consider the Sequential Standard Model, the Topcolour model as well as the Third Family Hypercharge Model featuring non-flavour diagonal $Z^{\prime }$ couplings which has been proposed to explain the anomalies in $B$ decays. Numerical results for $t\bar{t}$ cross sections at hadron colliders with $\sqrt{s}$ of up to 100 TeV are presented. We also investigate the numerical impact of the new non-resonant contributions.

   hep-phhep-exPoS(2021)·3 citations
7. 07*

   Confinement of Fermions in Tachyon Matter at Finite Temperature

   Adamu Issifu🇧🇷 · Julio C.M. Rocha🇧🇷 · Francisco A. Brito🇧🇷

   We study a phenomenological model that mimics the characteristics of QCD theory at finite temperature. The model involves fermions coupled with a modified Abelian gauge field in a tachyon matter. It reproduces some important QCD features such as, confinement, deconfinement, chiral symmetry and quark-gluon-plasma (QGP) phase transitions. The study may shed light on both light and heavy quark potentials and their string tensions. Flux-tube and Cornell potentials are developed depending on the regime under consideration. Other confining properties such as scalar glueball mass, gluon mass, glueball-meson mixing states, gluon and chiral condensates are exploited as well. The study is focused on two possible regimes, the ultraviolet (UV) and the infrared (IR) regimes.

   hep-phhep-thAdv.High Energy Phys.(2021)·5 citations
8. 08*

   Filtered pseudo-scalar dark matter and gravitational waves from first order phase transition

   Wei Chao🇨🇳 · Xiu-Fei Li🇨🇳 · Lei Wang🇨🇳

   If dark matter (DM) acquires mass during a first order phase transition, there will be a filtering-out effect when DM enters the expanding bubble. In this paper we study the filtering-out effect for a pseudo-scalar DM, whose mass may partially come from a first order phase transition in the hidden sector. We calculate the ratio of DM that may enter the bubble for various bubble wall velocities as well as various status of DM (in the thermal equilibrium, or out of the thermal equilibrium) at the time of phase transition, which results in small penetration rate that may affect the final relic abundance of the DM. We further study the stochastic gravitational wave signals emitted by the hidden sector phase transition at the space-based interferometer experiments as the smoking-gun of this model.

   hep-phJCAP(2021)·44 citations
9. 09*

   Minimal and non-minimal Universal Extra Dimension models in the light of LHC data at 13 TeV

   Avnish🇮🇳 · Kirtiman Ghosh🇮🇳 · Tapoja Jha🇮🇳 · Saurabh Niyogi🇮🇳

   Universal Extra Dimension (UED) is a well-motivated and well-studied scenario. One of the main motivations is the presence of a dark matter (DM) candidate namely, the lightest level-1 Kaluza-Klein (KK) particle (LKP), in the particle spectrum of UED. The minimal version of UED (mUED) scenario is highly predictive with only two parameters namely, the radius of compactification and cut-off scale, to determine the phenomenology. Therefore, stringent constraint results from the WMAP/PLANCK measurement of DM relic density (RD) of the universe. The production and decays of level-1 quarks and gluons in UED scenarios give rise to multijet final states at the Large Hadron Collider (LHC) experiment. We study the ATLAS search for multijet plus missing transverse energy signatures at the LHC with 13 TeV center of mass energy and 139 inverse femtobarn integrated luminosity. In view of the fact that the DM RD allowed part of mUED parameter-space has already been ruled out by the ATLAS multijet search, we move on to a less restricted version of UED namely, the non-minimal UED (nmUED), with non-vanishing boundary-localized terms (BLTs). The presence of BLTs significantly alters the dark matter as well as the collider phenomenology of nmUED. We obtain stringent bounds on the BLT parameters from the ATLAS multijet plus missing transverse energy search.

   hep-phhep-exhep-thPRD(2021)·10 citations
10. 10*

    Accurate prediction of the ${\varphi }_{\eta }^{\ast }$ distribution for the forward Z boson production in pp collisions through NNLO+N${}^3$LL

    Kadir Ocalan🇹🇷

    This paper presents a phenomenological study for the differential cross section of the forward Z boson production in leptonic decay channels as a function of the angular variable ${\varphi }_{\eta }^{\ast }$ in proton-proton collisions. The ${\varphi }_{\eta }^{\ast }$ distribution is predicted for the forward pseudorapidity region $2.0<{\eta }_l<4.5$ of the decay leptons at center-of-mass energies 8, 13, and 14 TeV. Accurate prediction of the ${\varphi }_{\eta }^{\ast }$ distribution is achieved by means of the state-of-the-art calculations including fixed-order perturbative QCD and large logarithmic corrections. The predicted distributions are obtained by employing the resummation either at next-to-next-to-leading logarithmic (NNLL) or next-to-NNLL (N${}^3$LL) accuracy which is matched to the perturbative QCD calculation at next-to-next-to-leading order (NNLO) accuracy, that is at NNLO+NNLL and NNLO+N${}^3$LL, respectively. The Z boson ${\varphi }_{\eta }^{\ast }$ variable is experimentally preferable as it has been measured more precisely than the Z boson transverse momentum though both variables probe the same physics, thereby an accurate description of the ${\varphi }_{\eta }^{\ast }$ variable is required by using theoretical predictions at both NNLO+NNLL and NNLO+N${}^3$LL accuracies. The matched predictions are compared with the available 8 TeV and 13 TeV measurements by the LHCb experiment at the LHC and found to be in good agreement. The 14 TeV predicted distributions at both NNLO+NNLL and NNLO+N${}^3$LL are also reported. In all the predicted results, the NNLO+N${}^3$LL provides more improved accuracy for the reliable description of the ${\varphi }_{\eta }^{\ast }$ distribution throughout its entire phase space region.

    hep-phJ.Korean Phys.Soc.(2021)·1 citation
11. 11*

    Chiral separation effect catalyzed by heavy impurities

    Daiki Suenaga🇯🇵 · Yasufumi Araki🇯🇵 · Kei Suzuki🇯🇵 · Shigehiro Yasui🇯🇵

    We investigate the influence of Kondo effect, namely, the nonperturbative effect induced by heavy impurities, on the chiral separation effect (CSE) in quark matter. We employ a simple effective model incorporating the Kondo condensate made of a light quark and a heavy quark, and compute the response function of axial current to the magnetic field in static limit and dynamical limit. As a result, we find that the Kondo effect catalyzes the CSE in both the limits, and particularly the CSE in dynamical limit can be enhanced by a factor of approximately three. Our findings clearly show that the presence of heavy impurities in quark matter can play an important role in the transport phenomena of light quarks induced by a magnetic field.

    hep-phcond-mat.mes-hallnucl-thPRD(2021)·9 citations
12. 12*

    Heavy dark matter and Gravitational waves

    Xin Deng🇨🇳 · Xuewen Liu🇨🇳 · Jing Yang🇨🇳 · Ruiyu Zhou🇨🇳 · Ligong Bian🇨🇳

    Domain walls can form after breakdown of a discrete symmetry induced by first-order phase transition, we study the heavy dark matter produced around the temperature of the phase transition that yields the breakdown of a ${\mathbb{Z}}_3$ symmetry. The generated gravitational waves by domain walls decay is found to be able to probed by the Pulsar Timing Arrays, and the future Square Kilometer Array.

    hep-phastro-ph.COPRD(2021)·17 citations
13. 13*

    Perturbative Charm Production and the Prompt Atmospheric Neutrino Flux in light of RHIC and LHC

    Atri Bhattacharya🇧🇪 · Rikard Enberg🇸🇪 · Mary Hall Reno🇺🇸 · Ina Sarcevic🇺🇸 · Anna Stasto🇺🇸

    Prompt neutrinos due to the decay of charmed mesons produced in the atmosphere from cosmic-ray and atmospheric nuclei interactions may be a significant source of background to ultra-high energy neutrino searches above 10 TeV. We re-evaluate this flux using updated charm production cross-sections based on QCD parameters, the charm quark mass, and the range for the factorization and renormalization scales that provide the best description of this data at fixed target experiments, at RHIC, and at LHC. We find that the prompt neutrino flux is reduced from previous results in the literature by a factor between two and eight, depending on the energy. We discuss the implications of our results for current IceCube data.

    hep-phPoS(2021)·1 citation
14. 14*

    Minimal models for $g-2$ and dark matter confront asymptotic safety

    Kamila Kowalska🇵🇱 · Enrico Maria Sessolo🇵🇱

    We use the framework of asymptotic safety above the Planck scale to constrain the parameter space of simple models of new physics that can accommodate the measured value of the anomalous magnetic moment of the muon and the relic density of dark matter. We couple parametrically to the trans-Planckian quantum physics a set of SU(2)$\times$U(1) invariant extensions of the Standard Model, each comprising an inert scalar field and one pair of colorless fermions that communicate to the muons through Yukawa-type interactions. The presence of an interactive UV fixed point in the system of gauge and Yukawa couplings imposes a set of boundary conditions at the Planck scale, which allow one to derive unique phenomenological predictions in each case and distinguish the different representations of the gauge group from one another. We apply to the models constraints from the $h\to \mu \mu$ signal strength at ATLAS and CMS, direct LHC searches for electroweak production with leptons and missing energy in the final state, and the dark matter relic density. We find that they further restrict the available parameter space.

    hep-phPRD(2021)·65 citations
15. 15*

    Towards Colour Flow Evolution at Two Loops

    Simon Plätzer🇦🇹 · Ines Ruffa🇦🇹

    We calculate the two-loop and one-loop/one-emission contributions required for soft gluon evolution at the next-to-leading order. The colour structures are expressed in the colour flow basis, and the kinematic dependence and loop integrals are expressed in terms of multiple cuts and phase-space-like integrals. This directly allows to use them in the resummation of non-global observables and improved parton shower algorithms beyond the leading order and beyond the leading colour limit. Within the colour flow basis it becomes apparent that correlations beyond a dipole picture emerge even in colour-diagonal elements of the virtual corrections.

    hep-phJHEP(2021)·28 citations
16. 16*

    Inflation, reheating, leptogenesis and bounds on soft supersymmetry breaking parameters

    Imtiyaz Ahmad Bhat🇮🇳 · Girish Kumar Chakravarty🇮🇳 · Rathin Adhikari🇮🇳

    In the no-scale supergravity with Type-I Seesaw model of Non-minimal supersymmetric standard model (NMSSM), we have analysed inflation, reheating and leptogenesis. A no-scale supergravity realization of Starobinsky model of inflation in simple Wess-Zumino model have been shown earlier by Ellis et al. Here we show a no-scale supergravity realization of Starobinsky model of inflation in Type-I Seesaw framework of NMSSM. In this framework an appropriate choice of no-scale Kähler potential results in Starobinsky like plateau inflation along a Higgs-sneutrino $D$-flat direction consistent with the CMB observations. In leptogenesis, the soft-breaking trilinear and bilinear terms play important role. Using conditions for non-thermal contribution to $CP$ asymmetry and successful leptogenesis together with the appropriate reheating at the end of inflation, we have obtained important constraints on the soft supersymmetry breaking parameters.

    hep-phastro-ph.CO2 citations
17. 17*

    Light Dark Matter through Resonance Scanning

    Djuna Croon🇨🇦 · Gilly Elor🇺🇸 · Rachel Houtz🇬🇧 · Hitoshi Murayama🇺🇸 · Graham White🇯🇵

    We propose a new out-of-equilibrium production mechanism of light dark matter: resonance scanning. If the dark matter mass evolved in the early Universe, resonant production may have occurred for a wide range of light dark matter masses today. We show that the dark matter relic abundance may be produced through the Higgs portal, in a manner consistent with current experimental constraints.

    hep-phPRD(2022)·19 citations
18. 18*

    Flavor-changing Majoron interactions with leptons

    Yu Cheng🇨🇳 · Cheng-Wei Chiang🇹🇼 · Xiao-Gang He🇹🇼 · Jin Sun🇨🇳

    When the Standard Model Higgs sector is extended with a complex singlet that breaks global lepton number symmetry spontaneously, a massless Goldstone boson called the Majoron J arises. In addition to increasing Higgs invisible decay through mixing, the Majoron can generally have flavor-changing interactions with fermions. We find that type-III seesaw model poses such interesting properties with both charged leptons and neutrinos. This opens up new channels to search for the Majoron. We use the experimental data such as muonium-anti-muonium oscillation and flavor-changing neutrino and charged lepton decays to put constraints on the couplings. As a novel way to reveal the chiral properties of these interactions, we propose an experimentally measurable polarization asymmetry of flavor-changing l to l' J decays.

    hep-phhep-exPRD(2021)·12 citations
19. 19*

    Feynman Integrals and Scattering Amplitudes from Wilson Loops

    Song He🇨🇳 · Zhenjie Li🇨🇳 · Qinglin Yang🇨🇳 · Chi Zhang🇩🇰

    We study Feynman integrals and scattering amplitudes in $\mathcal{N}=4$ super-Yang-Mills by exploiting the duality with null polygonal Wilson loops. Certain Feynman integrals, including one-loop and two-loop chiral pentagons, are given by Feynman diagrams of a supersymmetric Wilson loop, where one can perform loop integrations and be left with simple integrals along edges. As the main application, we compute analytically for the first time, the symbol of the generic ($n\ge 12$) double pentagon, which gives two-loop MHV amplitudes and components of NMHV amplitudes to all multiplicities. We represent the double pentagon as a two-fold $\mathrm{d}\log$ integral of a one-loop hexagon, and the non-trivial part of the integration lies at rationalizing square roots contained in the latter. We obtain a remarkably compact "algebraic words" which contain $6$ algebraic letters for each of the $16$ square roots, and they all nicely cancel in combinations for MHV amplitudes and NMHV components which are free of square roots. In addition to $96$ algebraic letters, the alphabet consists of $152$ dual conformal invariant combinations of rational letters.

    ↳ hep-thhep-phPRL(2021)·31 citations
20. 20*

    Multiple Series Representations of $N$-fold Mellin-Barnes Integrals

    B. Ananthanarayan🇮🇳 · Sumit Banik🇮🇳 · Samuel Friot🇫🇷 · Shayan Ghosh🇩🇪

    Mellin-Barnes (MB) integrals are well-known objects appearing in many branches of mathematics and physics, ranging from hypergeometric functions theory to quantum field theory, solid state physics, asymptotic theory, etc. Although MB integrals have been studied for more than one century, until now there is no systematic computational technique of the multiple series representations of $N$-fold MB integrals for $N>2$. Relying on a simple geometrical analysis based on conic hulls, we show here a solution to this important problem. Our method can be applied to resonant (i.e logarithmic) and nonresonant cases and, depending on the form of the MB integrand, it gives rise to convergent series representations or diverging asymptotic ones. When convergent series are obtained the method also allows, in general, the determination of a single master series for each series representation, which considerably simplifies convergence studies and/or numerical checks. We provide, along with this paper, a Mathematica implementation of our technique with examples of applications. Among them, we present the first evaluation of the hexagon and double box conformal Feynman integrals with unit propagator powers.

    ↳ hep-thhep-phmath-phmath.MPPRL(2021)·56 citations
21. 21*

    Neutron - mirror neutron mixing and neutron stars

    Zurab Berezhiani🇮🇹 · Riccardo Biondi🇮🇹 · Massimo Mannarelli🇮🇹 · Francesco Tonelli🇮🇹

    The oscillation of neutrons $n$ into mirror neutrons $n^{\prime }$, their mass degenerate partners from dark mirror sector, can have interesting implications for neutron stars: an ordinary neutron star could gradually transform into a mixed star consisting in part of mirror dark matter. Mixed stars can be detectable as twin partners of ordinary neutron stars: namely, there can exist compact stars with the same masses but having different radii. For a given equation of state (identical between the ordinary and mirror components), the mass and radius of a mixed star depend on the proportion between the ordinary and mirror components in its interior which in turn depends on its age. If $50\%-50\%$ proportion between two fractions can be reached asymptotically in time, then the maximum mass of such "maximally mixed stars" should be $\sqrt{2}$ times smaller than that of ordinary neutron star while the stars exceeding a critical mass value $M_{NS}^{\max }/\sqrt{2}$ should collapse in black holes after certain time. We evaluate the evolution time and discuss the implications of $n-n^{\prime }$ transition for the pulsar observations as well as for the gravitational waves from the neutron star mergers and associated electromagnetic signals.

    ↳ astro-ph.HEastro-ph.GAhep-phnucl-thEPJC(2021)·63 citations
22. 22*

    Quantizing the Eisenhart Lift

    Kieran Finn🇬🇧 · Sotirios Karamitsos🇮🇹 · Apostolos Pilaftsis🇬🇧

    The classical Eisenhart lift is a method by which the dynamics of a classical system subject to a potential can be recreated by means of a free system evolving in a higher-dimensional curved manifold, known as the lifted manifold. We extend the formulation of the Eisenhart lift to quantum systems, and show that the lifted manifold recreates not only the classical effects of the potential, but also its quantum mechanical effects. In particular, we find that the solutions of the Schrodinger equations of the lifted system reduce to those of the original system after projecting out the new degrees of freedom. In this context, we identify a conserved quantum number, which corresponds to the lifted momentum of the classical system. We further apply the Eisenhart lift to Quantum Field Theory (QFT). We show that a lifted field space manifold is able to recreate both the classical and quantum effects of a scalar field potential. We find that, in the case of QFT, the analogue of the lifted momentum is a quantum charge that is conserved not only in time, but also in space. The different possible values for this charge label an ensemble of Fock spaces that are all disjoint from one another. The relevance of these extended Fock spaces to the cosmological constant and gauge hierarchy problems is considered.

    ↳ hep-thhep-phquant-phPRD(2021)·9 citations
23. 23*

    Quantum Corrections to the Accretion onto a Schwarzschild Black Hole in the Background of Quintessence

    Kourosh Nozari🇮🇷 · Milad Hajebrahimi🇮🇷 · Sara Saghafi🇮🇷

    It is well known that quantum effects may lead to remove the intrinsic singularity point of back holes. Also, the quintessence scalar field is a candidate model for describing late-time acceleration expansion. Accordingly, Kazakov and Solodukhin considered the existence of back-reaction of the spacetime due to the quantum fluctuations of the background metric to deform Schwarzschild black hole, which led to change the intrinsic singularity of the black hole to a 2-sphere with a radius of the order of the Planck length. Also, Kiselev rewrote the Schwarzschild metric by taking into account the quintessence field in the background. In this study, we consider the quantum-corrected Schwarzschild black hole inspired by Kazakov-Solodukhin's work, and Schwarzschild black hole surrounded by quintessence deduced by Kiselev to study the mutual effects of quantum fluctuations and quintessence on the accretion onto the black hole. Consequently, the radial component of 4-velocity and the proper energy density of the accreting fluid have a finite value on the surface of its central 2-sphere due to the presence of quantum corrections. Also, by comparing the accretion parameters in different kinds of black holes, we infer that the presence of a point-like electric charge in the spacetime is somewhat similar to some quantum fluctuations in the background metric.

    ↳ gr-qchep-phEPJC(2020)·37 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.