When gravitational waves pass near a gravitating object, they are deflected, or lensed. If the object is massive, such that the wavelength of the waves is small compared to its gravitational size, lensed gravitational wave events can be identified when multiple signals are detected at different times. However, when the wavelength is long, wave-optics diffraction effects will be important, and a lensed event can be identified by looking for frequency-dependent modulations to the gravitational waveform, without having to associate multiple signals. For current ground-based gravitational wave detectors observing stellar-mass binary compact object mergers, wave-optics effects are important for lenses with masses $\lesssim 1000M_{\odot }$. Therefore, minihalos below this mass range could potentially be identified by lensing diffraction. The challenge with analyzing these events is that the frequency-dependent lensing modulation, or the amplification factor, is prohibitively expensive to compute for Bayesian parameter inference. In this work, we use a novel time-domain method to construct interpolators of the amplification factor for the Navarro-Frenk-White, generalized singular isothermal sphere and cored isothermal sphere lens models. Using these interpolators, we perform Bayesian inference on gravitational wave signals lensed by minihalos injected in mock detector noise, assuming current sensitivity of ground-based detectors. We find that we could potentially identify an event when it is lensed by minihalos and extract the values of all lens parameters in addition to the parameters of the GW source. All of the methods are implemented in glworia [1], the accompanying open-source python package, and can be generalized to study lensed signals detected by current and next-generation detectors.

We calculate the cosmic microwave background $B$-mode power spectrum resulting from anisotropic cosmic birefringence, without relying on the thin approximation of the last scattering surface. Specifically, we consider the influence of anisotropic cosmic birefringence arising from massless axionlike particles. Comparing our results to those obtained using the thin approximation, we observe a suppression in the amplitude of the $B$-mode power spectrum by approximately an order of magnitude at large angular scales ($\ell \lesssim 10$) and by a factor of 2 at small angular scales ($\ell \gtrsim 100$) when not employing the thin approximation. We also constrain the amplitude of the angular power spectrum of the scale-invariant anisotropic cosmic birefringence using the SPTpol $B$-mode power spectrum. We find that the amplitude is constrained as $A_{\mathrm{CB}}\times {10}^4={1.03}_{-0.97}^{+0.91}(2\sigma )$.

Starting with the density field equation of a self-gravity fluid in a static Universe, using the Schwinger functional differentiation technique, we derive the field equation of the 4-point correlation function (4PCF) of galaxies in the Gaussian approximation, which contains hierarchically 2PCF and 3PCF. By use of the known solutions of 2PCF and 3PCF, the equation of 4PCF becomes an inhomogeneous, Helmholtz equation, and contains only two physical parameters: the mass $m$ of galaxy and the Jeans wave number $k_J$, like the equations of the 2PCF and 3PCF. We obtain the analytical solution of 4PCF that consists of four portions, $\eta ={\eta }_{\text{odd}}^0+{\eta }_{\text{even}}^0+{\eta }^{\mathrm{FP}}+{\eta }^I$, and has a very rich structure. ${\eta }_{\text{odd}}^0$ and ${\eta }_{\text{even}}^0$ form the homogeneous solution and depend on boundary conditions. The parity-odd ${\eta }_{\text{odd}}^0$ is more interesting and qualitatively explains the observed parity-odd data of BOSS CMASS, the parity-even ${\eta }_{\text{even}}^0$ contains the disconnected 4PCF ${\eta }^{\mathrm{disc}}$ (arising from a Gaussian random process), and both ${\eta }_{\text{odd}}^0$ and ${\eta }_{\text{even}}^0$ are prominent at large scales $r\gtrsim 10\mathrm{Mpc}$, and exhibit radial oscillations determined by the Jeans wave number. ${\eta }^{\mathrm{FP}}$ and ${\eta }^I$ are parity even, and form the inhomogeneous solution. ${\eta }^{\mathrm{FP}}$ is the same as the Fry-Peebles ansatz for 4PCF, and dominates at small scales $r\lesssim 10\mathrm{Mpc}$. ${\eta }^I$ is an integration of the inhomogeneous term, subdominant. We also compare the parity-even 4PCF with the observation data.

This paper simplifies the induced four-dimensional gravitational equations originating from a five-dimensional bulk within the framework of Nash’s embeddings, incorporating them into a well-known $\mu -\mathrm{\Sigma }$ modified gravity parametrization. By leveraging data from Planck Public Release 4, BICEP/Keck Array 2018, Planck cosmic microwave background lensing, and baryon acoustic oscillation observations, we establish a stringent lower limit for the tensor-to-scalar ratio parameter: $r<0.0303$ at a confidence level (CL) of 95%. This finding suggests the presence of extrinsic dynamics influencing standard four-dimensional cosmology. Notably, this limit surpasses those typically obtained through Bayesian analysis using Markov chain Monte Carlo techniques, which yield $r<0.038$, or through the frequentist profile likelihood method, which yields $r<0.037$ at 95% CL.

Cosmologies in which dark matter clumps strongly on small scales are unfavorable to terrestrial detectors that are as yet unexposed to the clumps. I show that subhectometer clumps could trigger thermonuclear runaways by scattering on nuclei in white dwarf cores (carbon and oxygen) and neutron star oceans (carbon), setting off type-Ia-like supernovae and x-ray superbursts, respectively. I consider two scenarios: “dark clusters” that are essentially microhalos and “long-range dark nuggets,” essentially macroscopic composites, with long-range Yukawa baryonic interactions that source the energy for igniting explosions. I constrain dark clusters, weighing between the Planck mass and asteroid masses, and long-range dark nuggets over a wider mass range spanning 40 orders of magnitude. These limits greatly complement searches proposed by myself and co-workers [Phys. Rev. Lett. 128, 231801 (2022)] for scattering interactions of dark clumps in neutron stars, cosmic rays, and prehistoric minerals.

Relativistic plasmas around compact objects can sometimes be approximated as being force-free. In this limit, the plasma inertia is negligible and the overall dynamics is governed by global electric currents. We present a novel numerical approach for simulating such force-free plasmas, which allows for high accuracy in smooth regions as well as capturing dissipation in current sheets. Using a high-order accurate discontinuous Galerkin method augmented with a conservative finite-difference method, we demonstrate efficient global simulations of black hole and neutron star magnetospheres. In addition to a series of challenging test problems, we show that our approach can—depending on the physical properties of the system and the numerical implementation—be up to $10\times$ more efficient than conventional simulations, with a speedup of $2–3\times$ for most problems we consider in practice.

Recent observations of the high-redshift universe have uncovered a significant number of active galactic nuclei, implying that supermassive black holes (SMBHs) would have to have been formed at much earlier times than expected. Direct collapse of metal-free gas clouds to SMBHs after recombination could help explain the early formation of SMBHs, but this scenario is stymied by the fragmentation of the clouds due to efficient molecular hydrogen cooling. We show that a subdominant population of tiny, evaporating primordial black holes, with significant clustering in some gas clouds, can heat the gas sufficiently so that molecular hydrogen is not formed, and direct collapse to black holes is possible even at high redshifts.

Binary pulsars can be used to probe Galactic potential gradients through calculating their line-of-sight accelerations. We present the first data release of direct line-of-sight acceleration measurements for 29 binary pulsars. We validate these data with a local acceleration model, and compare our results to those from earlier works. We find evidence for an acceleration gradient in agreement with these values, with our results indicating a local disk density of ${\rho }_{\mathrm{d}}={\mathrm{0.040}}_{-\mathrm{0.020}}^{+\mathrm{0.020}}{M}_{\odot }{\mathrm{pc}}^{-3}$. We also find evidence for unmodeled noise of unknown origin in our dataset.

Very recently, the Belle II collaboration presented a measurement for the decays $B^{+}\to {\overline{D}}^{(*)0}{K}^{+}{\overline{K}}^0$ and $B^0\to D^{(*)-}{K}^{+}{\overline{K}}^0$, with the bulk of observed $m(K^{+}{K}_S^0)$ distributions showing low-mass structures in all four channels. In this work, we study the contributions of $\rho (770,1450{)}^{+}$, $a_2(1320{)}^{+}$, and $a_0(980,1450{)}^{+}$ resonances to these decay processes. The intermediate states $\rho (770,1450{)}^{+}$ are found to dominate the low-mass distribution of kaon pairs roughly contributing to half of the total branching fraction in each of the four decay channels. The contribution of the tensor $a_2(1320{)}^{+}$ meson is found to be negligible. Near the threshold of the kaon pair, the state $a_0(980{)}^{+}$ turns out to be much less important than expected, not being able to account for the enhancement of events in that energy region observed in the $B^{+}\to {\overline{D}}^{(*)0}{K}^{+}{\overline{K}}^0$ decays. Further studies both from the theoretical and experimental sides are needed to elucidate the role of the nonresonant contributions governing the formation of $K^{+}{\overline{K}}^0$ pairs near their threshold in these decay processes.

We obtain the spatial and momentum-diffusion coefficients ($D_s$ and $\kappa$) and the collisional energy loss ($dE/dx$) of a heavy quark (HQ) traversing through a thermal medium of quarks and gluons in a weak magnetic field ($B$), for the two cases of the HQ moving either parallel or perpendicular to $\mathit{B}$. For that purpose, we consider Coulomb scatterings ($t$-channel) of the HQ with the light quarks, obtained from the imaginary part of the HQ self-energy via the cutting rules. Both the normalized (by $T^3$) $\kappa$, and $dE/dx$, for charm quarks are larger than that for bottom quarks due to the larger mass of the latter. Also, the effect of $B$ is more feeble on the bottom quark, compared to the charm quark. Comparatively, the magnitudes of both $\kappa$ and $dE/dx$ are significantly smaller for the case of $\mathit{v}\perp \mathit{B}$. For both the cases, our results show that the momentum transfer between the HQ and the medium takes place preferentially along the direction of HQ velocity, thus leading to a significant increase in the momentum-diffusion anisotropy, compared to $B=0$. We also calculate the (scaled) spatial diffusion coefficient, which we find to be independent of the heavy flavor mass and is almost unaffected by changes in $B$.

Quantum tomography has become an indispensable tool in order to compute the density matrix $\rho$ of quantum systems in physics. Recently, it has further gained importance as a basic step to test entanglement and violation of Bell inequalities in high-energy particle physics. In this work, we present the theoretical framework for reconstructing the helicity quantum initial state of a general scattering process. In particular, we perform an expansion of $\rho$ over the irreducible tensor operators $\{T_M^L\}$ and compute the corresponding coefficients uniquely by averaging, under properly chosen Wigner D-matrices weights, the angular distribution data of the final particles. Besides, we provide the explicit angular dependence of a novel generalization of the production matrix $\mathrm{\Gamma }$ and of the normalized differential cross section of the scattering. Finally, we rederive all our previous results from a quantum-information perspective using the Weyl-Wigner-Moyal formalism and we obtain, in addition, simple analytical expressions for the Wigner $P$ and $Q$ symbols.

In this work, an unquenched quark model is proposed for describing the heavy-light mesons by taking into account the coupled-channel effects induced by chiral dynamics. After including a relativistic correction term for the strong transition amplitudes, both the mass spectra and decay widths of the observed heavy-light mesons can be successfully described simultaneously in a unified framework, several long-standing puzzles related to the small masses and broad widths are overcome naturally. We also provide valuable guidance in searching new heavy-light mesons by the detailed predictions of their masses, widths, and branching ratios. The success of the unquenched quark model presented in this work indicates it may be an important step for understanding the hadron spectrum.

Hadron wave packets are prepared and time evolved in the Schwinger model using 112 qubits of IBM’s 133-qubit Heron quantum computer ibm_torino. The initialization of the hadron wave packet is performed in two steps. First, the vacuum is prepared across the whole lattice using the recently developed SC-ADAPT-VQE algorithm and workflow. SC-ADAPT-VQE is then extended to the preparation of localized states, and used to establish a hadron wave packet on top of the vacuum. This is done by adaptively constructing low-depth circuits that maximize the overlap with an adiabatically prepared hadron wave packet. Due to the localized nature of the wavepacket, these circuits can be determined on a sequence of small lattices using classical computers, and then robustly scaled to prepare wave packets on large lattices for simulations using quantum computers. Time evolution is implemented with a second-order Trotterization. To reduce both the required qubit connectivity and circuit depth, an approximate quasilocal interaction is introduced. This approximation is made possible by the emergence of confinement at long distances, and converges exponentially with increasing distance of the interactions. Using multiple error-mitigation strategies, up to 14 Trotter steps of time evolution are performed, employing 13,858 two-qubit gates (with a CNOT depth of 370). The propagation of hadrons is clearly identified, with results that compare favorably with Matrix Product State simulations. Prospects for a near-term quantum advantage in simulations of hadron scattering are discussed.

We present strong numerical evidence for the existence of an infrared fixed point in the renormalization group flow of the SU(3) gauge-fermion system with twelve massless fermions in the fundamental representation. Our numerical simulations using nHYP-smeared staggered fermions with Pauli-Villars improvement do not exhibit any first-order bulk phase transition in the investigated parameter region. We utilize an infinite volume renormalization scheme based on the gradient flow transformation to determine the renormalization group $\beta$ function. The gradient flow $\beta$ function exhibits a zero at $g_{\mathrm{GF}\star }^2=6.60(62)$, implying that the system is infrared conformal. We calculate the leading irrelevant critical exponent ${\gamma }_g^{\star }=0.199(32)$. Our prediction for ${\gamma }_g^{\star }$ is consistent with available literature at the $1\text{−}2\sigma$ level.

We analyze the color-magnetic (or “$B$”) field two-point function that encodes the finite-mass correction to the heavy-quark momentum-diffusion coefficient. The simulations are done on fine isotropic lattices in the quenched approximation at $1.5T_c$, using a range of gradient flow times for noise suppression and operator renormalization. The continuum extrapolation is performed at fixed flow time followed by a second extrapolation to zero flow time. Perturbative calculations to next-to-leading order of this correlation function, matching gradient-flowed correlators to $\overline{\mathrm{MS}}$, are used to resolve nontrivial renormalization issues. We perform a spectral reconstruction based on perturbative model fits to estimate the coefficient ${\kappa }_B$ of the finite-mass correction to the heavy-quark momentum-diffusion coefficient. The approach we present here yields high-precision data for the correlator with all renormalization issues incorporated at next-to-leading order and is also applicable for actions with dynamical fermions.

The baryon mass operator is studied within a combined expansion in $1/N_c$ and perturbative $SU(3)$ flavor symmetry breaking, where $N_c$ denotes the number of color charges. Flavor projection operators are used to classify the baryon operators involved in the expansion, which fall into the flavor representations 1, 8, $10+\overline{10}$, 27, $35+\overline{35}$, and 64. This approach allows one to incorporate up to third-order flavor symmetry breaking in the baryon mass operator in a rigorous and systematic way. Previous work on the subject is considered to validate the approach. A fit to data is performed to evaluate the free parameters in the theory and to produce some numerical values of baryon masses. Results are consistent and reaffirm the striking success of the $1/N_c$ expansion.

We present the first theoretical calculation of nonfactorizable charm-quark loop contributions to the $B_s\to \gamma l^{+}{l}^{-}$ amplitude. We calculate the relevant form factors, $H_{A,V}^{\mathrm{NF}}(k^{\prime 2},k^2)$, and provide convenient parametrizations of our results in the form of fit functions of two variables, $k^{\prime 2}$ and $k^2$, applicable in the region below hadron resonances, $k^{\prime 2}<M_{J/\psi }^2$ and $k^2<M_{\varphi }^2$. We report that factorizable and nonfactorizable charm contributions to the $B_s\to \gamma l^{+}{l}^{-}$ amplitude have opposite signs. To compare the charm and the top contributions, it is convenient to express nonfactorizable charming loop contribution as a nonuniversal (i.e., dependent on the reaction) $q^2$-dependent correction ${\mathrm{\Delta }}^{\mathrm{NF}}{C}_7(q^2)$ to the Wilson coefficient $C_7$. For the $B_s\to \gamma l^{+}{l}^{-}$ amplitude, the correction is found to be positive, ${\mathrm{\Delta }}^{\mathrm{NF}}{C}_7(q^2)/C_7>0$.

Nuclear collisions at sufficiently high energies are expected to produce far-from-equilibrium matter with a high density of gluons at early times. We show gauge condensation, which occurs as a consequence of the large density of gluons. To identify this condensation phenomenon, we construct two local gauge invariant observables that carry the macroscopic zero mode of the gauge condensate. The first order parameter for gauge condensation investigated here is the correlator of the spatial Polyakov loop. We also consider, for the first time, the correlator of the gauge invariant scalar field, associated with the exponent of the Polyakov loop. Using real-time lattice simulations of classical-statistical SU(2) gauge theory, we find gauge condensation on a system-size-dependent timescale $t_{\mathrm{cond}}\sim L^{1/\zeta }$ with a universal scaling exponent $\zeta$. Furthermore, we suggest an effective theory formulation describing the dynamics using one of the order parameters identified. The formation of a condensate at early times may have intriguing implications for the early stages in heavy-ion collisions.

The vectorlike quark model is one of the extensions of the standard model (SM) of particle physics. The simplest version of this model introduces a vectorlike singlet quark which can mix with SM quarks and give rise to new contributions to the flavor-changing decays of the Higgs boson. In this work we first present a systematic analysis of the branching ratios of the decays $H\to b\overline{s},b\overline{d}$ at leading order in the standard model. Our results show that it is challenging to observe these two modes because of their small branching ratios. Then augmenting the SM with a vectorlike singlet top quark, assuming the top partner only mixes with the top quark, complete one-loop contributions are taken into account in the amplitudes. Further results indicate that the branching ratios of the decays $H\to b\overline{s},b\overline{d}$ are sensitive to the mass of the top partner $M_T$ and the mixing effects characterized by $\sin {\theta }_L$. By tuning the values of $M_T$ and $\sin {\theta }_L$, the branching ratios may rise to a level accessible to LHC experiments. Combined with the branching ratios obtained from a probabilistic model, the allowed areas in the $M_T-\sin {\theta }_L$ plane are displayed. Tagging efficiencies and feasibility for detecting $H\to b\overline{s}$ are specifically discussed and we conclude that with large statistics it is promising to discover the $H\to b\overline{s}$ decay at the LHC.