The 100 most-cited articles in Physical review. D/Physical review. D., 2021

We present the cosmological implications from final measurements of clustering using galaxies, quasars, and $\mathrm{Ly}\ensuremath{\alpha}$ forests from the completed Sloan Digital Sky Survey (SDSS) lineage of experiments in large-scale structure. These experiments, composed of data from SDSS, SDSS-II, BOSS, and eBOSS, offer independent measurements of baryon acoustic oscillation (BAO) measurements of angular-diameter distances and Hubble distances relative to the sound horizon, ${r}_{d}$, from eight different samples and six measurements of the growth rate parameter, $f{\ensuremath{\sigma}}_{8}$, from redshift-space distortions (RSD). This composite sample is the most constraining of its kind and allows us to perform a comprehensive assessment of the cosmological model after two decades of dedicated spectroscopic observation. We show that the BAO data alone are able to rule out dark-energy-free models at more than eight standard deviations in an extension to the flat, $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ model that allows for curvature. When combined with Planck Cosmic…

Gravitational waves enable tests of general relativity in the highly dynamical and strong-field regime. Using events detected by LIGO-Virgo up to 1 October 2019, we evaluate the consistency of the data with predictions from the theory. We first establish that residuals from the best-fit waveform are consistent with detector noise, and that the low- and high-frequency parts of the signals are in agreement. We then consider parametrized modifications to the waveform by varying post-Newtonian and phenomenological coefficients, improving past constraints by factors of $\ensuremath{\sim}2$; we also find consistency with Kerr black holes when we specifically target signatures of the spin-induced quadrupole moment. Looking for gravitational-wave dispersion, we tighten constraints on Lorentz-violating coefficients by a factor of $\ensuremath{\sim}2.6$ and bound the mass of the graviton to ${m}_{g}\ensuremath{\le}1.76\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}23}\text{ }\text{ }\mathrm{eV}/{c}^{2}$ with 90% credibility. We also analyze the properties of the merger remnants by…

This work details the release of the CTEQ-TEA collaboration's updated set of parton distribution functions, CT18. These PDFs are a crucial input to almost all theory and experimental calculations carried out at the LHC and potentially other hadron colliders. The new set supersedes the CT14 analysis, incorporating additional data from the HERA and LHC experiments and providing alternative fits to explore the effect of different input assumptions.

We present imrphenomxphm, a phenomenological frequency-domain model for the gravitational-wave signal emitted by quasicircular precessing binary black holes, which incorporates multipoles beyond the dominant quadrupole in the precessing frame. The model is a precessing extension of imrphenomxhm, [C. Garc\'{\i}a-Quir\'os et al., Phys. Rev. D 102, 064002 (2020)] based on approximate maps between aligned-spin waveform modes in the coprecessing frame and precessing waveform modes in the inertial frame, which is commonly referred to as ``twisting up'' the nonprecessing waveforms. imrphenomxphm includes imrphenomxp as a special case, the restriction to the dominant quadrupole contribution in the coprecessing frame. We implement two alternative mappings, one based on a single-spin post-Newtonian approximation, as used in imrphenompv2 [M. Hannam et al., Phys. Rev. Lett. 113, 151101 (2014).], and one based on the double-spin multiple scale analysis approach of [K. Chatziioannou et al., Phys. Rev. D 95, 104004 (2017).]. We include a detailed discussion of conventions used in the description…

We report results of a search for an isotropic gravitational-wave background (GWB) using data from Advanced LIGO's and Advanced Virgo's third observing run (O3) combined with upper limits from the earlier O1 and O2 runs. Unlike in previous observing runs in the advanced detector era, we include Virgo in the search for the GWB. The results of the search are consistent with uncorrelated noise, and therefore we place upper limits on the strength of the GWB. We find that the dimensionless energy density ${\mathrm{\ensuremath{\Omega}}}_{\mathrm{GW}}\ensuremath{\le}5.8\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}9}$ at the 95% credible level for a flat (frequency-independent) GWB, using a prior which is uniform in the log of the strength of the GWB, with 99% of the sensitivity coming from the band 20--76.6 Hz; ${\mathrm{\ensuremath{\Omega}}}_{\mathrm{GW}}(f)\ensuremath{\le}3.4\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}9}$ at 25 Hz for a power-law GWB with a spectral index of $2/3$ (consistent with expectations for compact binary coalescences), in the band 20--90.6 Hz;…

The curvature parameter tension between Planck 2018, cosmic microwave background (CMB) lensing, and baryon acoustic oscillation (BAO) data is measured using the suspiciousness statistic to be $2.5--3\ensuremath{\sigma}$. Conclusions regarding the spatial curvature of the Universe which stem from the combination of these data should therefore be viewed with suspicion. Without CMB lensing or BAO, Planck 2018 has a moderate preference for closed universes, with Bayesian betting odds of over $50\ensuremath{\mathbin:}1$ against a flat universe and over $2000\ensuremath{\mathbin:}1$ against an open universe.

The IceCube Neutrino Observatory has established the existence of a high-energy all-sky neutrino flux of astrophysical origin. This discovery was made using events interacting within a fiducial region of the detector surrounded by an active veto and with reconstructed energy above 60 TeV, commonly known as the high-energy starting event sample (HESE). We revisit the analysis of the HESE sample with an additional 4.5 years of data, newer glacial ice models, and improved systematics treatment. This paper describes the sample in detail, reports on the latest astrophysical neutrino flux measurements, and presents a source search for astrophysical neutrinos. We give the compatibility of these observations with specific isotropic flux models proposed in the literature as well as generic power-law-like scenarios. Assuming ${\ensuremath{\nu}}_{e}:{\ensuremath{\nu}}_{\ensuremath{\mu}}:{\ensuremath{\nu}}_{\ensuremath{\tau}}=1:1:1$, and an equal flux of neutrinos and antineutrinos, we find that the astrophysical neutrino spectrum is compatible with an unbroken power law, with a preferred…

Our understanding of strong gravity near supermassive compact objects has recently improved thanks to the measurements made by the Event Horizon Telescope (EHT). We use here the M87* shadow size to infer constraints on the physical charges of a large variety of nonrotating or rotating black holes. For example, we show that the quality of the measurements is already sufficient to rule out that M87* is a highly charged dilaton black hole. Similarly, when considering black holes with two physical and independent charges, we are able to exclude considerable regions of the space of parameters for the doubly-charged dilaton and the Sen black holes.

The present work studies one of Einstein's alternative formulations based on the nonmetricity scalar $Q$ generalized as $f(Q)$ theory. More specifically, we consider the power-law form of $f(Q)$ gravity, i.e., $f(Q)=Q+\ensuremath{\alpha}{Q}^{n}$. Here, we analyze the behavior of the cosmological model at the background and perturbation level. Using the dynamical system analysis, at the background level, we find the effective evolution of the model is the same as that of the $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ for $|n|<1$. Interestingly, the geometric component of the theory solely determined the late-time acceleration of the Universe. We also examine the integrability of the model by employing the method of singularity analysis. In particular, we find the conditions under which field equations pass the Painlev\'e test and hence possess the Painlev\'e property. While the equations pass the Painlev\'e test in the presence of dust for any value of $n$, the test is valid after the addition of radiation fluid only for $n<1$. Finally, at the perturbation level, the behavior of…

The dark photon is a massive hypothetical particle that interacts with the Standard Model by kinetically mixing with the visible photon. For small values of the mixing parameter, dark photons can evade cosmological bounds to be a viable dark matter candidate. Due to the similarities with the electromagnetic signals generated by axions, several bounds on dark photon signals are simply reinterpretations of historical bounds set by axion haloscopes. However, the dark photon has a property that the axion does not: an intrinsic polarization. Due to the rotation of the Earth, accurately accounting for this polarization is nontrivial, highly experiment dependent, and depends upon assumptions about the dark photon's production mechanism. We show that if one does account for the dark photon polarization, and the rotation of the Earth, an experiment's discovery reach can be enhanced by over an order of magnitude. We detail the strategies that would need to be taken to properly optimize a dark photon search. These include judiciously choosing the location and orientation of the experiment, as…

We present measurements of the $E$-mode ($EE$) polarization power spectrum and temperature-$E$-mode ($TE$) cross-power spectrum of the cosmic microwave background using data collected by SPT-3G, the latest instrument installed on the South Pole Telescope. This analysis uses observations of a $1500\text{ }\text{ }{\mathrm{deg}}^{2}$ region at 95, 150, and 220 GHz taken over a four-month period in 2018. We report binned values of the $EE$ and $TE$ power spectra over the angular multipole range $300\ensuremath{\le}\ensuremath{\ell}<3000$, using the multifrequency data to construct six semi-independent estimates of each power spectrum and their minimum-variance combination. These measurements improve upon the previous results of SPTpol across the multipole ranges $300\ensuremath{\le}\ensuremath{\ell}\ensuremath{\le}1400$ for $EE$ and $300\ensuremath{\le}\ensuremath{\ell}\ensuremath{\le}1700$ for $TE$, resulting in constraints on cosmological parameters comparable to those from other current leading ground-based experiments. We find that the SPT-3G data set is well fit by a…

In the current $3\ensuremath{\nu}$ paradigm, neutrino flavor oscillations probe three mixing angles $({\ensuremath{\theta}}_{12},{\ensuremath{\theta}}_{23},{\ensuremath{\theta}}_{13})$, one $CP$-violating phase $\ensuremath{\delta}$, and two independent differences between the squared masses ${m}_{i}^{2}$, that can be chosen as $\ensuremath{\delta}{m}^{2}={m}_{2}^{2}\ensuremath{-}{m}_{1}^{2}>0$ and $\mathrm{\ensuremath{\Delta}}{m}^{2}={m}_{3}^{2}\ensuremath{-}({m}_{1}^{2}+{m}_{2}^{2})/2$, where $\mathrm{sign}(\mathrm{\ensuremath{\Delta}}{m}^{2})=+(\ensuremath{-})$ for normal (inverted) mass ordering. Absolute $\ensuremath{\nu}$ masses can be probed by the effective mass ${m}_{\ensuremath{\beta}}$ in beta decay, by the total mass $\mathrm{\ensuremath{\Sigma}}$ in cosmology and---if neutrinos are Majorana---by another effective mass ${m}_{\ensuremath{\beta}\ensuremath{\beta}}$ in neutrinoless double beta decay. Within an updated global analysis of oscillation and nonoscillation data, we constrain these $3\ensuremath{\nu}$ parameters, both separately and in selected pairs, and…

Black hole superradiance is a powerful probe of light, weakly coupled hidden sector particles. Many candidate particles, such as axions, generically have self-interactions that can influence the evolution of the superradiant instability. As pointed out in [A. Gruzinov, arXiv:1604.06422.] in the context of a toy model, much of the existing literature on spin-0 superradiance does not take into account the most important self-interaction-induced processes. These processes lead to energy exchange between quasi-bound levels and particle emission to infinity; for large self-couplings, superradiant growth is saturated at a quasi-equilibrium configuration of reduced level occupation numbers. In this paper, we perform a detailed analysis of the rich dynamics of spin-0 superradiance with self-interactions, and the resulting observational signatures. We focus on quartic self-interactions, which dominate the evolution for most models of interest. We explore multiple distinct regimes of parameter space introduced by a nonzero self-interaction, including the simultaneous population of two or more…

We present a complete list of the dimension-eight operator basis in the standard model effective field theory using group theoretic techniques in a systematic and automated way. We adopt a new form of operators in terms of the irreducible representations of the Lorentz group and identify the Lorentz structures as states in a $SU(N)$ group. In this way, redundancy from equations of motion is absent and that from integration by part is treated using the fact that the independent Lorentz basis forms an invariant subspace of the $SU(N)$ group. We also decompose operators into the ones with definite permutation symmetries among flavor indices to deal with subtlety from repeated fields. For the first time to our knowledge, we provide the explicit form of independent flavor-specified operators in a systematic way. Our algorithm can easily be applied to higher-dimensional standard model effective field theory and other effective field theories, making these studies more approachable.

The authors discuss in detail a popular scenario to alleviate the current Hubble tension (different measurements of the expansion rate of the Universe show a 4.4 $\ensuremath{\sigma}$ discrepancy), namely ``early dark energy''. Hereby a false vacuum early on acts as an additional repulsive force (dark energy) but decays quickly enough to remain consistent with numerous other observational data. Contrary to the usual approach, a first order phase transition is considered, allowing in a minimal model a reduction of the tension to 2.5 $\ensuremath{\sigma}$.

Primordial black holes could have been formed in the early universe from nonlinear cosmological perturbations reentering the cosmological horizon when the Universe was still radiation dominated. Starting from the shape of the power spectrum on superhorizon scales, we provide a simple prescription, based on the results of numerical simulations, to compute the threshold ${\ensuremath{\delta}}_{c}$ for primordial black hole formation. Our procedure takes into account both the nonlinearities between the Gaussian curvature perturbation and the density contrast and, for the first time in the literature, the nonlinear effects arising at horizon crossing, which increase the value of the threshold by about a factor two with respect to the one computed on superhorizon scales.

We investigate the impact on cosmological observables of $f(Q)$-gravity, a specific class of modified gravity models in which gravity is described by the nonmetricity scalar, $Q$. In particular we focus on a specific model which is indistinguishable from the $\mathrm{\ensuremath{\Lambda}}$-cold-dark-matter ($\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$) model at the background level, while showing peculiar and measurable signatures at linear perturbation level. These are attributed to a time-dependent Planck mass and are regulated by a single dimensionless parameter, $\ensuremath{\alpha}$. In comparison to the $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ model, we find for positive values of $\ensuremath{\alpha}$ a suppressed matter power spectrum and lensing effect on the cosmic microwave background radiation (CMB) angular power spectrum and an enhanced integrated-Sachs-Wolfe tail of CMB temperature anisotropies. The opposite behaviors are present when the $\ensuremath{\alpha}$ parameter is negative. We also investigate the modified gravitational waves (GWs) propagation and show the…

The MiniBooNE experiment at Fermilab reports a total excess of $638.0\ifmmode\pm\else\textpm\fi{}52.1(\mathrm{stat}.)\ifmmode\pm\else\textpm\fi{}122.2(\mathrm{syst}.)$ electronlike events from a data sample corresponding to $18.75\ifmmode\times\else\texttimes\fi{}{10}^{20}$ protons-on-target in neutrino mode, which is a 46% increase in the data sample with respect to previously published results and $11.27\ifmmode\times\else\texttimes\fi{}{10}^{20}$ protons-on-target in antineutrino mode. The overall significance of the excess, $4.8\ensuremath{\sigma}$, is limited by systematic uncertainties, assumed to be Gaussian, as the statistical significance of the excess is $12.2\ensuremath{\sigma}$. The additional statistics allow several studies to address questions on the source of the excess. First, we provide two-dimensional plots in visible energy and the cosine of the angle of the outgoing lepton, which can provide valuable input to models for the event excess. Second, we test whether the excess may arise from photons that enter the detector from external events or photons exiting the…

We present the fastemriwaveforms (FEW) package, a collection of tools to build and analyze extreme mass ratio inspiral (EMRI) waveforms. Here, we expand on [A. J. K. Chua et al., Phys. Rev. Lett. 126, 051102 (2021).] that introduced the first fast and accurate fully-relativistic EMRI waveform template model. We discuss the construction of the overall framework; constituent modules; and the general methods used to accelerate EMRI waveforms. Because the fully relativistic FEW model waveforms are for now limited to eccentric orbits in the Schwarzschild spacetime, we also introduce an improved augmented analytic kludge (AAK) model that describes generic Kerr inspirals. Both waveform models can be accelerated using graphics processing unit (GPU) hardware. With the GPU-accelerated waveforms in hand, a variety of studies are performed including an analysis of EMRI mode content, template mismatch, and fully Bayesian Markov Chain Monte Carlo-based EMRI parameter estimation. We find relativistic EMRI waveform templates can be generated with fewer harmonic modes ($\ensuremath{\sim}10--100$)…

X-ray pulse profile modeling of PSR $\mathrm{J}0740+6620$, the most massive known pulsar, with data from the NICER and XMM-Newton observatories recently led to a measurement of its radius. We investigate this measurement's implications for the neutron star equation of state (EoS), employing a nonparametric EoS model based on Gaussian processes and combining information from other x-ray, radio and gravitational-wave observations of neutron stars. Our analysis mildly disfavors EoSs that support a disconnected hybrid star branch in the mass-radius relation, a proxy for strong phase transitions, with a Bayes factor of 6.9. For such EoSs, the transition mass from the hadronic to the hybrid branch is constrained to lie outside $(1,2)\text{ }\text{ }{\mathrm{M}}_{\ensuremath{\bigodot}}$. We also find that the conformal sound-speed bound is violated inside neutron star cores, which implies that the core matter is strongly interacting. The squared sound speed reaches a maximum of $0.7{5}_{\ensuremath{-}0.24}^{+0.25}{c}^{2}$ at ${3.60}_{\ensuremath{-}1.89}^{+2.25}$ times nuclear saturation…

The authors study the consequence of unitarity, causality and crossing on the forward $2\ensuremath{-}>2$ scattering amplitudes in quantum field theories. Out of an infinite set of energy dependent quantities, they identify an optimal finite subset of constraints, suitable to bound effective field theories at any finite order in the energy expansion. The study may help determine the acceptable range of validity of effective field theories in both couplings and energy.

We develop a number of novel ``black-bounce'' spacetimes. These are specific regular black holes where the area radius always remains nonzero, thereby leading to a ``throat'' that is either timelike (corresponding to a traversable wormhole), spacelike (corresponding to a ``bounce'' into a future universe), or null (corresponding to a ``one-way wormhole''). We first perform a general analysis of the regularity conditions for such a spacetime and then consider a number of specific examples. The examples are constructed using a mass function similar to that of Fan-Wang and fall into several particular cases, such as the original Simpson-Visser model, a Bardeen-type model, and other generalizations thereof. We analyze the regularity, energy conditions, and causal structure of these models. The main results are several new geometries, more complex than before, with two or more horizons, with the possibility of an extremal case. We derive a general theorem regarding static spacetime regularity and another general theorem regarding (non)satisfaction of the classical energy conditions.

The cosmological standard model ($\mathrm{\ensuremath{\Lambda}}$CDM) has recently come under pressure from measurements of the Hubble constant ${H}_{0}$, and theoretically from the swampland conjecture that emphasizes consistency with quantum gravity. The authors sweep through the typical class of string theory motivated dark-energy models, (coupled) quintessence with a clever expansion in low redshift and show that these models worsen the ${H}_{0}$ tension, but they also point to a gateway that might be tested with future $21c\phantom{\rule{0}{0ex}}m$ observations.

The authors report the first calculations for an SU(3) gauge theory on a quantum computer, with results for the time evolution. They emphasize how the continuous gauge fields are truncated and represented on quantum hardware and suggest benchmarks that can be used to quantify the performance.

The Muon g -2 Experiment at Fermi National Accelerator Laboratory (FNAL) has measured the muon anomalous precession frequency ω m a to an uncertainty of 434 parts per billion (ppb), statistical, and 56 ppb, systematic, with data collected in four storage ring configurations during its first physics run in 2018.When combined with a precision measurement of the magnetic field of the experiment's muon storage ring, the precession frequency measurement determines a muon magnetic anomaly of a μ ðFNALÞ ¼ 116 592 040ð54Þ × 10 -11 (0.46 ppm).This article describes the multiple techniques employed in the reconstruction, analysis, and fitting of the data to measure the precession frequency.It also presents the averaging of the results from the 11 separate determinations of ω m a , and the systematic uncertainties on the result.

New physics increasing the expansion rate just prior to recombination is among the least unlikely solutions to the Hubble tension and would be expected to leave an important signature in the early integrated Sachs-Wolfe (eISW) effect, a source of cosmic microwave background (CMB) anisotropies arising from the time variation of gravitational potentials when the Universe was not completely matter dominated. Why, then, is there no clear evidence for new physics from the CMB alone, and why does the $\mathrm{\ensuremath{\Lambda}}$ cold dark matter ($\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$) model fit CMB data so well? These questions and the vastness of the Hubble tension theory model space provide the motivation for general consistency tests of $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$. I perform an eISW-based consistency test of $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ introducing the parameter ${A}_{\mathrm{eISW}}$, which rescales the eISW contribution to the CMB power spectra. A fit to Planck CMB data yields ${A}_{\mathrm{eISW}}=0.988\ifmmode\pm\else\textpm\fi{}0.027$, in…

The problem of time in quantum gravity calls for a relational solution. Using quantum reduction maps, we establish a previously unknown equivalence between three approaches to relational quantum dynamics: (1) relational observables in the clock-neutral picture of Dirac quantization, (2) Page and Wootters' (PW) Schr\"odinger picture formalism, and (3) the relational Heisenberg picture obtained via symmetry reduction. Constituting three faces of the same dynamics, we call this equivalence the trinity. In the process, we develop a quantization procedure for relational Dirac observables using covariant positive operator-valued measures which encompass nonideal clocks and resolve the nonmonotonicity issue of realistic quantum clocks reported by Unruh and Wald. The quantum reduction maps reveal this procedure as the quantum analog of gauge-invariantly extending gauge-fixed quantities. We establish algebraic properties of these relational observables. We extend a recent ``clock-neutral'' approach to changing temporal reference frames, transforming relational observables and states, and…

In this work, we present black hole solutions with a cosmological constant in bumblebee gravity, which provides a mechanism for the Lorentz symmetry violation by assuming a nonzero vacuum expectation value for the bumblebee field. From the gravitational point of view, such solutions are spherically symmetric black holes with an effective cosmological constant and are supported by an anisotropic energy-momentum tensor, conceived of as the manifestation of the bumblebee field in the spacetime geometry. Then we calculate the shadow angular radius for the proposed black hole solution with a positive effective cosmological constant. In particular, our results are the very first relation between the bumblebee field and the shadow angular size.

We present the automation of one-loop computations in the standard-model effective field theory at dimension 6. Our general implementation, dubbed smeft@nlo, covers all types of operators: bosonic and two- and four-fermion ones. Included ultraviolet and rational counterterms presently allow for fully differential predictions, possibly matched to the parton shower, up to the one-loop level in the strong coupling or in four-quark operator coefficients. Exact flavor symmetries are imposed among light quark generations, and an initial focus is set on top-quark interactions in the fermionic sector. We illustrate the potential of this implementation with novel loop-induced and next-to-leading-order computations relevant for top-quark, electroweak, and Higgs-boson phenomenology at the LHC and future colliders.

We show that rotating black holes do not experience any tidal deformation when they are perturbed by a weak and adiabatic gravitational field. The tidal deformability of an object is quantified by the so-called ``Love numbers,'' which describe the object's linear response to its external tidal field. In this work, we compute the Love numbers of Kerr black holes and find that they vanish identically. We also compute the dissipative part of the black hole's tidal response, which is nonvanishing due to the absorptive nature of the event horizon. Our results hold for arbitrary values of black hole spin, for both the electric-type and magnetic-type perturbations, and to all orders in the multipole expansion of the tidal field. The boundary conditions at the event horizon and at asymptotic infinity are incorporated in our study, as they are crucial for understanding the way in which these tidal effects are mapped onto gravitational-wave observables. In closing, we address the ambiguity issue of Love numbers in general relativity, which we argue is resolved when those boundary conditions…

Krylov complexity, or K-complexity for short, has recently emerged as a new probe of chaos in quantum systems. It is a measure of operator growth in Krylov space, which conjecturally bounds the operator growth measured by the out of time ordered correlator (OTOC). We study Krylov complexity in conformal field theories by considering arbitrary 2d CFTs, free field, and holographic models. We find that the bound on OTOC provided by Krylov complexity reduces to bound on chaos of Maldacena, Shenker, and Stanford. In all considered examples including free and rational CFTs Krylov complexity grows exponentially, in stark violation of the expectation that exponential growth signifies chaos.

We revisit the possibilities of accommodating the experimental indications of the lepton flavor universality violation in $b$-hadron decays in the minimal scenarios in which the Standard Model is extended by the presence of a single $\mathcal{O}(1\text{ }\text{ }\mathrm{TeV})$ leptoquark state. To do so we combine the most recent low energy flavor physics constraints, including ${R}_{{K}^{(*)}}^{\mathrm{exp}}$ and ${R}_{{D}^{(*)}}^{\mathrm{exp}}$, and combine them with the bounds on the leptoquark masses and their couplings to quarks and leptons as inferred from the direct searches at the LHC and the studies of the large ${p}_{T}$ tails of the $pp\ensuremath{\rightarrow}\ensuremath{\ell}\ensuremath{\ell}$ differential cross section. We find that none of the scalar leptoquarks of ${m}_{\mathrm{LQ}}\ensuremath{\simeq}1\textdiv{}2\text{ }\text{ }\mathrm{TeV}$ can accommodate the $B$-anomalies alone. Only the vector leptoquark, known as ${U}_{1}$, can provide a viable solution which, in the minimal setup, provides an interesting prediction, i.e., a lower bound to the lepton flavor…

The imprint left on the cosmic microwave background (CMB) from CMB photons scattering off high-energy electrons in galaxies and clusters is known as the Sunyaev-Zel'dovich (SZ) effect and is the subject of these two papers from the Atacama Cosmology Telescope (ACT). ACT measurements combined with those of Planck and BOSS are shown to provide a rich picture of the electron gas thermodynamics of the galactic and cluster medium. This can be used to test and improve cosmological simulations relevant for upcoming experiments.

We revisit the impact of early dark energy (EDE) on galaxy clustering using BOSS galaxy power spectra, analyzed using the effective field theory (EFT) of large-scale structure (LSS) and anisotropies of the cosmic microwave background (CMB) from Planck. Recent studies found that these data place stringent constraints on the maximum abundance of EDE allowed in the Universe. We argue here that their conclusions are a consequence of their choice of priors on the EDE parameter space, rather than any disagreement between the data and the model. For example, when considering EFT-LSS, CMB, and high-redshift supernovae data we find the EDE and $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ models can provide statistically indistinguishable fits ($\mathrm{\ensuremath{\Delta}}{\ensuremath{\chi}}^{2}=0.12$) with a relatively large value for the maximum fraction of energy density in the EDE (${f}_{\mathrm{ede}}=0.09$) and Hubble constant (${H}_{0}=71\text{ }\text{ }\mathrm{km}/\mathrm{s}/\mathrm{Mpc}$) in the EDE model. Moreover, we demonstrate that the constraining power added from the inclusion…

We describe updates and improvements to the BayesWave gravitational wave transient analysis pipeline, and provide examples of how the algorithm is used to analyze data from ground-based gravitational wave detectors. BayesWave models gravitational wave signals in a morphology-independent manner through a sum of frame functions, such as Morlet-Gabor wavelets or chirplets. BayesWave models the instrument noise using a combination of a parametrized Gaussian noise component and nonstationary and non-Gaussian noise transients. Both the signal model and noise model employ trans-dimensional sampling, with the complexity of the model adapting to the requirements of the data. The flexibility of the algorithm makes it suitable for a variety of analyses, including reconstructing generic unmodeled signals; cross-checks against modeled analyses for compact binaries; as well as separating coherent signals from incoherent instrumental noise transients (glitches). The BayesWave model has been extended to account for gravitational wave signals with generic polarization content and the simultaneous…

Results of a search for new physics in final states with an energetic jet and large missing transverse momentum are reported. The search uses proton-proton collision data corresponding to an integrated luminosity of $139\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ at a center-of-mass energy of 13 TeV collected in the period 2015--2018 with the ATLAS detector at the Large Hadron Collider. Compared to previous publications, in addition to an increase of almost a factor of four in the data size, the analysis implements a number of improvements in the signal selection and the background determination leading to enhanced sensitivity. Events are required to have at least one jet with transverse momentum above 150 GeV and no reconstructed leptons ($e$, $\ensuremath{\mu}$ or $\ensuremath{\tau}$) or photons. Several signal regions are considered with increasing requirements on the missing transverse momentum starting at 200 GeV. Overall agreement is observed between the number of events in data and the Standard Model predictions. Model-independent 95% confidence-level limits on visible…

Gravitational waves can provide an accurate measurement of the luminosity distance to the source but cannot provide the source redshift unless the degeneracy between mass and redshift can be broken. This makes it essential to infer the redshift of the source independently to measure the expansion history of the Universe. We show that by exploiting the clustering scale of the gravitational wave sources with galaxies of a known redshift, we can infer the expansion history from redshift unknown gravitational wave sources. By using gravitational wave sources of unknown redshift that are detectable from the network of gravitational wave detectors with Advanced LIGO design sensitivity, we will be able to obtain accurate and precise measurements of the local Hubble constant, the expansion history of the Universe, and the gravitational wave bias parameter, which captures the distribution of gravitational wave sources with respect to the redshift tracer distribution. While we showcase its application to low redshift gravitational waves, this technique will be applicable also to the high…

General relativity can be formulated equivalently with a non-Riemannian geometry that associates with an affine connection of nonzero nonmetricity $Q$ but vanishing curvature $R$ and torsion $T$. Modification based on this description of gravity generates the $f(Q)$ gravity. In this work, we explore the application of $f(Q)$ gravity to the spherically symmetric configurations. We discuss the gauge fixing and connections in this setting. We demonstrate the effects of $f(Q)$ by considering the external and internal solutions of compact stars. The external background solutions for any regular form of $f(Q)$ coincide with the corresponding solutions in general relativity, i.e., the Schwarzschild--de Sitter solution and the Reissner--Nordstr\"om--de Sitter solution with an electromagnetic field. For internal structure, with a simple model $f(Q)=Q+\ensuremath{\alpha}{Q}^{2}$ and a polytropic equation of state, we find that a negative modification ($\ensuremath{\alpha}<0$) provides support to more stellar masses while a positive one ($\ensuremath{\alpha}>0$) reduces the amount of matter of…

Hubble tension is routinely presented as a mismatch between the Hubble constant ${H}_{0}$ determined locally and a value inferred from the flat $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ cosmology. In essence, the tension boils down to a disagreement between two numbers. Here, assuming the tension is cosmological in origin, we predict that within flat $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ there should be other inferred values of ${H}_{0}$, and that a ``running of ${H}_{0}$ with redshift'' can be expected. These additional determinations of ${H}_{0}$ may be traced to a difference between the effective equation of state (EoS) of the Universe within the Friedmann-Lema\^{\i}tre-Robertson-Walker (FLRW) cosmology framework and the current standard model. We introduce a diagnostic that flags such a running of ${H}_{0}$.

Statistical modeling is a key component in the extraction of physical results from lattice field theory calculations. Although the general models used are often strongly motivated by physics, many model variations can frequently be considered for the same lattice data. Model averaging, which amounts to a probability-weighted average over all model variations, can incorporate systematic errors associated with model choice without being overly conservative. We discuss the framework of model averaging from the perspective of Bayesian statistics, and give useful formulas and approximations for the particular case of least-squares fitting, commonly used in modeling lattice results. In addition, we frame the common problem of data subset selection (e.g., choice of minimum and maximum time separation for fitting a two-point correlation function), as a model selection problem and study model averaging as a straightforward alternative to manual selection of fit ranges. Numerical examples involving both mock and real lattice data are given.

Over the last years some interest has been gathered by $f(Q)$ theories, which are new candidates to replace Einstein's prescription for gravity. The nonmetricity tensor $Q$ allows to put forward the assumption of a free torsionless connection and, consequently, new degrees of freedom in the action are taken into account. This work focuses on a class of $f(Q)$ theories, characterized by the presence of a general power-law term which adds up to the standard (linear in) $Q$ term in the action, and on new cosmological scenarios arising from them. Using the Markov chain Monte Carlo method, we carry out statistical tests relying upon background data such as Type Ia supernovae luminosities and direct Hubble data (from cosmic clocks), along with cosmic microwave background shift and baryon acoustic oscillations data. This allows us to perform a multifaceted comparison between these new cosmologies and the (concordance) $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ setup. We conclude that, at the current precision level, the best fits of our $f(Q)$ models correspond to values of their specific…

We introduce a systematic and direct procedure to generate hairy rotating black holes by deforming a spherically symmetric seed solution. We develop our analysis in the context of the gravitational decoupling approach, without resorting to the Newman-Janis algorithm. As examples of possible applications, we investigate how the Kerr black hole solution is modified by a surrounding fluid with conserved energy-momentum tensor. We find nontrivial extensions of the Kerr and Kerr-Newman black holes with primary hair. We prove that a rotating and charged black hole can have the same horizon as Kerr's, Schwarzschild's, or Reissner-Nordstr\"om's, thus showing possible observational effects of matter around black holes.

Primordial black holes formed in the early Universe via gravitational collapse of over-dense regions may contribute a significant amount to the present dark matter relic density. Inflation provides a natural framework for the production mechanism of primordial black holes. For example, single field inflation models with a fine-tuned scalar potential may exhibit a period of ultra-slow roll, during which the curvature perturbation may be enhanced to become seeds of the primordial black holes formed as the corresponding scales reenter the horizon. In this work, we propose an alternative mechanism for the primordial black hole formation. We consider a model in which a scalar field is coupled to the Gauss-Bonnet term and show that primordial black holes may be seeded when a scalar potential term and the Gauss-Bonnet coupling term are nearly balanced. Large curvature perturbation in this model not only leads to the production of primordial black holes, but it also sources gravitational waves at the second order. We calculate the present density parameter of the gravitational waves and…

The primordial scalar power spectrum is well constrained by the cosmological data on large scales, primarily from the observations of the anisotropies in the cosmic microwave background. Over the last few years, it has been recognized that a sharp rise in power on small scales will lead to the enhanced formation of primordial black holes (PBHs) and also generate secondary gravitational waves (GWs) of higher and, possibly, detectable amplitudes. It is well understood that scalar power spectra with COBE normalized amplitude on the cosmic microwave background scales and enhanced amplitudes on smaller scales can be generated due to deviations from slow roll in single, canonical scalar field models of inflation. In fact, an epoch of so-called ultraslow roll inflation can lead to the desired amplification. We find that scenarios that lead to ultraslow roll can be broadly classified into two types, one wherein there is a brief departure from inflation (a scenario referred to as punctuated inflation) and another wherein such a departure does not arise. In this work, we consider a set of…

Symmetric teleparallel gravity theories, in which the gravitational interaction is attributed to the nonmetricity of a flat, symmetric, but not metric-compatible affine connection, have been a topic of growing interest in recent studies. Numerous works study the cosmology of symmetric teleparallel gravity assuming a flat Friedmann-Lema\^{\i}tre-Robertson-Walker metric, while working in the so-called ``coincident gauge,'' further assuming that the connection coefficients vanish. However, little attention has been paid to the fact that both of these assumptions rely on the freedom to choose a particular coordinate system in order to simplify the metric or the connection, and that they may, in general, not be achieved simultaneously. Here we construct the most general symmetric teleparallel geometry obeying the conditions of homogeneity and isotropy, without making any assumptions on the properties of the coordinates, and present our results in both the usual cosmological coordinates and in the coincident gauge. We find that in general these coordinates do not agree, and that assuming…

We formulate a version of the information paradox in de Sitter spacetime and show that it is solved by the emergence of entanglement islands in the context of the De Sitter/de Sitter correspondence; in particular, the entanglement entropy of a subregion obeys a time-dependent Page curve. Our construction works in general spacetime dimensions and keeps the graviton massless. We interpret the resulting behavior of the entanglement entropy using double holography. It suggests that the spatial distribution of microscopic degrees of freedom depends on descriptions, as in the case of a black hole. In the static (distant) description of de Sitter (black hole) spacetime, these degrees of freedom represent microstates associated with the Gibbons-Hawking (Bekenstein-Hawking) entropy and are localized toward the horizon. On the other hand, in a global (effective two-sided) description, which is obtained by the quantum analog of analytic extension and is intrinsically semiclassical, they are distributed uniformly and in a unique semiclassical de Sitter (black hole) vacuum state.

We provide a theoretical model of $F(R)$ gravity in which it is possible to describe in a unified way inflation, an early and a late dark energy era, in the presence of a light axion particle which plays the role of the dark matter component of the Universe. Particularly, the early time phenomenology is dominated by an ${R}^{2}$ term, while the presence of the other terms $f(R)$ ensure the occurrence of the early and late-time dark energy eras. The inflationary phenomenology is compatible with the Planck 2018 data for inflation, while the late-time dark energy era is compatible with the Planck 2018 constraints on the cosmological parameters. Also, the model exhibits an early dark energy era, at $z\ensuremath{\sim}2.5$ approximately, followed by a deceleration era, which starts at approximately $z\ensuremath{\sim}1.5$, which in turn is followed by a late-time dark energy era for redshifts $z\ensuremath{\sim}0.5$, which lasts for approximately 5 billion years up to present time. A notable feature of our model is that the dark energy era is free from dark energy oscillations, at least…

A haloscope of the QUAX--$a\ensuremath{\gamma}$ experiment composed of an oxygen-free high thermal conductivity-Cu cavity inside an 8.1 T magnet and cooled to $\ensuremath{\sim}200\text{ }\text{ }\mathrm{mK}$ is put in operation for the search of galactic axion with mass ${m}_{a}\ensuremath{\simeq}43\text{ }\text{ }\ensuremath{\mu}\mathrm{eV}$. The power emitted by the resonant cavity is amplified with a Josephson parametric amplifier whose noise fluctuations are at the standard quantum limit. With the data collected in about 1 h at the cavity frequency ${\ensuremath{\nu}}_{c}=10.40176\text{ }\text{ }\mathrm{GHz}$, the experiment reaches the sensitivity necessary for the detection of galactic QCD-axion, setting the 90% confidence level limit to the axion-photon coupling ${g}_{a\ensuremath{\gamma}\ensuremath{\gamma}}<0.766\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}13}\text{ }\text{ }{\mathrm{GeV}}^{\ensuremath{-}1}$.

Building on previous work (https://journals.aps.org/prd/abstract/10.1103/PhysRevD.97.123513), the authors study through extensive numerical simulations the possibility of observing the gravitational wave spectrum created in a first-order phase transition (in beyond the standard model theories) in upcoming space-based detectors like LISA. Different effective potentials are considered and it is shown that the potential could be determined by the form of the gravitational wave spectrum.

We study observational constraints on the nonmetricity $f(Q)$-gravity which reproduces an exact $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ background expansion history while modifying the evolution of linear perturbations. To this purpose we use cosmic microwave background (CMB) radiation, baryonic acoustic oscillations (BAO), redshift-space distortions (RSD), supernovae type Ia (SNIa), galaxy clustering (GC) and weak gravitational lensing (WL) measurements. We set stringent constraints on the parameter of the model controlling the modifications to the gravitational interaction at linear perturbation level. We find the model to be statistically preferred by data over the $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ according to the ${\ensuremath{\chi}}^{2}$ and deviance information criterion statistics for the combination with CMB, BAO, RSD and SNIa. This is mostly associated to a better fit to the low-$\ensuremath{\ell}$ tail of CMB temperature anisotropies.

We present a model of early modified gravity (EMG) consisting in a scalar field $\ensuremath{\sigma}$ with a nonminimal coupling to the Ricci curvature of the type ${M}_{\mathrm{pl}}^{2}+\ensuremath{\xi}{\ensuremath{\sigma}}^{2}$ plus a cosmological constant and a small effective mass and demonstrate its ability to alleviate the ${H}_{0}$ tension while providing a good fit to cosmic microwave background (CMB) anisotropies and baryon acoustic oscillations (BAO) data. In this model the scalar field, frozen deep in the radiation era, grows around the redshift of matter-radiation equality because of the coupling to nonrelativistic matter. The small effective mass, which we consider here as induced by a quartic potential, then damps the scalar field into coherent oscillations around its minimum at $\ensuremath{\sigma}=0$, leading to a weaker gravitational strength at early times and naturally recovering the consistency with laboratory and Solar System tests of gravity. We analyze the capability of EMG with positive $\ensuremath{\xi}$ to fit current cosmological observations and compare…

Primordial black holes (PBHs) might be formed in the early Universe and could comprise at least a fraction of the dark matter. Using the recently released GWTC-2 dataset from the third observing run of the LIGO-Virgo Collaboration, we investigate whether current observations are compatible with the hypothesis that all black hole mergers detected so far are of primordial origin. We constrain PBH formation models within a hierarchical Bayesian inference framework based on deep learning techniques, finding best-fit values for distinctive features of these models, including the PBH initial mass function, the fraction of PBHs in dark matter, and the accretion efficiency. The presence of several spinning binaries in the GWTC-2 dataset favors a scenario in which PBHs accrete and spin up. Our results indicate that PBHs may comprise only a fraction smaller than 0.3% of the total dark matter, and that the predicted PBH abundance is still compatible with other constraints.

The open question of whether a Kerr black hole can become tidally deformed or not has profound implications for fundamental physics and gravitational-wave astronomy. We consider a Kerr black hole embedded in a weak and slowly varying, but otherwise arbitrary, multipolar tidal environment. By solving the static Teukolsky equation for the gauge-invariant Weyl scalar ${\ensuremath{\psi}}_{0}$ and by reconstructing the corresponding metric perturbation in an ingoing radiation gauge, for a general harmonic index $\ensuremath{\ell}$, we compute the linear response of a Kerr black hole to the tidal field. This linear response vanishes identically for a Schwarzschild black hole and for an axisymmetric perturbation of a spinning black hole. For a nonaxisymmetric perturbation of a spinning black hole, however, the linear response does not vanish, and it contributes to the Geroch-Hansen multipole moments of the perturbed Kerr geometry. As an application, we compute explicitly the rotational black hole tidal Love numbers that couple the induced quadrupole moments to the quadrupolar tidal…

Building upon recent work, we present an improved effective-one-body (EOB) model for spin-aligned, coalescing, black hole binaries with generic orbital configurations, i.e., quasicircular, eccentric, or hyperbolic orbits. The model, called TEOBResumSGeneral, relies on the idea of incorporating general Newtonian prefactors, instead of the usual quasicircular ones, in both radiation reaction and waveform. The major advance with respect to previous work is that the quasicircular limit of the model is now correctly informed by numerical relativity (NR) quasicircular simulation. This provides EOB/NR unfaithfulness for the dominant quadrupolar waveform, calculated with Advanced LIGO noise, at most of the order of 1% over a meaningful portion of the quasicircular NR simulations computed by the Simulating eXtreme Spacetime (SXS) collaboration. In the presence of eccentricity, the model is similarly NR-faithful, $\ensuremath{\lesssim}1%$, all over the 28 public SXS NR datasets, with initial eccentricity up to $\ensuremath{\simeq}0.2$, mass ratio up to $q=3$ and dimensionless spin magnitudes…

Taking QED effect into account, we investigate the shadows of a static black hole with magnetic monopoles and neutral black holes in magnetic fields through the numerical backward ray-tracing method. For a static black holes with a magnetic monopole, we obtain the relation between the shadow radius and the coupling constant. For neutral black holes in uniform magnetic fields, we find that the shadow curves deviate very little from the ellipses for an equatorial observer, and we read the linear relation between the eccentricity and the coupling constant. For ${\ensuremath{\theta}}_{o}\ensuremath{\ne}\ensuremath{\pi}/2$, we find that the shadow curves can be well approximated by ellipses in most cases, except when the magnetic field is very strong and the observer sits around the angle ${\ensuremath{\theta}}_{o}=\ensuremath{\pi}/4$ or $3\ensuremath{\pi}/4$. Moreover, we extend our investigation to a neutral static black hole surrounded by a current loop.

We present a novel method for sampling iso-likelihood contours in nested sampling using a type of machine learning algorithm known as normalizing flows and incorporate it into our sampler nessai. nessai is designed for problems where computing the likelihood is computationally expensive and therefore the cost of training a normalizing flow is offset by the overall reduction in the number of likelihood evaluations. We validate our sampler on 128 simulated gravitational wave signals from compact binary coalescence and show that it produces unbiased estimates of the system parameters. Subsequently, we compare our results to those obtained with dynesty and find good agreement between the computed log-evidences while requiring 2.07 times fewer likelihood evaluations. We also highlight how the likelihood evaluation can be parallelized in nessai without any modifications to the algorithm. Finally, we outline diagnostics included in nessai and how these can be used to tune the sampler's settings.

Recently, the image of a Schwarzschild black hole with an accretion disk has been revisited, and it showed that the ``photon ring,'' defined as highly bent light rays that intersect the disk plane more than twice, is extremely narrow and makes a negligible contribution to the total brightness. In this paper, we investigate the observational appearance of an optically and geometrically thin accretion disk around a hairy black hole in an Einstein-Maxwell-scalar model. Intriguingly, we find that in a certain parameter regime, due to an extra maximum or an ``anklelike'' structure in the effective potential for photons, the photon ring can be remarkably wide, thus making a notable contribution to the flux of the observed image. In particular, there appears a wide and bright annulus, which comprises multiple concentric bright thin rings with different luminosity, in the high resolution image.

We study the gravitational radiation emitted during the scattering of two spinless bodies in the post-Minkowskian effective field theory approach. We derive the conserved stress-energy tensor linearly coupled to gravity and the classical probability amplitude of graviton emission at leading and next-to-leading order in the Newton's constant $G$. The amplitude can be expressed in compact form as one-dimensional integrals over a Feynman parameter involving Bessel functions. We use it to recover the leading-order radiated angular momentum expression. Upon expanding it in the relative velocity between the two bodies $v$, we compute the total four-momentum radiated into gravitational waves at leading-order in $G$ and up to an order ${v,}^{8}$ finding agreement with what was recently computed using scattering amplitude methods. Our results also allow us to investigate the zero frequency limit of the emitted energy spectrum.

We compute adiabatic waveforms for extreme mass-ratio inspirals (EMRIs) by ``stitching'' together a long inspiral waveform from a sequence of waveform snapshots, each of which corresponds to a particular geodesic orbit. We show that the complicated total waveform can be regarded as a sum of ``voices.'' Each voice evolves in a simple way on long timescales, a property which can be exploited to efficiently produce waveform models that faithfully encode the properties of EMRI systems. We look at examples for a range of different orbital geometries: spherical orbits, equatorial eccentric orbits, and one example of generic (inclined and eccentric) orbits. To our knowledge, this is the first calculation of a generic EMRI waveform that uses strong-field radiation reaction. We examine waveforms in both the time and frequency domains. Although EMRIs evolve slowly enough that the stationary phase approximation (SPA) to the Fourier transform is valid, the SPA calculation must be done to higher order for some voices, since their instantaneous frequency can change from chirping forward…

Knowledge of the shape of the mass spectrum of compact objects can be used to help break the degeneracy between the mass and redshift of the gravitational wave (GW) sources and thus can be used to infer cosmological parameters in the absence of redshift measurements obtained from electromagnetic observations. In this paper, we study extensively different aspects of this approach, including its computational limits and achievable accuracy. Focusing on ground-based detectors with current and future sensitivities, we first perform the analysis of an extensive set of simulated data using a hierarchical Bayesian scheme that jointly fits the source population and cosmological parameters. We consider a population model (power-law plus Gaussian) which exhibits characteristic scales (extremes of the mass spectrum, presence of an accumulation point modeled by a Gaussian peak) that allow an indirect estimate of the source redshift. Our analysis of this catalog highlights and quantifies the tight interplay between source population and cosmological parameters, as well as the influence of…

The imprint left on the cosmic microwave background (CMB) from CMB photons scattering off high-energy electrons in galaxies and clusters is known as the Sunyaev-Zel'dovich (SZ) effect and is the subject of these two papers from the Atacama Cosmology Telescope (ACT). ACT measurements combined with those of Planck and BOSS are shown to provide a rich picture of the electron gas thermodynamics of the galactic and cluster medium. This can be used to test and improve cosmological simulations relevant for upcoming experiments.

We present here up-to-date neutrino mass limits exploiting the most recent cosmological data sets. By making use of the cosmic microwave background temperature fluctuation and polarization measurements, supernovae Ia luminosity distances, baryon acoustic oscillation observations and determinations of the growth rate parameter, we are able to set the most constraining bound to date, $\ensuremath{\sum}{m}_{\ensuremath{\nu}}<0.09\text{ }\text{ }\mathrm{eV}$ at 95% C.L. This very tight limit is obtained without the assumption of any prior on the value of the Hubble constant and highly compromises the viability of the inverted mass ordering as the underlying neutrino mass pattern in nature. The results obtained here further strengthen the case for very large multitracer spectroscopic surveys as unique laboratories for cosmological relics, such as neutrinos: that would be the case of the Dark Energy Spectroscopic Instrument survey and of the Euclid mission.

The space-based gravitational wave detector LISA will observe mergers of massive black hole binary systems (MBHBs) to cosmological distances, as well as inspiralling stellar-origin (or stellar-mass) binaries (SBHBs) years before they enter the LIGO/Virgo band. Much remains to be explored for the parameter recovery of both classes of systems. Previous MBHB analyses relied on inspiral-only signals and/or a simplified Fisher matrix analysis, while SBHBs have not yet been extensively analyzed with Bayesian methods. We accelerate likelihood computations by (i) using a Fourier-domain response of the LISA instrument, (ii) using a reduced order model for nonspinning waveforms that include a merger-ringdown and higher harmonics, and (iii) setting the noise realization to zero and computing overlaps in the amplitude/phase representation. We present the first simulations of Bayesian inference for the parameters of massive black hole systems including consistently the merger and ringdown of the signal, as well as higher harmonics. We clarify the roles of LISA response time and frequency…

Extreme mass ratio inspirals (EMRIs) are important sources for space-borne gravitational wave detectors, such as the laser interferometer space antenna and TianQin. Previous EMRI rate studies have focused on the ``loss cone'' scenario, where stellar-mass black holes (sBHs) are scattered into highly eccentric orbits near the central massive black hole (MBH) via multibody interaction. In this work, we calculate the rate of EMRIs of an alternative formation channel: EMRI formation assisted by the accretion flow around accreting massive black holes. In this scenario, sBHs and stars on inclined orbits are captured by the accretion disk, and then subsequently migrate towards the MBH, under the influence of density wave generation and head wind. By solving the Fokker-Planck equation incorporating both sBH-sBH--sBH-star scatterings and sBH--star-disk interactions, we find that an accretion disk usually boosts the EMRI formation rate per individual MBH by $\mathcal{O}({10}^{1}--{10}^{3})$ compared with the canonical loss cone formation channel. Taking into account that the fraction of active…

In this paper, we obtain an effective metric describing a regular and rotating magnetic black hole (BH) solution with a Yang-Mills electromagnetic source in Einstein-Yang-Mills (EYM) theory using the Newman-Janis (NJ) algorithm via the noncomplexification radial coordinate procedure. We then study the BH shadow and the quasinormal modes (QNMs) for massless scalar and electromagnetic fields and the quasiperiodic oscillations (QPOs). To this end, we also study the embedding diagram for the rotating EYM BH. The energy conditions, shadow curvature radius, topology, and the dynamical evolution of scalar and electromagnetic perturbations using the time domain integration method are investigated. We show that the shadow radius decreases by increasing the magnetic charge, while the real part of QNMs of scalar and electromagnetic fields increases by increasing the magnetic charge. This result is consistent with the inverse relation between the shadow radius and the real part of QNMs. In addition, we have studied observational constraints on the EYM parameter $\ensuremath{\lambda}$ via…

Hamiltonian formulation of lattice gauge theories (LGTs) is the most natural framework for the purpose of quantum simulation, an area of research that is growing with advances in quantum-computing algorithms and hardware. It, therefore, remains an important task to identify the most accurate, while computationally economic, Hamiltonian formulation(s) in such theories, considering the necessary truncation imposed on the Hilbert space of gauge bosons with any finite computing resources. This paper is a first step toward addressing this question in the case of non-Abelian LGTs. Such theories require the imposition of non-Abelian Gauss's laws on the Hilbert space, introducing additional computational complexity. Focusing on the case of SU(2) LGT in $1+1$ dimensions coupled to one flavor of fermionic matter, a number of different formulations of the original Kogut-Susskind framework are analyzed with regard to the dependence of the dimension of the physical Hilbert space on boundary conditions, system size, and the cutoff on the excitations of gauge bosons. The impact of such…

Gravitational wave observations of compact binaries allow us to test general relativity (and modifications thereof) in the strong and highly dynamical field regime of gravity. Here, we confront two extensions to general relativity, dynamical Chern-Simons, and Einstein-dilaton-Gauss-Bonnet theories, against the gravitational wave sources from the GWTC-1 and GWTC-2 catalogs by the LIGO-Virgo Collaboration. By stacking the posterior of individual events, we strengthen the constraint on the square root of the coupling parameter in Einstein-dilaton-Gauss-Bonnet gravity to $\sqrt{{\ensuremath{\alpha}}_{\mathrm{EdGB}}}<1.7\text{ }\text{ }\mathrm{km}$, but we are unable to place meaningful constraints on dynamical Chern-Simons gravity. Importantly, we also show that our bounds are robust to (i) the choice of general-relativity base waveform model, upon which we add modifications, (ii) unknown higher post-Newtonian order terms in the modifications to general relativity, (iii) the small-coupling approximation, and (iv) uncertainties on the nature of the constituent compact objects.

The mismatch in the value of the Hubble constant from low- and high-redshift observations may be recast as a discrepancy between the low- and high-redshift determinations of the luminosity of Type Ia supernovae, the latter featuring an absolute magnitude which is $\ensuremath{\approx}0.2\text{ }\text{ }\mathrm{mag}$ lower. Here, we propose that a rapid transition in the value of the relative effective gravitational constant ${\ensuremath{\mu}}_{G}\ensuremath{\equiv}\frac{{G}_{\mathrm{eff}}}{{G}_{N}}$ at ${z}_{t}\ensuremath{\simeq}0.01$ could explain the lower luminosity (higher magnitude) of local supernovae, thus solving the ${H}_{0}$ crisis. In other words, here the tension is solved by featuring a transition at the perturbative rather than background level. A model that features ${\ensuremath{\mu}}_{G}=1$ for $z\ensuremath{\lesssim}0.01$ but ${\ensuremath{\mu}}_{G}\ensuremath{\simeq}0.9$ for $z\ensuremath{\gtrsim}0.01$ is trivially consistent with local gravitational constraints but would raise the Chandrasekhar mass and so decrease the absolute magnitude of type Ia supernovae at…

We introduce a new quantity, called pseudo-entropy, as a generalization of entanglement entropy via postselection. We expect this quantity to provide a new class of order parameters in quantum many-body systems. In the anti--de Sitter space (AdS)/conformal field theory (CFT) correspondence, this quantity is dual to areas of minimal area surfaces in time-dependent Euclidean spaces which are asymptotically AdS. We call this geometric computation of pseudo-entropy via the $\mathrm{AdS}/\mathrm{CFT}$ the holographic pseudo-entropy. We study its basic properties and classifications in qubit systems. In specific examples, we provide a quantum information theoretic meaning of this new quantity as an averaged number of Bell pairs when the post-selection is performed. We also present properties of the pseudo-entropy for random states. We then calculate the pseudo-entropy in the presence of local operator excitations for both the two dimensional free massless scalar CFT and two dimensional holographic CFTs. We find a general property in CFTs that the pseudo-entropy is highly reduced when the…

Inspired by the recent conjecture originated from graduated dark energy that the Universe has recently transitioned from anti--de Sitter vacua to de Sitter vacua, we extend the standard $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ model by a cosmological constant (${\mathrm{\ensuremath{\Lambda}}}_{s}$) that switches sign at a certain redshift ${z}_{\ifmmode\dagger\else\textdagger\fi{}}$, and we call this model ${\mathrm{\ensuremath{\Lambda}}}_{s}\mathrm{CDM}$. We discuss the construction and theoretical features of this model in detail and find out that, when the consistency of the ${\mathrm{\ensuremath{\Lambda}}}_{s}\mathrm{CDM}$ model with the cosmic microwave background (CMB) data is ensured, (i) ${z}_{\ifmmode\dagger\else\textdagger\fi{}}\ensuremath{\gtrsim}1.1$ is implied by the condition that the Universe monotonically expands, (ii) ${H}_{0}$ and ${M}_{B}$ (type Ia supernovae absolute magnitude) values are inversely correlated with ${z}_{\ifmmode\dagger\else\textdagger\fi{}}$ and reach ${H}_{0}\ensuremath{\approx}74.5\text{ }\text{ }\mathrm{km}\text{…

Assessing the probability that two or more gravitational wave (GW) events are lensed images of the same source requires an understanding of the properties of the lensed images. For short enough wavelengths where wave effects can be neglected, lensed images will generically have a fixed relative phase shift that needs to be taken into account in the lensing hypothesis. For nonprecessing, circular binaries dominated by quadrupole radiation, these lensing phase shifts are degenerate with either a shift in the coalescence phase or a detector and inclination-dependent shift in the orientation angle. This degeneracy is broken by the presence of higher harmonic modes with $|m|\ensuremath{\ne}2$ in the former and $|m|\ensuremath{\ne}l$ in the latter. The presence of precession or eccentricity will also break this degeneracy. This implies that a lensed GW image will not necessarily be consistent with (unlensed) predictions from general relativity (GR). Therefore, unlike the conventional scenario of electromagnetic waves, strong lensing of GWs can lead to images with a modified phase…

We develop a model-independent procedure to single out static and spherically symmetric wormhole solutions based on the general relativistic Poynting-Robertson effect and the extension of the ray-tracing formalism in generic static and spherically symmetric wormhole metrics. Simulating the flux emitted by the Poynting-Robertson critical hypersurface (i.e., a stable structure where gravitational and radiation forces attain equilibrium) or also from another x-ray source in these general geometrical environments toward a distant observer, we are able to reconstruct, only locally to the emission region, the wormhole solutions which are in agreement with the high-energy astrophysical observational data. This machinery works only if wormhole evidences have been detected. Indeed, in our previous paper we showed how the Poynting-Robertson critical hypersurfaces can be located in regions of strong gravitational field and become valuable astrophysical probe to observationally search for wormholes' existence. As examples, we apply our method to selected wormhole solutions in different extended…

We perform a unitary coupled channel study of the interaction of the ${D}^{*+}{D}^{0},{D}^{*0}{D}^{+}$ channels and find a state barely bound, very close to isospin $I=0$. We take the experimental mass as input and obtain the width of the state and the ${D}^{0}{D}^{0}{\ensuremath{\pi}}^{+}$ mass distribution. When the mass of the ${T}_{cc}$ state quoted in the experimental paper from raw data is used, the width obtained is of the order of the 80 keV, small compared to the value given in that work. Yet, when the mass obtained in an analysis of the data considering the experimental resolution is taken, the width obtained is about 43 keV and both the width and the ${D}^{0}{D}^{0}{\ensuremath{\pi}}^{+}$ mass distribution are in remarkable agreement with the results obtained in that latter analysis.

The authors use numerical bootstrap methods to determine with unprecedented accuracy CFT data of the critical $O(3)$ model which describes the critical behaviour of isotropic magnets. The crucial question for this model is its stability under perturbations that may mimic anisotropies of natural magnets. Implementing new algorithms, it is proven that the model is unstable and therefore not the critical point of realistic, not specially fine-tuned magnets.

The Laser Interferometer Space Antenna (LISA) mission, scheduled for launch in the early 2030s, is a gravitational wave observatory in space designed to detect sources emitting in the millihertz band. In contrast to the present ground-based detectors, the LISA data are expected to be a signal dominated, with strong and weak gravitational wave signals overlapping in time and in frequency. Astrophysical population models predict a sufficient number of signals in the LISA band to blend together and form an irresolvable foreground noise. In this work, we present a generic method for characterizing the foreground signals originating from a given astrophysical population of coalescing compact binaries. Assuming idealized detector conditions and a perfect data analysis technique capable of identifying and removing the bright sources, we apply an iterative procedure which allows us to predict the different levels of foreground noise.

We consider the direct $s$-channel gravitational production of dark matter during the reheating process. Independent of the identity of the dark matter candidate or its nongravitational interactions, the gravitational process is always present and provides a minimal production mechanism. During reheating, a thermal bath is quickly generated with a maximum temperature ${T}_{\mathrm{max}}$, and the temperature decreases as the inflaton continues to decay until the energy densities of radiation and inflaton oscillations are equal, at ${T}_{\mathrm{RH}}$. During these oscillations, $s$-channel gravitational production of dark matter occurs. We show that the abundance of dark matter (fermionic or scalar) depends primarily on the combination ${T}_{\mathrm{max}}^{4}/{T}_{\mathrm{RH}}{M}_{P}^{3}$. We find that a sufficient density of dark matter can be produced over a wide range of dark matter masses: from 1 GeV to 1 ZeV.

In high-energy leptonic collisions well above the electroweak scale, the collinear splitting mechanism of the electroweak gauge bosons becomes the dominant phenomena via the initial state radiation and the final state showering. We point out that at future high-energy lepton colliders, such as a multi-TeV muon collider, the electroweak parton distribution functions (EW PDFs) should be adopted as the proper description for partonic collisions of the initial states. The leptons and electroweak gauge bosons are the EW partons, that evolve according to the unbroken Standard Model (SM) gauge group and that effectively resum potentially large collinear logarithms. We present a formalism for the EW PDFs at the leading-log (LL) accuracy. We calculate semi-inclusive cross sections for some important SM processes at a future multi-TeV muon collider. We conclude that it is appropriate to adopt the EW PDF formalism for future high-energy lepton colliders.

The PROSPECT Collaboration presents their improved results with new limits on the oscillation of electron antineutrinos to light sterile neutrinos and energy spectrum measurements with several short baselines.

In this paper we take the first steps towards bridging the gap between the conformal and cosmological bootstrap programs. We present a simple general relation between tree-level exchanges in anti-de Sitter (AdS) and de Sitter (dS) space with Bunch-Davies intial conditions, providing a complete AdS to dS dictionary at tree-level. This allows us to directly import techniques and results for conformal field theory correlators dual to AdS-Witten diagrams to boundary correlation functions in dS. We apply this relation to extend various indispensable tools from the conformal bootstrap to boundary correlation functions in dS, including Mellin amplitudes and the spectral representation for dS exchanges. We also derive their conformal block decomposition, both in the direct and crossed channels, from their AdS counterparts. The relation between AdS and dS exchanges itself is derived using a recently introduced Mellin-Barnes representation for boundary correlators in momentum space, where (A)dS exchanges are straightforwardly fixed by a combination of factorization, conformal symmetry and…

A constant early dark energy (EDE) component contributing a fraction ${f}_{\mathrm{EDE}}({z}_{c})\ensuremath{\sim}10%$ of the energy density of the universe around ${z}_{c}\ensuremath{\simeq}3500$ and diluting as or faster than radiation afterwards, can provide a simple resolution to the Hubble tension, the $\ensuremath{\sim}5\ensuremath{\sigma}$ discrepancy---in the $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ context---between the ${H}_{0}$ value derived from early- and late-universe observations. However, it has been pointed out that including Large-Scale Structure (LSS) data, which are in $\ensuremath{\sim}3\ensuremath{\sigma}$ tension with $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ and EDE cosmologies, might break some parameter degeneracy and alter these conclusions. We reassess the viability of the EDE against a host of high- and low-redshift measurements, by combining LSS observations from recent weak lensing (WL) surveys with CMB, baryon acoustic oscillation (BAO), growth function (FS) and Supernova Ia (SNIa) data. Introducing a model whose only parameter is…

We develop new strategies to build numerical relativity surrogate models for eccentric binary black hole systems, which are expected to play an increasingly important role in current and future gravitational-wave detectors. We introduce a new surrogate waveform model, NRSur2dq1Ecc, using 47 nonspinning, equal-mass waveforms with eccentricities up to 0.2 when measured at a reference time of $5500M$ before merger. This is the first waveform model that is directly trained on eccentric numerical relativity simulations and does not require that the binary circularizes before merger. The model includes the (2,2), (3,2), and (4,4) spin-weighted spherical harmonic modes. We also build a final black hole model, NRSur2dq1EccRemnant, which models the mass, and spin of the remnant black hole. We show that our waveform model can accurately predict numerical relativity waveforms with mismatches $\ensuremath{\approx}{10}^{\ensuremath{-}3}$, while the remnant model can recover the final mass and dimensionless spin with absolute errors smaller than…

We present numerical solutions of several spacetimes of physical interest, including binary black hole mergers, in shift-symmetric Einstein-scalar-Gauss-Bonnet (ESGB) gravity, and describe our methods for solving the full equations of motion, without approximation, for general spacetimes. While we concentrate on the specific example of shift-symmetric ESGB, our methods, which make use of a recently proposed modification to the generalized harmonic formulation, should be generally applicable to all Horndeski theories of gravity (including general relativity). We demonstrate that these methods can stably follow the formation of scalar clouds about initially vacuum nonspinning and spinning black holes for values of the Gauss-Bonnet coupling approaching the maximum value above which the hyperbolicity of the theory breaks down in spherical symmetry. We study the collision of black holes with scalar hair, finding that the theory remains hyperbolic in the spacetime region exterior to the black hole horizons in a similar regime, which includes cases where the deviations from general…

The experiment Neutrino-4 started in 2014 with a detector model and continued with a full-scale detector in 2016--2021. In this article, we describe all the steps of the preparatory work on this experiment. We present all results of the Neutrino-4 experiment with increased statistical accuracy provided to date. The experimental setup is constructed to measure the flux and spectrum of the reactor antineutrinos as a function of distance to the center of the active zone of the SM-3 reactor (Dimitrovgrad, Russia) in the range of 6--12 meters. Using all the collected data, we performed a model-independent analysis to determine the oscillation parameters $\mathrm{\ensuremath{\Delta}}{\mathrm{m}}_{14}^{2}$ and ${\mathrm{sin}}^{2}2{\ensuremath{\theta}}_{14}$. The method of coherent summation of measurement results allows us to directly demonstrate the oscillation effect. We present the analysis of possible systematic errors and the MC model of the experiment, which considers the possibility of the effect manifestation at the present precision level. As a result of the analysis, we can…

This paper studies the formation and growth of boson stars via gravitational condensation, using non-linear numerical techniques, incorporating, for the first time, fully dynamical repulsive and attractive self-interactions. For strong attraction, the boson star becomes unstable and ultimately breaks up for very strong coupling. Repulsion encourages boson star formation, whilst, in the case of pure gravity, the growth of boson stars in haloes slows down as per expectations.

We perform a comprehensive new Monte Carlo analysis of high-energy lepton-lepton, lepton-hadron and hadron-hadron scattering data to simultaneously determine parton distribution functions (PDFs) in the proton and parton to hadron fragmentation functions (FFs). The analysis includes all available semi-inclusive deep-inelastic scattering and single-inclusive ${e}^{+}{e}^{\ensuremath{-}}$ annihilation data for pions, kaons and unidentified charged hadrons, which allows the flavor dependence of the fragmentation functions to be constrained. Employing a new multistep fitting strategy and more flexible parametrizations for both PDFs and FFs, we assess the impact of different datasets on sea quark densities and confirm the previously observed suppression of the strange quark distribution. The new fit, which we refer to as ``JAM20-SIDIS,'' will allow for improved studies of universality of parton correlation functions, including transverse momentum dependent (TMD) distributions, across a wide variety of process, and the matching of collinear to TMD factorization descriptions.

The T2K experiment reports updated measurements of neutrino and antineutrino oscillations using both appearance and disappearance channels. This result comes from an exposure of $14.9(16.4)\ifmmode\times\else\texttimes\fi{}1{0}^{20}$ protons on target in neutrino (antineutrino) mode. Significant improvements have been made to the neutrino interaction model and far detector reconstruction. An extensive set of simulated data studies have also been performed to quantify the effect interaction model uncertainties have on the T2K oscillation parameter sensitivity. T2K performs multiple oscillation analyses that present both frequentist and Bayesian intervals for the Pontecorvo-Maki-Nakagawa-Sakata parameters. For fits including a constraint on ${\mathrm{sin}}^{2}{\ensuremath{\theta}}_{13}$ from reactor data and assuming normal mass ordering T2K measures ${\mathrm{sin}}^{2}{\ensuremath{\theta}}_{23}={0.53}_{\ensuremath{-}0.04}^{+0.03}$ and…

The recent release of the second Gravitational-Wave Transient Catalog (GWTC-2) has increased significantly the number of known GW events, enabling unprecedented constraints on formation models of compact binaries. One pressing question is to understand the fraction of binaries originating from different formation channels, such as isolated field formation versus dynamical formation in dense stellar clusters. In this paper, we combine the cosmic binary population synthesis suite and the cmc code for globular cluster evolution to create a mixture model for black hole binary formation under both formation scenarios. For the first time, these code bodies are combined self-consistently, with cmc itself employing cosmic to track stellar evolution. We then use a deep-learning enhanced hierarchical Bayesian analysis to continuously sample over and constrain the common envelope efficiency $\ensuremath{\alpha}$ assumed in cosmic, the initial cluster virial radius ${r}_{v}$ adopted in cmc, and the intrinsic mixture fraction $f$ between each channel. Under specific assumptions about other…

A Simpson-Visser spacetime has two non-negative parameters $a$ and $m$ and its metric is correspond with (i) a Schwarzschild metric for $a=0$ and $m\ensuremath{\ne}0$, (ii) a regular black hole metric for $a<2m$, (iii) a one-way traversable wormhole metric for $a=2m$, (vi) a two-way traversable wormhole metric for $a>2m$, and (v) an Ellis-Bronnikov wormhole metric for $a\ensuremath{\ne}0$ and $m=0$. The spacetime is one of the most useful spacetimes for the purpose of comprehensively understanding gravitational lensing of light rays reflected by a photon sphere of black holes and wormholes. We have investigated gravitational lensing in the Simpson-Visser spacetime in a strong deflection limit in all the non-negative parameters of $a$ and $m$. In a case of $a=3m$, two photon spheres and an antiphoton sphere at the throat degenerate into a marginally unstable photon sphere. The deflection angle of the light rays reflected by the marginally unstable photon sphere at the throat diverges nonlogarithmically in the strong deflection limit.

The distribution of effective spin ${\ensuremath{\chi}}_{\mathrm{eff}}$, a parameter that encodes the degree of spin-orbit alignment in a binary system, has been widely regarded as a robust discriminator between the isolated and dynamical formation pathways for merging binary black holes. Until the recent release of the GWTC-2 catalog, such tests have yielded inconclusive results due to the small number of events with measurable nonzero spins. In this work, we study the ${\ensuremath{\chi}}_{\mathrm{eff}}$ distribution of the binary black holes detected in the LIGO-Virgo O1--O3a observing runs. Our focus is on the degree to which the ${\ensuremath{\chi}}_{\mathrm{eff}}$ distribution is symmetric about ${\ensuremath{\chi}}_{\mathrm{eff}}=0$ and whether the data provide support for a population of negative-${\ensuremath{\chi}}_{\mathrm{eff}}$ systems. We find that the ${\ensuremath{\chi}}_{\mathrm{eff}}$ distribution is asymmetric at 95% credibility, with an excess of aligned-spin binary systems (${\ensuremath{\chi}}_{\mathrm{eff}}>0$) over antialigned ones. Moreover, we find that…

Recently, Barrow argued that quantum-gravitational effects may introduce intricate, fractal features on the black hole horizon [J. D. Barrow, , The area of a rough black hole, Phys. Lett. B 808, 135643 (2020)]. In this viewpoint, black hole entropy no longer obeys the area law and instead it can be given by $S\ensuremath{\sim}{A}^{1+\ensuremath{\delta}/2}$, where the exponent $\ensuremath{\delta}$ ranges $0\ensuremath{\le}\ensuremath{\delta}\ensuremath{\le}1$, and indicates the amount of the quantum-gravitational deformation effects. Based on this, and using the deep connection between gravity and thermodynamics, we disclose the effects of Barrow entropy on the cosmological equations. For this purpose, we start from the first law of thermodynamics, $dE=TdS+WdV$, on the apparent horizon of the Friedmann-Robertson-Walker universe, and derive the corresponding modified Friedmann equations by assuming that the entropy associated with the apparent horizon has the form of Barrow entropy. We also examine the validity of the generalized second law of thermodynamics for the Universe enclosed…

The linear-order effects of radiation-reaction on the classical scattering of two point masses, in general relativity, are derived by a variation-of-constants method. Explicit expressions for the radiation-reaction contributions to the changes of 4-momentum during scattering are given to linear order in the radiative losses of energy, linear-momentum, and angular momentum. The polynomial dependence on the masses of the 4-momentum changes is shown to lead to nontrivial identities relating the various radiative losses. At order ${G}^{3}$ our results lead to a streamlined classical derivation of results recently derived within a quantum approach. At order ${G}^{4}$ we compute the needed radiative losses to next-to-next-to-leading-order in the post-Newtonian expansion, thereby reaching the absolute fourth and a half post-Newtonian level of accuracy in the 4-momentum changes. We also provide explicit expressions, at the absolute sixth post-Newtonian accuracy, for the radiation-graviton contribution to conservative $O({G}^{4})$ scattering. At orders ${G}^{5}$ and ${G}^{6}$ we derive…

We consider the following question: may two different black holes (BHs) cast exactly the same shadow? In spherical symmetry, we show the necessary and sufficient condition for a static BH to be shadow-degenerate with Schwarzschild is that the dominant photonsphere of both has the same impact parameter, when corrected for the (potentially) different redshift of comparable observers in the different spacetimes. Such shadow-degenerate geometries are classified into two classes. The first shadow-equivalent class contains metrics whose constant (areal) radius hypersurfaces are isometric to those of the Schwarzschild geometry, which is illustrated by the Simpson and Visser (SV) metric. The second shadow-degenerate class contains spacetimes with different redshift profiles and an explicit family of metrics within this class is presented. In the stationary, axi-symmetric case, we determine a sufficient condition for the metric to be shadow degenerate with Kerr for far-away observers. Again we provide two classes of examples. The first class contains metrics whose constant…

We point out that there can be humanly traversable wormhole solutions in some previously considered theories for physics beyond the Standard Model, namely the Randall-Sundrum model.

Recent observations using the Atacama Cosmology Telescope (ACT) have provided ground-based cosmic microwave background (CMB) maps with higher angular resolution than the Planck satellite. These have the potential to put interesting constraints on models resolving the ``Hubble tension.'' In this paper we fit two models of early dark energy (EDE) (an increase in the expansion rate around matter/radiation equality) to the combination of ACT data with large-scale measurements of the CMB either from the WMAP or the Planck satellite (including lensing), along with measurements of the baryon acoustic oscillations and uncalibrated supernovae luminosity distance. We study a phenomenological axionlike potential (``axEDE'') and a scalar field experiencing a first-order phase transition (``NEDE''). We find that for both models the ``Planck-free'' analysis yields nonzero EDE at $\ensuremath{\gtrsim}2\ensuremath{\sigma}$ and an increased value for ${H}_{0}\ensuremath{\sim}70--74\text{ }\text{ }\mathrm{km}/\mathrm{s}/\mathrm{Mpc}$, compatible with local measurements, without the inclusion of any…

We report results from searches for anisotropic stochastic gravitational-wave backgrounds using data from the first three observing runs of the Advanced LIGO and Advanced Virgo detectors. For the first time, we include Virgo data in our analysis and run our search with a new efficient pipeline called pystoch on data folded over one sidereal day. We use gravitational-wave radiometry (broadband and narrow band) to produce sky maps of stochastic gravitational-wave backgrounds and to search for gravitational waves from point sources. A spherical harmonic decomposition method is employed to look for gravitational-wave emission from spatially-extended sources. Neither technique found evidence of gravitational-wave signals. Hence we derive 95% confidence-level upper limit sky maps on the gravitational-wave energy flux from broadband point sources, ranging from ${F}_{\ensuremath{\alpha},\mathrm{\ensuremath{\Theta}}}<(0.013--7.6)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}8}\text{ }\text{ }\mathrm{erg}\text{ }{\mathrm{cm}}^{\ensuremath{-}2}\text{…

We develop a flow-based sampling algorithm for $\mathrm{SU}(N)$ lattice gauge theories that is gauge invariant by construction. Our key contribution is constructing a class of flows on an $\mathrm{SU}(N)$ variable [or on a $\mathrm{U}(N)$ variable by a simple alternative] that respects matrix conjugation symmetry. We apply this technique to sample distributions of single $\mathrm{SU}(N)$ variables and to construct flow-based samplers for SU(2) and SU(3) lattice gauge theory in two dimensions.

In this paper we discuss the combination of the usual renormalization and factorization scale uncertainties of Higgs-pair production via gluon fusion with the novel uncertainties originating from the scheme and scale choice of the virtual top mass. Moreover, we address the uncertainties related to the top-mass definition for different values of the trilinear Higgs coupling and their combination with the other uncertainties.

Effective field theories describing gravity coupled to matter are investigated, allowing for operators of arbitrary mass dimension. Terms violating local Lorentz and diffeomorphism invariance while preserving internal gauge symmetries are included. The theoretical framework for violations of local Lorentz and diffeomorphism invariance and associated conceptual issues are discussed, including transformations in curved and approximately flat spacetimes, the treatment of various types of backgrounds, the implications of symmetry breaking, and the no-go constraints for explicit violation in Riemann geometry. Techniques are presented for the construction of effective operators, and the possible terms in the gravity, gauge, fermion, and scalar sectors are classified and enumerated. Explicit expressions are obtained for terms containing operators of mass dimension six or less in the effective action for general relativity coupled to the Standard Model of particle physics. Special cases considered include Einstein-Maxwell effective field theories and the limit with only scalar coupling…

The mass radius is a fundamental property of the proton that so far has not been determined from experiment. Here, we show that the mass radius of the proton can be rigorously defined through the form factor of the trace of the energy-momentum tensor (EMT) of QCD in the weak gravitational field approximation, as appropriate for this problem. We then demonstrate that the scale anomaly of QCD enables the extraction of the form factor of the trace of the EMT from the data on threshold photoproduction of $J/\ensuremath{\psi}$ and $\mathrm{\ensuremath{\Upsilon}}$ quarkonia, and use the recent GlueX Collaboration data to extract the rms mass radius of the proton ${\mathrm{R}}_{\mathrm{m}}=0.55\ifmmode\pm\else\textpm\fi{}0.03\text{ }\text{ }\mathrm{fm}$. The extracted mass radius is significantly smaller than the rms charge radius of the proton ${\mathrm{R}}_{\mathrm{c}}=0.8409\ifmmode\pm\else\textpm\fi{}0.0004\text{ }\text{ }\mathrm{fm}$. We attribute this difference to the interplay of asymptotic freedom and spontaneous breaking of chiral symmetry in QCD, and outline future measurements…

Primordial black holes (PBHs), formed out of large overdensities in the early Universe, are a viable dark matter (DM) candidate over a broad range of masses. Ultralight, asteroid-mass PBHs with masses around ${10}^{17}\text{ }\text{ }\mathrm{g}$ are particularly interesting as current observations allow them to constitute the entire DM density. PBHs in this mass range emit $\ensuremath{\sim}\mathrm{MeV}$ photons via Hawking radiation which can directly be detected by the gamma ray telescopes, such as the upcoming AMEGO. In this work we forecast how well an instrument with the sensitivity of AMEGO will be able to detect, or rule out, PBHs as a DM candidate, by searching for their evaporating signature when marginalizing over the Galactic and extra-Galactic gamma-ray backgrounds. We find that an instrument with the sensitivity of AMEGO could exclude nonrotating PBHs as the only DM component for masses up to $7\ifmmode\times\else\texttimes\fi{}{10}^{17}\text{ }\text{ }\mathrm{g}$ at 95% confidence level for a monochromatic mass distribution, improving upon current bounds by nearly an…