We establish a fundamental connection between quantum criticality of a many-body system, such as Bose-Einstein condensates, and its capacity of information-storage and processing. For deriving the effective theory of modes in the vicinity of the quantum critical point, we develop a new method by mapping a Bose-Einstein condensate of $N$-particles onto a sigma model with a continuous global (pseudo)symmetry that mixes bosons of different momenta. The Bogolyubov modes of the condensate are mapped onto the Goldstone modes of the sigma model, which become gapless at the critical point. These gapless Goldstone modes are the quantum carriers of information and entropy. Analyzing their effective theory, we observe information-processing properties strikingly similar to the ones predicted by the black hole portrait. The energy cost per qubit of information-storage vanishes in the large-$N$ limit and the total information-storage capacity increases with $N$ either exponentially or as a power law. The longevity of information-storage also increases with $N$, whereas the scrambling time in the over-critical regime is controlled by the Lyapunov exponent and scales logarithmically with $N$. This connection reveals that the origin of black hole information storage lies in the quantum criticality of the graviton Bose-gas, and that much simpler systems that can be manufactured in table-top experiments can exhibit very similar information-processing dynamics.

The vertex structure of QCD fixed in the maximal Abelian gauge (MAG) and Curci-Ferrari gauge is analyzed at two loops at the fully symmetric point for the 3-point functions corresponding to the three momentum subtraction (MOM) renormalization schemes. Consequently, the three-loop renormalization group functions are determined for each of these three schemes in each gauge using properties of the renormalization group equation.

Information about the last stages of a binary neutron star inspiral and the final merger can be extracted from quasiequilibrium configurations and dynamical evolutions. In this article, we construct quasiequilibrium configurations for different spins, eccentricities, mass ratios, compactnesses, and equations of state. For this purpose we employ the sgrid code, which allows us to construct such data in previously inaccessible regions of the parameter space. In particular, we consider spinning neutron stars in isolation and in binary systems; we incorporate new methods to produce highly eccentric and eccentricity-reduced data; we present the possibility of computing data for significantly unequal-mass binaries with mass ratios $q\simeq 2$; and we create equal-mass binaries with individual compactness up to $\mathcal{C}\simeq 0.23$. As a proof of principle, we explore the dynamical evolution of three new configurations. First, we simulate a $q=2.06$ mass ratio which is the highest mass ratio for a binary neutron star evolved in numerical relativity to date. We find that mass transfer from the companion star sets in a few revolutions before merger and a rest mass of $\sim {10}^{-2}{M}_{\odot }$ is transferred between the two stars. This amount of mass accretion corresponds to $\sim {10}^{51}\mathrm{ergs}$ of accretion energy. This configuration also ejects a large amount of material during merger ($\sim 7.6\times 10^{-2}{M}_{\odot }$), imparting a substantial kick to the remnant neutron star. Second, we simulate the first merger of a precessing binary neutron star. We present the dominant modes of the gravitational waves for the precessing simulation, where a clear imprint of the precession is visible in the (2,1) mode. Finally, we quantify the effect of an eccentricity-reduction procedure on the gravitational waveform. The procedure improves the waveform quality and should be employed in future precision studies. However, one also needs to reduce other errors in the waveforms, notably truncation errors, in order for the improvement due to eccentricity reduction to be effective.

Perturbations of asymptotically anti-de-Sitter (AdS) spacetimes are often considered by imposing field vanishing boundary conditions (BCs) at the AdS boundary. Such BCs, of Dirichlet-type, imply a vanishing energy flux at the boundary, but the converse is, generically, not true. Regarding AdS as a gravitational box, we consider vanishing energy flux (VEF) BCs as a more fundamental physical requirement and we show that these BCs can lead to a new branch of modes. As a concrete example, we consider Maxwell perturbations on Kerr-AdS black holes in the Teukolsky formalism, but our formulation applies also for other spin fields. Imposing VEF BCs, we find a set of two Robin BCs, even for Schwarzschild-AdS black holes. The Robin BCs on the Teukolsky variables can be used to study quasinormal modes, superradiant instabilities and vector clouds. As a first application, we consider here the quasinormal modes of Schwarzschild-AdS black holes. We find that one of the Robin BCs yields the quasinormal spectrum reported in the literature, while the other one unveils a new branch for the quasinormal spectrum.

The Tolman VII solution for a static perfect fluid sphere to the Einstein equations is reexamined, and a closed form class of equations of state (EOSs) is deduced for the first time. These EOSs allow further analysis to be carried out, leading to a viable model for compact stars with arbitrary boundary mass density to be obtained. Explicit application of causality conditions places further constraints on the model, and recent observations of masses and radii of neutron stars prove to be within the predictions of the model. The adiabatic index predicted is $\gamma \ge 2$, but self-bound crust solutions are not excluded if we allow for higher polytropic indices in the crustal regions of the star. The solution is also shown to obey known stability criteria often used in modeling such stars. It is argued that this solution provides realistic limits on models of compact stars, maybe even independently of the type of EOS, since most of the EOSs usually considered do show a quadratic density falloff to first order, and this solution is the unique exact solution that has this property.

By extending our recent framework to describe the tidal deformations of a spinning compact object, we compute for the first time the tidal Love numbers of a spinning neutron star to linear order in the angular momentum. The spin of the object introduces couplings between electric and magnetic distortions, and new classes of spin-induced (“rotational”) tidal Love numbers emerge. We focus on stationary tidal fields, which induce axisymmetric perturbations. We present the perturbation equations for both electric-led and magnetic-led rotational Love numbers for generic multipoles and explicitly solve them for various tabulated equations of state and for a tidal field with an electric (even parity) and magnetic (odd parity) component with $\ell =2$, 3, 4. For a binary system close to the merger, various components of the tidal field become relevant. In this case we find that an octupolar magnetic tidal field can significantly modify the mass quadrupole moment of a neutron star. Preliminary estimates, assuming a spin parameter $\chi \approx 0.05$, show modifications $\gtrsim 10\%$ relative to the static case, at an orbital distance of five stellar radii. Furthermore, the rotational Love numbers as functions of the moment of inertia are much more sensitive to the equation of state than in the static case, where approximate universal relations at the percent level exist. For a neutron-star binary approaching the merger, we estimate that the approximate universality of the induced mass quadrupole moment deteriorates from 1% in the static case to roughly 6% when $\chi \approx 0.05$. Our results suggest that spin-tidal couplings can introduce important corrections to the gravitational waveforms of spinning neutron-star binaries approaching the merger.

We first observe that for Lifshitz black holes of which the only charge is the mass, the resulting Smarr relation is a direct consequence of the Lifshitz Cardy formula. From this observation, we propose to extend the Cardy formula to the case of electrically charged Lifshitz black holes satisfying as well a Smarr relation. The expression of our formula depends on the dynamical exponent, the energy and the charge of the ground state which is played by a magnetically charged soliton obtained through a double Wick rotation. The expression also involves a factor multiplying the chemical potentials which varies in function of the electromagnetic theory considered. This factor is precisely the one that appears in the Smarr formula for charged Lifshitz black holes. We test the validity of this Cardy formula in different situations where electrically Lifshitz charged black holes satisfying a Smarr relation are known. We then extend these results to electrically charged black holes with hyperscaling violation. Finally, an example in the charged anti-de Sitter case is also provided.

In this short paper, we investigate the existence of universal relations between the gravimagnetic Love number of irrotational stars and the dimensionless moment of inertia. These Love numbers take into account the internal motion of the fluid, while the star is globally irrotational. The goal is to extend the so-called I-Love-Q relations—providing a strong correlation between the gravitoelectric Love number, the dimensionless moment of inertia and the dimensionless rotation-induced quadrupole—to the gravitomagnetic sector, where internal motion is taken into account. As a byproduct, we present for the first time this new gravitomagnetic Love number for realistic equations of state.

A nonminimal coupling between the dark matter and dark energy components may offer a way of solving the so-called coincidence problem. In this paper we propose a low-$z$ test for such hypothesis using measurements of the gas mass fraction $f_{\mathrm{gas}}$ in relaxed and massive galaxy clusters. The test applies to any model whose dilution of dark matter is modified with respect to the standard $a^{-3}$ scaling, as usual in interacting models, where $a$ is the cosmological scale factor. We apply the test to current $f_{\mathrm{gas}}$ data and perform Monte Carlo simulations to forecast the necessary improvements in number and accuracy of upcoming observations to detect a possible interaction in the cosmological dark sector. Our results show that improvements in the present relative error ${\sigma }_{\mathrm{gas}}/f_{\mathrm{gas}}$ are more effective to achieve this goal than an increase in the size of the $f_{\mathrm{gas}}$ sample.

We consider cosmological tests of a scalar-vector-tensor gravitational model, in which the dark energy is included in the total action through a gauge-invariant, electromagnetic type contribution. The ground state of dark energy, corresponding to a constant potential $V$, is a Bose-Einstein type condensate with spontaneously broken U(1) symmetry. In other words, dark energy appears as a massive vector field emerging from a superposition of a massless vector and a scalar field, the latter corresponding to the Goldstone boson. Two particular cosmological models, corresponding to pure electric and pure magnetic type potentials, respectively, are confronted with type IA supernovae and Hubble parameter data. In the electric case, a good fit is obtained along a narrow inclined stripe in the ${\mathrm{\Omega }}_m-{\mathrm{\Omega }}_V$ parameter plane, which includes the $\mathrm{\Lambda }$ cold dark matter limit as the best fit. The other points on this admissible region represent superconducting dark energy as a sum of a cosmological constant and a time-evolving contribution. In the magnetic case the cosmological test selects either (i) parameter ranges of the superconducting dark energy allowing for the standard baryonic sector plus dark matter or (ii) a unified superconducting dark matter and dark energy model, additionally including only the baryonic sector.

We present a two-stage hybrid inflationary scenario in nonminimal supergravity which can predict values of the tensor-to-scalar ratio of the order of a $\mathrm{few}\times {10}^{-2}$. For the parameters considered, the underlying supersymmetric particle physics model possesses two inflationary paths, the trivial and the semishifted one. The trivial path is stabilized by supergravity corrections and supports a first stage of inflation with a limited number of e-foldings. The tensor-to-scalar ratio can become appreciable while the value of the scalar spectral index remains acceptable as a result of the competition between the relatively mild supergravity corrections and the strong radiative corrections to the inflationary potential. The additional number of e-foldings required for solving the puzzles of hot big bang cosmology are generated by a second stage of inflation taking place along the semishifted path. This is possible only because the semishifted path is almost perpendicular to the trivial one, and thus not affected by the strong radiative corrections along the trivial path, and also because the supergravity effects remain mild. The requirement that the running of the scalar spectral index remain acceptable limits the possible values of the tensor-to-scalar ratio not to exceed about $5\times {10}^{-2}$. Our model predicts the formation of an unstable string-monopole network, which may lead to detectable gravity wave signatures in future space-based laser interferometer observations.

We derive for the first time the growth index of matter perturbations of the Friedmann-Lemaître-Robertson-Walker (FLRW) flat cosmological models in which the vacuum energy depends on redshift. A particularly well-motivated model of this type is the so-called quantum field vacuum, in which, apart from a leading constant term ${\mathrm{\Lambda }}_0$, there is also an $H^2$ dependence in the functional form of the vacuum, namely, $\mathrm{\Lambda }(H)={\mathrm{\Lambda }}_0+3\nu (H^2-H_0^2)$. Since $|\nu |\ll 1$, this form endows the vacuum energy of a mild dynamics which affects the evolution of the main cosmological observables at the background and perturbation levels. Specifically, at the perturbation level, we find that the growth index of the running vacuum cosmological model is ${\gamma }_{{\mathrm{\Lambda }}_H}\approx \frac{6+3\nu }{11-12\nu }$, and thus it nicely extends analytically the result of the $\mathrm{\Lambda }\mathrm{CDM}$ model, ${\gamma }_{\mathrm{\Lambda }}\approx 6/11$.

The sharp change in slope of the ultrahigh energy cosmic ray (UHECR) spectrum around $10^{18.6}\mathrm{eV}$ (the ankle), combined with evidence of a light but extragalactic component near and below the ankle and intermediate composition above, has proved exceedingly challenging to understand theoretically, without fine-tuning. We propose a mechanism whereby photo-disintegration of ultrahigh energy nuclei in the region surrounding a UHECR accelerator accounts for the observed spectrum and inferred composition at Earth. For suitable source conditions, the model reproduces the spectrum and the composition over the entire extragalactic cosmic ray energy range, i.e. above $10^{17.5}\mathrm{eV}$. Predictions for the spectrum and flavors of neutrinos resulting from this process are also presented.

The model-independent parametrization for exclusive hadronic form factors commonly used for semileptonic decays is generalized to allow for the inclusion of above-threshold resonant poles of known mass and width. We discuss the interpretation of such poles, particularly with respect to the analytic structure of the relevant two-point Green’s function in which they reside. Their presence has a remarkably small effect on the parametrization, as we show explicitly for the case of $D\to \pi e^{+}{\nu }_e$.

We analyze a simple extension of the standard model where the dark matter particle is a Dirac fermion that is a mixture of a singlet and an $SU(2)$ doublet. The model contains only four free parameters: the singlet and the doublet masses and two new Yukawa couplings. Direct detection bounds in this model are very strong and require the dark matter particle to be singletlike. As a result, its relic density has to be obtained via coannihilations with the doublet. We find that the dark matter mass should be below 750 GeV, the singlet-doublet mass difference cannot exceed 9%, and direct detection experiments offer the best chance to probe this scenario. Finally, we also show that this model can effectively arise in well-motivated extensions of the standard model.

We extend the Zee model, where tiny neutrino masses are generated at the one-loop level, to a supersymmetric model with $R$-parity conservation. It is found that the neutrino mass matrix can be consistent with the neutrino oscillation data thanks to the nonholomorphic Yukawa interaction generated via one-loop diagrams of sleptons. We find a parameter set of the model, where in addition to the neutrino oscillation data, experimental constraints from the lepton flavor violating decays of charged leptons and current LHC data are also satisfied. In the parameter set, an additional $CP$-even neutral Higgs boson other than the standard-model-like one, a $CP$-odd neutral Higgs boson, and two charged scalar bosons are light enough to be produced at the LHC and future lepton colliders. If the lightest charged scalar bosons are mainly composed of the $\mathrm{SU}(2{)}_L$-singlet scalar boson in the model, they would decay into $e\nu$ and $\mu \nu$ with 50% of a branching ratio for each. In such a case, the relation among the masses of the charged scalar bosons and the $CP$-odd Higgs in the minimal supersymmetric standard model approximately holds with a radiative correction. Our model can be tested by measuring the specific decay patterns of charged scalar bosons and the discriminative mass spectrum of additional scalar bosons.

We determine the next-to-leading order chiral low-energy constant $L_{10}^r$, and combinations $C_{12}^r\pm C_{61}^r+C_{80}^r$, $C_{13}^r-C_{62}^r+C_{81}^r$, $C_{61}^r$, and $C_{87}^r$, of the next-to-next-to-leading order (NNLO) chiral low-energy constants incorporating recently revised ALEPH results for the nonstrange vector ($V$) and axial-vector ($A$) hadronic $\tau$ decay distributions and recently updated RBC/UKQCD lattice data for the nonstrange $V-A$ two-point function. In the $\overline{\mathrm{MS}}$ scheme, at renormalization scale $\mu =770\mathrm{MeV}$, we find $L_{10}^r=-0.00350(17)$, $C_{12}^r+C_{61}^r+C_{80}^r=0.00237(16){\mathrm{GeV}}^{-2}$, $C_{12}^r-C_{61}^r+C_{80}^r=-0.00056(15){\mathrm{GeV}}^{-2}$, $C_{13}^r-C_{62}^r+C_{81}^r=0.00046(9){\mathrm{GeV}}^{-2}$, $C_{61}^r=0.00146(15){\mathrm{GeV}}^{-2}$, and $C_{87}^r=0.00510(22){\mathrm{GeV}}^{-2}$. With errors here at or below the level expected for contributions of yet higher order in the chiral expansion, the analysis exhausts the possibilities of what can be meaningfully achieved in an NNLO analysis. We also consider the dimension-six and dimension-eight coefficients in the operator product expansion in the $V-A$ channel.

Within the model-independent framework of $SU(3)\times SU(2)\times U(1)$ gauge-invariant dimension-six operators, we study flavor off-diagonal $Wtq$ couplings ($q=d$, $s$) and related four-quark contact interactions involving the top. We obtain bounds on those couplings from Tevatron and LHC data for single-top production and branching fractions in top decays, as well as other experimental results on flavor-changing neutral-current processes including $B\to X_q\gamma$ and $Z\to b\overline{q}$ decays ($q=d$, $s$). We also update the bounds on flavor-diagonal $Wtb$ couplings using the most recent measurement of $W$-helicity fractions in top decays from top-pair production.