We discuss the nonlinear corrections entering in the calculation of the primordial black hole abundance from the nonlinear radiation transfer function and the determination of the true physical horizon crossing. We show that the current standard techniques to calculate the abundance of primordial black holes suffer from uncertainties and argue that the primordial black hole abundance may be much smaller than what routinely considered. This would imply, among other consequences, that the interpretation of the recent pulsar timing arrays data from scalar-induced gravitational waves may not be ruled out because of an overproduction of primordial black holes.

We calculate the effect of gravitational lensing on the parity-odd power spectrum of the cosmic microwave background (CMB) polarization induced by axionlike particles (ALPs). Several recent works have reported a tantalizing hint of cosmic birefringence, a rotation of the linear polarization plane of CMB, which ALPs can explain. In future CMB observations, we can measure cosmic birefringence more precisely to get insight into ALPs. We find that the lensing effect is necessary to fit the observed $EB$ power spectrum induced by cosmic birefringence in future CMB observations, including Simons Observatory and CMB-S4. We also show that the estimated ALPs parameters are biased if we ignore the lensing effect. Therefore, the lensing correction to the parity-odd power spectra must be included in future high-resolution CMB experiments.

This article provides the details on the technical derivation of the gravitational waveform and total gravitational-wave energy flux of nonspinning compact binary systems to the fourth post-Newtonian (4PN) order beyond the Einstein quadrupole formula. In particular: (i) we overview the link between the radiative multipole moments measured at infinity and the source moments in the framework of dimensional regularization; (ii) we compute special corrections to the source moments due to “infrared” commutators arising at the 4PN order; (iii) we derive a “postadiabatic” correction needed to evaluate the tail integral with 2.5PN relative precision; (iv) we discuss the relation between the binary’s orbital frequency in quasicircular orbit and the gravitational-wave frequency measured at infinity; (v) we compute the hereditary effects at the 4PN order, including those coming from the recently derived tails-of-memory; and (vi) we describe the various tests we have performed to ensure the correctness of the results. Those results are collected in an ancillary file.

We present evidence for a duality between Jackiw-Teitelboim gravity minimally coupled to a free massive scalar field and a single-trace two-matrix model. One matrix is the Hamiltonian $H$ of a holographic disorder-averaged quantum mechanics, while the other matrix is the light operator $\mathcal{O}$ dual to the bulk scalar field. The single-boundary observables of interest are thermal correlation functions of $\mathcal{O}$. We study the matching of the genus zero-, one- and two-boundary expectation values in the matrix model to the disk and cylinder Euclidean path integrals. The non-Gaussian statistics of the matrix elements of $\mathcal{O}$ correspond to a generalization of the eigenstate thermalization hypothesis ansatz. We describe multiple ways to construct double-scaled matrix models that reproduce the gravitational disk correlators. One method involves imposing an operator equation obeyed by $H$ and $\mathcal{O}$ as a constraint on the two matrices. Separately, we design a model that reproduces certain double-scaled Sachdev-Ye-Kitaev correlators that may be scaled once more to obtain the disk correlators. We show that in any single-trace, two-matrix model, the genus zero two-boundary expectation value, with up to one $\mathcal{O}$ insertion on each boundary, can be computed directly from all of the genus zero one-boundary correlators. Applied to the models of interest, we find that these cylinder observables depend on the details of the double-scaling limit. To the extent we have checked, it is possible to reproduce the gravitational double-trumpet, which is UV divergent, from a systematic classification of matrix model ‘t Hooft diagrams. The UV divergence indicates that the matrix integral saddle of interest is perturbatively unstable. A nonperturbative treatment of the matrix models discussed in this work is left for future investigations.

New light scalar degrees of freedom may alleviate the dark matter and dark energy problems, but if coupled to matter, they generally mediate a fifth force. In order for this fifth force to be consistent with existing constraints, it must be suppressed close to matter sources, e.g. through a nonlinear screening mechanism. In this work, we investigate the nonrelativistic two-body problem in shift-symmetric scalar-tensor theories that exhibit kinetic screening ($k$ mouflage), both numerically and analytically. We develop an approximate scheme, based on a Hodge-Helmholtz decomposition of the Noether current associated to the shift symmetry, allowing for a qualitative insight into the dynamics and yielding results in good agreement with the numerical ones in most of the parameter space. We apply the formalism to polynomial $k$ essence and to Dirac-Born-Infeld type theories, as well as to theories that develop “anti-screening.” In the deep nonlinear regime, we find that the fifth force is screened slightly more efficiently in equal-mass systems than in extreme mass-ratio ones. However, we find that systems with comparable masses also exhibit regions where the screening is ineffective. These descreened spheroidal regions (bubbles) could in principle be probed in the Solar System with sufficiently precise space accelerometers.

We develop a frequency-domain method for calculating the self-force acting on a scalar charge on a fixed scattering geodesic in Schwarzschild spacetime. Existing frequency-domain methods, which are tailored for bound orbits, are inadequate here for several reasons. One must account for the continuous spectrum in the scattering problem, deal with slowly convergent radial integrals that are hard to evaluate numerically, and confront the inapplicability of the standard self-force method of “extended homogeneous solutions,” which only works for compactly supported sources. We tackle each of these issues in turn, and then present a full numerical implementation, in which we calculate the self-force correction to the scatter angle due to scalar-field backreaction. We perform a range of internal validation tests, as well as ones based on comparison with existing time-domain results. We discuss the merits and remaining limitations of our method, and outline directions for future work.

The physical interpretation of the exact solutions of the Einstein field equations is, in general, a challenging task, part of the difficulties lying in the significance of the coordinate system. We discuss the extension of the International Astronomical Union (IAU) reference system to the exact theory. It is seen that such an extension, retaining some of its crucial properties, can be achieved in a special class of spacetimes, admitting nonshearing congruences of observers which, at infinity, have zero vorticity and acceleration. As applications, we consider the Friedmann–Lemaître–Robertson–Walker (FLRW), Kerr and Newman–Unti–Tamburino (NUT) spacetimes, the van Stockum rotating dust cylinder, spinning cosmic strings and, finally, we debunk the so-called Balasin-Grumiller (BG) model, and the claims that the galaxies’ rotation curves can be explained through gravitomagnetic effects without the need for dark matter. The BG spacetime is shown to be completely inappropriate as a galactic model: its dust is actually static with respect to the asymptotic inertial frame, its gravitomagnetic effects arise from unphysical singularities along the axis (a pair of NUT rods, combined with a spinning cosmic string), and the rotation curves obtained are merely down to an invalid choice of reference frame—the congruence of zero angular momentum observers, which are being dragged by the singularities.

The $J/\psi \to {\mathrm{\Xi }}^0{\overline{\mathrm{\Xi }}}^0$ process and subsequent decays are investigated using $(10087\pm 44)\times {10}^{6}J/\psi$ events collected at the BESIII experiment. The decay parameters of ${\mathrm{\Xi }}^0$ and ${\overline{\mathrm{\Xi }}}^0$ are simultaneously measured to be ${\alpha }_{\mathrm{\Xi }}=-0.3750\pm 0.0034\pm 0.0016$, ${\overline{\alpha }}_{\mathrm{\Xi }}=0.3790\pm 0.0034\pm 0.0021$, ${\varphi }_{\mathrm{\Xi }}=0.0051\pm 0.0096\pm 0.0018\mathrm{rad}$, ${\overline{\varphi }}_{\mathrm{\Xi }}=-0.0053\pm 0.0097\pm 0.0019\mathrm{rad}$ with unprecedented accuracies, where the first and the second uncertainties are statistical and systematic, respectively. The most precise values for $CP$ asymmetry observables of ${\mathrm{\Xi }}^0$ decay are obtained to be $A_{CP}^{\mathrm{\Xi }}=(-5.4\pm 6.5\pm 3.1)\times {10}^{-3}$ and $\mathrm{\Delta }{\varphi }_{CP}^{\mathrm{\Xi }}=(-0.1\pm 6.9\pm 0.9)\times {10}^{-3}\mathrm{rad}$. For the first time, the weak and strong phase differences are determined to be ${\xi }_P-{\xi }_S=(0.0\pm 1.7\pm 0.2)\times {10}^{-2}\mathrm{rad}$ and ${\delta }_P-{\delta }_S=(-1.3\pm 1.7\pm 0.4)\times {10}^{-2}\mathrm{rad}$, which are the most precise results for any weakly decaying baryon. These results will play important roles in the studies of the $CP$ violations and polarizations for the strange, charmed, and beauty baryons.

We discuss the structure of nonlocal effective action generating the conformal anomaly in classically Weyl invariant theories in curved spacetime. By the procedure of conformal gauge fixing, selecting the metric representative on a conformal group orbit, we split the renormalized effective action into anomalous and Weyl invariant parts. A wide family of thus obtained anomalous actions is shown to include two special cases of Riegert–Fradkin–Tseytlin and Fradkin–Vilkovisky actions. Both actions are shown to be contained in the first 3 orders of the curvature expansion for a generic one-loop effective action obtained by covariant perturbation theory. The complementary Weyl invariant part of the action is given by the “conformization” of the full effective action—restricting its argument to the conformally invariant representative of the orbit of the conformal group. This is likely to resolve a long-standing debate between the proponents of the Riegert action and adherents of the perturbation expansion for the effective action with typical nonlocal logarithmic form factors. We derive the relation between quantum stress tensors on conformally related metric backgrounds, which generalizes the known Brown-Cassidy equation to the case of nonzero Weyl tensor, and discuss applications of this relation in the cosmological model driven by conformal field theory. We also discuss the issue of renormalization group running for the cosmological and gravitational coupling constants and show that it exhibits a kind of a metamorphosis to the nonlocal form factors of the so-called partners of the cosmological and Einstein terms—nonlocal curvature squared terms of the effective action.

We study the effect of super-sample covariance (SSC) on the power spectrum and higher-order statistics; bispectrum, halo mass function, and void size function. We also investigate the effect of SSC on the cross covariance between the statistics. We consider both the matter and halo fields. Higher-order statistics of the large-scale structure contain additional cosmological information beyond the power spectrum and are a powerful tool to constrain cosmology. They are a promising probe for ongoing and upcoming high-precision cosmological surveys such as DESI, PFS, Rubin Observatory LSST, Euclid, SPHEREx, SKA, and Roman Space Telescope. Cosmological simulations used in modeling and validating these statistics often have sizes that are much smaller than the observed Universe. Density fluctuations on scales larger than the simulation box, known as super-sample modes, are not captured by the simulations and in turn can lead to inaccuracies in the covariance matrix. We compare the covariance measured using simulation boxes containing super-sample modes to those without. We also compare with the separate universe approach. We find that while the power spectrum, bispectrum and halo mass function show significant scale- or mass-dependent SSC, the void size function shows relatively small SSC. We also find significant SSC contributions to the cross covariances between the different statistics, implying that future joint analyses will need to carefully take into consideration the effect of SSC. To enable further study of SSC, our simulations have been made publicly available.

The study of impulsive astrophysical radio emission makes it possible to probe the intervening plasma between the emission source and the Earth. In cold electron-ion plasmas, the circular propagating wave modes primarily alter the linear polarization plane that scales with the inverse-square of the emission frequency. In relativistic plasmas, the wave modes are elliptically polarized, and it is possible to convert linearly polarized emission into circular and vice versa. Fast radio bursts (FRBs) enable the study of not only the electron-ion plasma of the intergalactic medium but potentially the extreme magneto-ionic medium in which these intense pulses are produced. Here we report on the polarimetric analysis of a repeat burst from the FRB 20201124A source. The burst displayed a significant frequency-dependent circularly polarized component, unlike other bursts from this source or any other FRB found to date. We model the frequency dependence of the circular polarization using a phenomenological generalized Faraday rotation framework. We find that the observed circular polarization in the burst can be adequately explained by the propagation of an initially linearly polarized burst signal through a relativistic plasma along the line of sight from the progenitor.

The $B^{+}\to D_s^{+}{D}_s^{-}{K}^{+}$ decay is observed for the first time using proton-proton collision data collected by the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV, corresponding to an integrated luminosity of $9{\mathrm{fb}}^{-1}$. Its branching fraction relative to that of the $B^{+}\to D^{+}{D}^{-}{K}^{+}$ decay is measured to be $\frac{\mathcal{B}(B^{+}\to D_s^{+}{D}_s^{-}{K}^{+})}{\mathcal{B}(B^{+}\to D^{+}{D}^{-}{K}^{+})}=0.525\pm 0.033\pm 0.027\pm 0.034,$ where the first uncertainty is statistical, the second systematic, and the third is due to the uncertainties on the branching fractions of the $D_s^{\pm }\to K^{\mp }{K}^{\pm }{\pi }^{\pm }$ and $D^{\pm }\to K^{\mp }{\pi }^{\pm }{\pi }^{\pm }$ decays. This measurement fills an experimental gap in the knowledge of the family of Cabibbo-favored $\overline{b}\to \overline{c}c\overline{s}$ transitions and opens the path for unique studies of spectroscopy in future.

A simultaneous analysis of the $B^{+}\to K^{+}{\ell }^{+}{\ell }^{-}$ and $B^0\to K^{*0}{\ell }^{+}{\ell }^{-}$ decays is performed to test muon-electron universality in two ranges of the square of the dilepton invariant mass, $q^2$. The measurement uses a sample of beauty meson decays produced in proton-proton collisions collected with the LHCb detector between 2011 and 2018, corresponding to an integrated luminosity of $9{\mathrm{fb}}^{-1}$. A sequence of multivariate selections and strict particle identification requirements produce a higher signal purity and a better statistical sensitivity per unit luminosity than previous LHCb lepton universality tests using the same decay modes. Residual backgrounds due to misidentified hadronic decays are studied using data and included in the fit model. Each of the four lepton universality measurements reported is either the first in the given $q^2$ interval or supersedes previous LHCb measurements. The results are compatible with the predictions of the Standard Model.

Resonant contributions in $B^0\to \overline{D}{{}^{0}D}_s^{+}{\pi }^{-}$ and $B^{+}\to D^{-}{D}_s^{+}{\pi }^{+}$ decays are determined with an amplitude analysis, which is performed both separately and simultaneously, where in the latter case isospin symmetry between the decays is assumed. The analysis is based on data collected by the LHCb detector in proton-proton collisions at center-of-mass energies of 7, 8, and 13 TeV. The full data sample corresponds to an integrated luminosity of $9{\mathrm{fb}}^{-1}$. A doubly charged spin-0 open-charm tetraquark candidate together with a neutral partner, both with masses near 2.9 GeV, are observed in the $D_s\pi$ decay channel.

The kinematic and thermal Sunyaev-Zel’dovich (kSZ and tSZ) effects probe the abundance and thermodynamics of ionized gas in galaxies and clusters. We present a new hybrid estimator to measure the kSZ effect by combining cosmic microwave background temperature anisotropy maps with photometric and spectroscopic optical survey data. The method interpolates a velocity reconstruction from a spectroscopic catalog at the positions of objects in a photometric catalog, which makes it possible to leverage the high number density of the photometric catalog and the precision of the spectroscopic survey. Combining this hybrid kSZ estimator with a measurement of the tSZ effect simultaneously constrains the density and temperature of free electrons in the photometrically selected galaxies. Using the $1000{\mathrm{deg}}^2$ of overlap between the Atacama Cosmology Telescope (ACT) Data Release 5, the first three years of data from the Dark Energy Survey (DES), and the Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 12, we detect the kSZ signal at $4.8\sigma$ and reject the null (no-kSZ) hypothesis at $5.1\sigma$. This corresponds to $2.0\sigma$ per 100,000 photometric objects with a velocity field based on a spectroscopic survey with $1/5^{\mathrm{th}}$ the density of the photometric catalog. For comparison, a recent ACT analysis using exclusively spectroscopic data from BOSS measured the kSZ signal at $2.1\sigma$ per 100,000 objects. Our derived constraints on the thermodynamic properties of the galaxy halos are consistent with previous measurements. With future surveys, such as the Dark Energy Spectroscopic Instrument and the Rubin Observatory Legacy Survey of Space and Time, we expect that this hybrid estimator could result in measurements with significantly better signal-to-noise than those that rely on spectroscopic data alone.

We present a sample-variance-limited measurement of the temperature power spectrum ($TT$) of the cosmic microwave background using observations of a $\sim 1500{\mathrm{deg}}^2$ field made by the SPT-3G in 2018. We report multifrequency power spectrum measurements at 95, 150, and 220 GHz covering the angular multipole range $750\le \ell <3000$. We combine this $TT$ measurement with the published polarization power spectrum measurements from the 2018 observing season and update their associated covariance matrix to complete the SPT-3G 2018 $TT/TE/EE$ dataset. This is the first analysis to present cosmological constraints from SPT $TT$, $TE$, and $EE$ power spectrum measurements jointly. We blind the cosmological results and subject the dataset to a series of consistency tests at the power spectrum and parameter level. We find excellent agreement between frequencies and spectrum types and our results are robust to the modeling of astrophysical foregrounds. We report results for $\mathrm{\Lambda }\mathrm{CDM}$ and a series of extensions, drawing on the following parameters: the amplitude of the gravitational lensing effect on primary power spectra $A_{\mathrm{L}}$, the effective number of neutrino species $N_{\mathrm{eff}}$, the primordial helium abundance $Y_{\mathrm{P}}$, and the baryon clumping factor due to primordial magnetic fields $b$. We find that the SPT-3G 2018 $TT/TE/EE$ data are well fit by $\mathrm{\Lambda }\mathrm{CDM}$ with a probability to exceed of 15%. For $\mathrm{\Lambda }\mathrm{CDM}$, we constrain the expansion rate today to $H_0=68.3\pm 1.5\mathrm{km}{\mathrm{s}}^{-1}{\mathrm{Mpc}}^{-1}$ and the combined structure growth parameter to $S_8=0.797\pm 0.042$. The SPT-based results are effectively independent of Planck, and the cosmological parameter constraints from either dataset are within $<1\sigma$ of each other. The addition of temperature data to the SPT-3G $TE/EE$ power spectra improves constraints by 8–27% for each of the $\mathrm{\Lambda }\mathrm{CDM}$ cosmological parameters. When additionally fitting $A_{\mathrm{L}}$, $N_{\mathrm{eff}}$, or $N_{\mathrm{eff}}+Y_{\mathrm{P}}$, the posteriors of these parameters tighten by 5–24%. In the case of primordial magnetic fields, complete $TT/TE/EE$ power spectrum measurements are necessary to break the degeneracy between $b$ and $n_s$, the spectral index of primordial density perturbations. We report a 95% confidence upper limit from SPT-3G data of $b<1.0$. The cosmological constraints in this work are the tightest from SPT primary power spectrum measurements to date and the analysis forms a new framework for future SPT analyses.

We calculate shear viscosity and bulk viscosity in $SU(3)$ gauge theory on the lattice at $1.5T_c$. The viscosities are extracted via a Kubo formula from the reconstructed spectral function which we determine from the Euclidean time dependence of the corresponding channel of the energy-momentum tensor correlators. We obtain unprecedented precision for the correlators by applying gradient-flow and blocking methods. The correlators are extrapolated to the continuum and then to zero-flow time. To extract the viscosities we fit theoretically inspired models to the lattice data and cross-check the fit results using the Backus-Gilbert method. The final estimates for shear and bulk viscosity are $\eta /s=0.15–0.48$ and $\zeta /s=0.017–0.059$.

Using standard mathematical methods for asymptotic series and the large-${\beta }_0$ approximation, we define a minimum distance between the fixed-order perturbative series and the contour-improved perturbative series in the strong coupling ${\alpha }_s$ for finite-energy sum rules as applied to hadronic $\tau$ decays. This distance is similar, but not identical, to the asymptotic separation of Hoang and Regner, which is defined in terms of the difference of the two series after Borel resummation. Our results confirm a nonzero nonperturbative result in ${\alpha }_s$ for this minimum distance as a measure of the intrinsic difference between the two series, as well as a conflict with the operator product expansion for contour-improved perturbation theory.

We establish that Polchinski’s equation for exact renormalization group (RG) flow is equivalent to the optimal transport gradient flow of a field-theoretic relative entropy. This provides a compelling information-theoretic formulation of the exact renormalization group, expressed in the language of optimal transport. A striking consequence is that a regularization of the relative entropy is in fact an RG monotone. We compute this monotone in several examples. Our results apply more broadly to other exact renormalization group flow equations, including widely used specializations of Wegner-Morris flow. Moreover, our optimal transport framework for RG allows us to reformulate RG flow as a variational problem. This enables new numerical techniques and establishes a systematic connection between neural network methods and RG flows of conventional field theories.

Gravity in $4d$ asymptotically flat spacetime constitutes the archetypal example of a gravitational system with leaky boundary conditions. Pursuing our previous analysis of [Carrollian Perspective on Celestial Holography, Phys. Rev. Lett. 129, 071602 (2022)], we argue that the holographic description of such a system requires the coupling of the dual theory living at null infinity to some external sources encoding the radiation reaching the conformal boundary and responsible for the nonconservation of the charges. In particular, we show that the sourced Ward identities of a conformal Carrollian field theory living at null infinity reproduce the Bondi-van der Burg-Metzner-Sachs flux-balance laws. We also derive the general form of low-point correlation functions for conformal Carrollian field theories and exhibit a new branch of solutions, which is argued to be the relevant one for holographic purposes. We then relate our Carrollian approach to the celestial holography proposal by mapping the Carrollian Ward identities to those constraining celestial operators through a suitable integral transform.