We have studied the masse spectra for the $cc\overline{b}\overline{b}$ and $bb\overline{c}\overline{c}$ tetraquark states with quantum numbers $J^P=0^{\pm },1^{\pm }$, and $2^{+}$. We systematically construct the interpolating currents with various spin-parity quantum numbers and calculate their two-point correlation functions in the framework of QCD moment sum rule method. Our calculations show that the masses are about 12.3–12.4 GeV for the positive parity $cc\overline{b}\overline{b}$ tetraquark ground states with $J^P=0^{+},1^{+},2^{+}$, while 12.8–13.1 GeV for the negative parity channels with $J^P=0^{-},1^{-}$. The mass predictions for the positive parity $cc\overline{b}\overline{b}$ ground states are lower than the $B_c{B}_c$ threshold, implying that these tetraquarks can only decay via weak interaction and thus are expected to be stable and narrow.

Two distant black holes can be connected in the interior through a wormhole. Such a wormhole has been interpreted as an entangled state shared between two exterior regions. If Alice and Bob send signals into each of the black holes, then they can meet in the interior. In this paper, we interpret this meeting in terms of the quantum circuit that prepares the entangled state: Alice and Bob sending signals creates growing perturbations in the circuit, whose overlap represents their meeting inside the wormhole. We argue that such overlap in the circuit is quantified by a particular six-point correlation function. Therefore, exterior observers in possession of the entangled qubits can use this correlation function to diagnose the collision in the interior without having to jump in themselves.

We show that the gravitational waves generated by the perturbations of general relativistic black holes can be considered as a direct probe of the existence of dark sector interactions. Working within the framework of Horndeski theory and linear perturbations, we show that dark sector interactions effectively reduce to an interaction charge that influences both scalar and tensor waveforms. Furthermore, we show that the total dark matter field, including the effects of dark sector interactions, satisfies a conservation equation embodying the equivalence principle. We exploit this realization to setup the Regge-Wheeler equation and the coupled Zerilli and scalar wave equations for a Schwarzschild-(anti) de Sitter black hole. We then present numerical integration of the coupled even-parity wave equations for the case of a dark matter particle falling straight down into a Schwarzschild black hole.

We revisit several aspects of the interaction of self-gravitating, slowly varying sources with their own emitted radiation within the context of post-Newtonian approximation to General Relativity. We discuss and clarify the choice of boundary conditions of the Green’s functions used to determine conservative potentials and the interplay between the so-called near and far zones as well as the relation between far-zone ultraviolet divergences and emitted power. Both near- and far-zone contributions are required for the computation of the conservative dynamics. Within a field-theory approach, we rederive far-zone self-energy processes, known as tail and memory effects, generalizing the calculation of their divergent part to arbitrary order in the post-Newtonian expansion and at second order in the Newton constant.

In all inflationary scenarios of primordial black hole (PBH) formation, amplified scalar perturbations inevitably accompany an induced stochastic gravitational wave background (ISGWB) at smaller scales. In this paper, we study the ISGWB originating from the inflationary model, introduced in our previous paper [N. Bhaumik and R. K. Jain, Primordial black holes dark matter from inflection point models of inflation and the effects of reheating, J. Cosmol. Astropart. Phys. 01 (2020) 037] wherein PBHs can be produced with a nearly monochromatic mass fraction in the asteroid mass window accounting for the total dark matter in the universe. We numerically calculate the ISGWB in our scenario for frequencies ranging from nano-Hz to kHz that covers the observational scales corresponding to future space-based gravitational wave (GW) observatories such as IPTA, LISA, DECIGO, and Einstein Telescope. Interestingly, we find that ultralight PBHs ($M_{\mathrm{PBH}}\sim {10}^{-20}{M}_{\odot }$), which shall completely evaporate by today with an exceedingly small contribution to dark matter, would still generate an ISGWB that may be detected by a future design of the ground-based Advanced LIGO detector. Using a model-independent approach, we obtain a stringent lower mass limit for ultralight PBHs which would be valid for a large class of ultra slow roll inflationary models. Further, we extend our formalism to study the imprints of a reheating epoch on both the ISGWB and the derived lower mass bound. We find that any noninstantaneous reheating leads to an even stronger lower bound on the PBH mass and an epoch of a prolonged matter-dominated reheating shifts the ISGWB spectrum to smaller frequencies. In particular, we show that an epoch of an early matter-dominated phase leads to a secondary amplification of the ISGWB at a much smaller scale corresponding to the smallest comoving scale leaving the horizon during inflation or the end of the inflation scale. Finally, we discuss the prospects of the ISGWB detection by the proposed and upcoming GW observatories.

We propose an inflationary scenario based on the concurrent presence of nonminimal coupling (NMC) and generalized nonminimal derivative coupling (GNMDC), in the context of Higgs inflation. The combined construction maintains the advantages of the individual scenarios without sharing their disadvantages. In particular, a long inflationary phase can be easily achieved due to the gravitational friction effect owed to the GNMDC, without leading to trans-Planckian values and unitarity violation. Additionally, the tensor-to-scalar ratio remains at low values due to the NMC contribution. Finally, the instabilities related to the squared sound speed of scalar perturbations, which plague the simple GNMDC scenarios, are now healed due to the domination of the NMC contribution and the damping of the GNMDC effects during the reheating era. These features make scenarios with nonminimal and derivative couplings to gravity successful candidates for the description of inflation.

We study the cosmological signatures of having extra energy density, ${\rho }_{ex}$, beyond the $\mathrm{\Lambda }\mathrm{CDM}$ model that dilutes rapidly, faster than radiation, at a scale factor $a_c$ with a corresponding mode $k_c=a_{c}H(a_c)$ crossing the horizon at that time. These types of models are motivated by phase transitions of the underlying elementary particles, for example, the creation of protons and neutrons from almost massless quarks or the recently proposed bound dark energy model. The rapid dilution of ${\rho }_{ex}$ leaves distinctive imprints in the Universe not only in the expansion history with a clear impact on the acoustic scale, $r_s(a_{c}c)$, and angular distances, $D_A(a)$, but also in the matter and cosmic microwave background power spectra. The rapidly diluted energy density ${\rho }_{ex}$ generates characteristic signatures that can be observed with current and future precision cosmological data. In particular, we find a bump in the matter power spectrum compared to the standard $\mathrm{\Lambda }\mathrm{CDM}$. We identify the amplitude, width, and timescale of the bump to the physical properties of the transition. We study these effects with linear theory, standard perturbation theory, and the correlated impact on cosmological distances, allowing for independent measurements of these extensions of the standard $\mathrm{\Lambda }\mathrm{CDM}$ model. To generate the bumps, we use different models that work at early times well inside the radiation domination epoch, during matter domination, or at late times when dark energy is the main component.

We consider the indirect detection of dark matter that is captured in the Sun and subsequently annihilates to long-lived dark mediators. If these mediators escape the Sun before decaying, they can produce striking gamma ray signals, either via the decay of the mediators directly to photons or via bremsstrahlung and hadronization of the mediator decay products. Using recent measurements from the HAWC Observatory, we determine model-independent limits on heavy dark matter that are orders of magnitude more powerful than direct detection experiments, for both spin-dependent and spin-independent scattering. We also consider a well-motivated model in which fermionic dark matter annihilates to dark photons. For such a realistic scenario, the strength of the solar gamma ray constraints are reduced, compared to the idealistic case, because the dark matter capture cross section and mediator lifetime are related. Nonetheless, solar gamma ray constraints enable us to exclude a previously unconstrained region of dark photon parameter space.

We obtain new estimates for the parameters ${\lambda }_E^2$, ${\lambda }_H^2$ and their ratio $\mathcal{R}={\lambda }_E^2/{\lambda }_H^2$, which appear in the second moments of the $B$-meson light-cone distribution amplitudes defined in the heavy-quark effective field theory. The computation is based on two-point QCD sum rules for the diagonal correlation function and includes all contributions up to mass dimension seven in the operator-product expansion. For the ratio we get $\mathcal{R}=(0.1\pm 0.1)$ with ${\lambda }_H^2=(0.15\pm 0.05){\mathrm{GeV}}^2$ and ${\lambda }_E^2=(0.01\pm 0.01){\mathrm{GeV}}^2$.

We consider relatively heavy neutrinos ${\nu }_H$, mostly contributing to a sterile state ${\nu }_s$, with mass in the range $10\mathrm{MeV}\lesssim m_s\lesssim m_{\pi }\sim 135\mathrm{MeV}$, which are thermally produced in the early Universe in collisional processes involving active neutrinos and freezing out after the QCD phase transition. If these neutrinos decay after the active neutrino decoupling, they generate extra neutrino radiation but also contribute to entropy production. Thus, they alter the value of the effective number of neutrino species $N_{\mathrm{eff}}$ as, for instance, measured by the cosmic microwave background (CMB), as well as affect primordial nucleosynthesis (BBN), notably ${}^4\mathrm{He}$ production. We provide a detailed account of the solution of the relevant Boltzmann equations. We also identify the parameter space allowed by current Planck satellite data and forecast the parameter space probed by future stage-4 ground-based CMB observations, expected to match or surpass BBN sensitivity.

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 $V$ ($V=\rho$, $K^{*}$) agree with those derived in QCD sum rules. The shape parameter for the $B_s$ meson distribution amplitude and the weak phase ${\varphi }_3(\gamma )=(75.2\pm 2.9)°$ consistent with the value in Particle Data Group are also obtained. It is straightforward to extend our analysis to higher orders and higher powers, when the corresponding subleading contributions are available in the PQCD approach, and to the global determination of LCDAs for other hadrons.

The Zee model for Dirac neutrinos is one of the simplest models featuring one-loop Dirac neutrino masses. The interactions between the new scalars (two singly charged fields) and neutrinos induce general neutrino interactions (GNI) which, as a generalization of the nonstandard neutrino interactions, constitute an additional tool to probe models beyond the Standard Model like this. In this work, we consider a $U(1{)}_{B-L}$ gauge symmetry as being responsible for the Diracness of the neutrinos and the radiative character of the neutrino masses. We determine the viable parameter space consistent with neutrino oscillation data, leptonic rare decays, and collider constraints, and establish the most relevant experimental prospects regarding lepton flavor violation searches and GNI in future solar neutrino experiments.

A number of direct detection experiments are searching for electron excitations created by the scattering of sub-GeV dark matter. We present an alternate formulation of dark matter-electron scattering in terms of the dielectric response of a material. For dark matter which couples to electrons, this approach automatically accounts for in-medium screening effects, which were not included in previous rate calculations for semiconductor targets. We show that the screening effects appear for both scalar and vector mediators. The result is a non-negligible reduction of reach for direct detection experiments which use dielectric materials as targets. We also explore different determinations of the dielectric response, including first-principles density functional theory (DFT) calculations and a data-driven analytic approximation using a Mermin oscillator model.

Recently, the MiniBooNE experiment at Fermilab has updated the results with increased data and reported an excess of $560.6\pm 119.6$ electronlike events ($4.7\sigma$) in the neutrino operation mode. In this paper, we propose a scenario to account for the excess where a Dirac-type sterile neutrino, produced by a charged kaon decay through the neutrino mixing, decays into a leptophilic axionlike particle ($\ell \mathrm{ALP}$) and a muon neutrino. The electron-positron pairs produced from the $\ell \mathrm{ALP}$ decays can be interpreted as electronlike events provided that their opening angle is sufficiently small. In our framework, we consider the $\ell \mathrm{ALP}$ with a mass $m_a=20\mathrm{MeV}$ and an inverse decay constant $c_e/f_a={10}^{-2}{\mathrm{GeV}}^{-1}$, allowed by the astrophysical and experimental constraints. Then, after integrating the predicted angular or visible energy spectra of the $\ell \mathrm{ALP}$ to obtain the total excess event number, we find that our scenario with sterile neutrino masses within $150\mathrm{MeV}\lesssim m_N\lesssim 380\mathrm{MeV}$ ($150\mathrm{MeV}\lesssim m_N\lesssim 180\mathrm{MeV}$) and neutrino mixing parameters between ${10}^{-10}\lesssim |U_{\mu 4}{|}^2\lesssim {10}^{-8}$ ($3\times {10}^{-7}\lesssim |U_{\mu 4}{|}^2\lesssim 8\times {10}^{-7}$) can explain the MiniBooNE data.

In this work, we consider the question of local Hilbert space factorization in 2D conformal field theory. Generalizing previous work on entanglement and open-closed TQFT, we interpret the factorization of CFT states in terms of path integral processes that split and join the Hilbert spaces of circles and intervals. More abstractly, these processes are cobordisms of an extended CFT which are defined purely in terms of the OPE data. In addition to the usual sewing axioms, we impose an entanglement boundary condition that is satisfied by the vacuum Ishibashi state. This choice of entanglement boundary state leads to reduced density matrices that sum over super-selection sectors, which we identify as the CFT edge modes. Finally, we relate our factorization map to the coproduct formula for the CFT symmetry algebra, which we show is equivalent to a Boguliubov transformation in the case of a free boson.

We show that $CP$-violating Weyl anomaly induces a supersymmetry anomaly in the formulation of superconformal supergravity as is observed in $CP$-preserving cases. This supersymmetry anomaly can be removed in the old minimal supergravity by adding suitable local counterterms, and it becomes a consistent theory.

We study thermodynamics and critical behaviors of higher-dimensional Lovelock black holes with nonmaximally symmetric horizons in the canonical ensemble of extended phase space. The effects from nonconstancy of the horizon of the black hole via appearing two chargelike parameters in thermodynamic quantities of third-order Lovelock black hole are investigated. We find that Ricci flat black holes with nonconstant curvature horizon show critical behavior. This is an interesting feature that is not seen for any kind of black hole in Einstein or Lovelock gravity in the literature. We examine how various interesting thermodynamic phenomena such as standard first-order small-large black hole phase transition, a reentrant phase transition, or zeroth order phase transition happen for Ricci flat, spherical, or hyperbolic black holes with nonconstant curvature horizon depending on the values of Lovelock coefficient and chargelike parameters. While for a spherical black hole of third order Lovelock gravity with constant curvature horizon phase transition is observed only for $7\le d\le 11$, for our solution criticality and phase transition exist in every dimension. With a proper choice of the free parameters, a large-small-large black hole phase transition occurs. This process is accompanied by a finite jump of the Gibbs free energy referred to as a zeroth-order phase transition. For the case $\kappa =-1$ a novel behavior is found for which three critical points could exist.

We provide a systematic analysis of the multipolar gravitational waveform, energy, and angular momentum fluxes emitted by a nonspinning test particle orbiting a Kerr black hole along equatorial, eccentric orbits. These quantities are computed by solving numerically the Teukolsky equation in the time domain using teukode and are then used to establish the reliability of a recently introduced prescription to deal with eccentricity-driven effects in the radiation reaction (and waveform) of the effective-one-body (EOB) model. The prescription relies on the idea of incorporating these effects by replacing the quasicircular Newtonian (or leading-order) prefactors in the EOB-factorized multipolar waveform (and fluxes) with their generic counterparts. To reliably account for strong-field regimes, standard factorization and resummation procedures had to be implemented also for the circular sector of $\ell =7$ and $\ell =8$ waveform multipoles. The comparison between numerical and analytical quantities is carried out over a large portion of the parameter space, notably for orbits close to the separatrix and with high eccentricities. The analytical fluxes agree to $\sim 2\%$ with the numerical data for orbits with moderate eccentricities ($e\lesssim 0.3$) and moderate spins ($\widehat{a}\lesssim 0.5$), although this increases up to $\sim 33\%$ for large, positive, black hole spins ($\sim 0.9$) and large eccentricities ($\sim 0.9$). Similar agreement is also found for the waveform. For moderate eccentricities, the EOB fluxes can be used to drive the test-particle dynamics through the nonadiabatic transition from eccentric inspiral to plunge, merger, and ringdown. Over this dynamics, we construct a complete EOB waveform, including merger and ringdown, that shows an excellent phasing and amplitude agreement with the numerical one. We also show that the same technique can be applied to hyperbolic encounters. In general, our approach to radiation reaction for eccentric inspirals should be seen as a first step toward EOB modelization of extreme-mass-ratio-inspirals waveforms for LISA.

It is shown that the equalization of temperatures between our and mirror sectors occurs during one Hubble time due to microscopic black hole production and evaporation in particle collisions if the temperature of the Universe is near the multidimensional Plank mass. This effect excludes multidimensional Planck masses smaller than the reheating temperature of the Universe ($\sim {10}^{13}\mathrm{GeV}$) in the mirror matter models, because the primordial nucleosynthesis theory requires that the temperature of the mirror world should be lower than ours. In particular, the birth of microscopic black holes in the LHC is impossible if the dark matter of our Universe is represented by baryons of mirror matter. It excludes some of the possible coexisting options in particle physics and cosmology. Multidimensional models with flat additional dimensions are already strongly constrained in maximum temperature due to the effect of Kaluza-Klein mode (KK-mode) overproduction. In these models, the reheating temperature should be significantly less than the multidimensional Planck mass, so our restrictions in this case are not paramount. The new constraints play a role in multidimensional models in which the spectrum of KK modes does not lead to their overproduction in the early Universe, for example, in theories with hyperbolic additional space.