We discuss how electromagnetically dualizing a 1-form to a 2-form in ${\mathrm{AdS}}_5$ exchanges regular and alternate boundary conditions, and thus gauges the originally global $U(1)$ symmetry in the dual field theory. The generalized symmetry current dual to the 2-form in the bulk is identified as the dual field strength of the gauged $U(1)$, and the associated double-trace operator with a logarithmically running coupling is just the gauged $U(1)$ Maxwell action. Applying this dualization to an AdS Maxwell-Chern-Simons theory dual to a global $U(1)\times U(1)$ model with a ’t Hooft anomaly results in a theory with a modified field strength that holographically realizes a 2-group symmetry. We explicitly carry out the holographic renormalization to verify this, and discuss the generalization to other rank fields in other dimensions.

A minimal requirement for any strongly coupled gauge field theory to have a classical dual bulk gravity description is that one should in principle be able to recover the full geometry as encoded on the asymptotics of the spacetime. Even this requirement cannot be fulfilled with arbitrary precision simply due to the fact that the boundary data is inherently noisy. We present a statistical approach to bulk reconstruction from entanglement entropy measurements, which handles the presence of noise in a natural way. Our approach therefore opens up a novel gateway for precision holography.

Production of massless, scalar particles by a relativistic, semitransparent, plane mirror in $(1+3)\mathrm{D}$ Minkowski spacetime based on the Barton-Calogeracos (BC) action is investigated. The corresponding Bogoliubov coefficients are derived for a mirror with arbitrary, relativistic trajectories. We apply our derived formula to two specific trajectories. One is commonly used in the $(1+1)\mathrm{D}$ literature to mimic gravitational collapse theoretically, and the other is proposed to be realizable experimentally. In addition, we identify the relation between the particle spectrum and the particle production probability, and we demonstrate the equivalence between our approach and the existing approach in the literature, which is restricted to $(1+1)\mathrm{D}$. In short, our treatment extends the study to $(1+3)\mathrm{D}$ spacetime for a relativistic, plane mirror. Lastly, we offer a third approach for finding the particle spectrum using the S-matrix formalism.

The geodesic equation encodes test-particle dynamics at arbitrary gravitational coupling, hence retaining all orders in the post-Minkowskian (PM) expansion. Here we explore what geodesic motion can tell us about dynamical scattering in the presence of perturbatively small effects such as tidal distortion and higher derivative corrections to general relativity. We derive an algebraic map between the perturbed geodesic equation and the leading PM scattering amplitude at arbitrary mass ratio. As examples, we compute formulas for amplitudes and isotropic gauge Hamiltonians for certain infinite classes of tidal operators such as electric or magnetic Weyl to any power, and for higher derivative corrections to gravitationally interacting bodies with or without electric charge. Finally, we present a general method for calculating closed-form expressions for amplitudes and isotropic gauge Hamiltonians in the test-particle limit at all orders in the PM expansion.

Galileons are scalar field theories which obey the Galileon symmetry $\phi \to \phi +b+c_{\mu }{x}^{\mu }$ and are capable of self-acceleration if they have an inverted sign for the kinetic term. These theories violate the strong equivalence principle, such that black holes (BHs) do not couple to the Galileon field, whereas nonrelativistic objects experience a fifth force with strength $\mathrm{\Delta }G/G_{\mathrm{N}}$ relative to gravity. For galaxies falling down a gradient in the Galileon field, this results in an offset between the center of the galaxy and its host supermassive BH. We reconstruct the local gravitational and Galileon fields through a suite of constrained N-body simulations (which we dub CSiBORG) and develop a Monte Carlo-based forward model for these offsets on a galaxy-by-galaxy basis. Using the measured offset between the optical center and active galactic nucleus of 1916 galaxies from the literature, propagating uncertainties in the input quantities and marginalizing over an empirical noise model describing astrophysical and observational noise, we constrain the Galileon coupling to be $\mathrm{\Delta }G/G_{\mathrm{N}}<0.16$ at $1\sigma$ confidence for Galileons with crossover scale $r_{\mathrm{C}}\gtrsim H_0^{-1}$.

Searches for gravitational waves from compact binaries focus mostly on quasicircular motion with the rationale that wave emission circularizes the orbit. Here, we study the generality of this result, when astrophysical environments (e.g., accretion disks) or other fundamental interactions are taken into account. We are motivated by possible electromagnetic counterparts to binary black hole coalescences and orbits, but also by the possible use of eccentricity as a smoking gun for new physics. We find that (i) backreaction from radiative mechanisms, including scalars, vectors and gravitational waves, circularize the orbital motion. (ii) By contrast, environmental effects such as accretion and dynamical friction increase the eccentricity of binaries. Thus, it is the competition between radiative mechanisms and environmental effects that dictates the eccentricity evolution. We study this competition within an adiabatic approach, including gravitational radiation and dynamical friction forces. We show that there is a critical semimajor axis below which gravitational radiation dominates the motion and the eccentricity of the system decreases. However, the eccentricity inherited from the environment-dominated stage can be substantial, and in particular can affect LISA sources. We provide examples for GW190521-like sources.

The precise values of the running quark and lepton masses $m_f(\mu )$, which are defined in the modified minimal subtraction scheme with $\mu$ being the renormalization scale and the subscript $f$ referring to all the charged fermions in the Standard Model (SM), are very useful for the model building of fermion masses and flavor mixing and for the precision calculations in the SM or its new-physics extensions. In this paper, we calculate the running fermion masses by taking account of the up-to-date experimental results collected by Particle Data Group and the latest theoretical higher-order calculations of relevant renormalization-group equations and matching conditions in the literature. The emphasis is placed on the quantitative estimation of current uncertainties on the running fermion masses, and the linear error propagation method is adopted to quantify the uncertainties, which has been justified by the Monte Carlo simulations. We identify two main sources of uncertainties, i.e., one from the experimental inputs and the other from the truncations at finite-order loops. The correlations among the uncertainties of running parameters can be remarkable in some cases. The final results of running fermion masses at several representative energy scales are tabulated for further applications.

We present a realistic, simple, and natural model of self-interacting dark matter based on the neutrino-portal paradigm. The self-interactions at small velocities are generated by the exchange of dark photons and produce the observed core-like DM distribution in galactic centers. This effect could be spoiled by the formation of DM bound states (also due to dark-photon effects), which we avoid by requiring the DM candidates to be light, with masses below $O(10\mathrm{GeV})$. The mixing of the dark photon with the $Z$ and ordinary photon is strongly suppressed by introducing a softly broken discrete symmetry similar to charge conjugation, which also ensures that the dark photon lifetime is short enough to avoid restrictions derived form big-bang nucleosynthesis and large-scale structure formation. Other constraints are accommodated without the need of fine tuning, in particular nucleon scattering occurs only at one loop, so direct detection cross sections are naturally suppressed. Neutrino masses are generated through the inverse seesaw.

We study the phase diagram and critical behavior of a two-dimensional lattice $\mathrm{SO}(N_c)$ gauge theory ($N_c\ge 3$) with two scalar flavors, obtained by partially gauging a maximally $\mathrm{O}(2N_c)$ symmetric scalar model. The model is invariant under local $\mathrm{SO}(N_c)$ and global O(2) transformations. We show that, for any $N_c\ge 3$, it undergoes finite-temperature Berezinskii-Kosterlitz-Thouless (BKT) transitions, associated with the global Abelian O(2) symmetry. The transition separates a high-temperature disordered phase from a low-temperature spin-wave phase where correlations decay algebraically (quasi-long range order). The critical properties at the finite-temperature BKT transition and in the low-temperature spin-wave phase are determined by means of a finite-size scaling analysis of Monte Carlo data.

The continuous multiscale entaglement renormalization ansatz (cMERA) [Haegeman et al., Phys. Rev. Lett. 110, 100402 (2013)] is a variational wave functional for ground states of quantum field theories. So far, only scalar bosons and fermions have been considered. In this paper we explain how to generalize the cMERA framework to gauge invariant quantum fields. The fundamental difficulty to be addressed is how to make the gauge constraints (local linear constraints in the Hilbert space) compatible with the UV structure of the cMERA wave functional (which is generated by a quasilocal entangler). For simplicity, we consider U(1) gauge theory in $d+1$ spacetime dimensions, a noninteracting theory with massless Hamiltonian $H_{\mathrm{U}(1)}$ and Gaussian scale invariant ground state $|{\mathrm{\Psi }}_{\mathrm{U}(1)}⟩$. We propose a gauge invariant cMERA wave functional $|{\mathrm{\Psi }}_{\mathrm{U}(1)}^{\mathrm{\Lambda }}⟩$ that, by construction, accurately reproduces the long distance properties of $|{\mathrm{\Psi }}_{\mathrm{U}(1)}⟩$ while remaining somewhat unentangled at short distances. Moreover, $|{\mathrm{\Psi }}_{\mathrm{U}(1)}^{\mathrm{\Lambda }}⟩$ is the exact ground state of a gauge invariant, local Hamiltonian $H_{\mathrm{U}(1)}^{\mathrm{\Lambda }}$ whose low energy properties coincide with those of $H_{\mathrm{U}(1)}$. Our construction also extends the cMERA formalism to massive (nongauge invariant) vector boson quantum fields.

We reanalyze the gravitational-wave event GW190412 with state-of-the-art phenomenological waveform models. This event, which has been associated with a black hole merger, is interesting due to the significant contribution from subdominant harmonics. We use both frequency-domain and time-domain waveform models. The PhenomX waveform models constitute the fourth generation of frequency-domain phenomenological waveforms for black hole binary coalescence; they have more recently been complemented by the time-domain PhenomT models, which open up new strategies to model precession and eccentricity, and to perform tests of general relativity with the phenomenological waveforms approach. Both PhenomX and PhenomT have been constructed with similar techniques and accuracy goals, and due to their computational efficiency this “generation X” model family allows the routine use of subdominant spherical harmonics in Bayesian inference. We show the good agreement between these and other state-of-the-art waveform models for GW190412, and discuss the improvements over the previous generation of phenomenological waveform models. We also discuss practical aspects of Bayesian inference such as run convergence, variations of sampling parameters, and computational cost.

We perform a novel test of general relativity by measuring the gravitational constant in the Large Magellanic Cloud (LMC). The LMC contains six well-studied Cepheid variable stars in detached eclipsing binaries. Radial velocity and photometric observations enable a complete orbital solution, and precise measurements of the Cepheids’ periods permit detailed stellar modelling. Both are sensitive to the strength of gravity, the former via Kepler’s third law and the latter through the gravitational free-fall time. We jointly fit the observables for stellar parameters and the gravitational constant. Performing a full Markov Chain Monte Carlo analysis of the parameter space including all relevant nuisance parameters, we constrain the gravitational constant in the Large Magellanic Cloud relative to the Solar System to be $G_{\mathrm{LMC}}/G_{\mathrm{SS}}=0.93_{-0.04}^{+0.05}$. We discuss the implications of this 5% measurement of Newton’s constant in another galaxy for dark energy and modified gravity theories. This result excludes one Cepheid, CEP-1812, which is an outlier and needs further study: it is either a highly unusual system to which our model does not apply, or it prefers $G_{\mathrm{LMC}}<G_{\mathrm{SS}}$ at $2.6\sigma$. We also obtain new bounds on critical parameters that appear in semianalytic descriptions of stellar processes. In particular, we measure the mixing length parameter to be $\alpha =0.90_{-0.26}^{+0.36}$ (when assumed to be constant across our sample), and obtain constraints on the parameters describing turbulent dissipation and convective flux.

A relativistic theory of gravity like general relativity produces phenomena differing fundamentally from Newton’s theory. An example, analogous to electromagnetic induction, is gravitomagnetism, or the dragging of inertial frames by mass-energy currents. These effects have recently been confirmed by classical observations. Here we show, for the first time, that they can be observed by a quantum detector. We study the response function of Unruh De-Witt detectors placed in a slowly rotating shell. We show that the response function picks up the presence of rotation even though the spacetime inside the shell is flat and the detector is locally inertial. The detector can distinguish between the static situation when the shell is nonrotating and the stationary case when the shell rotates and the dragging of inertial frames, i.e., gravitomagnetic effects, arise. Moreover, it can do so when the detector is switched on for a finite time interval within which a light signal cannot travel to the shell and back to convey the presence of rotation.

Spinning black holes store rotational energy that can be extracted. When a black hole is immersed in an externally supplied magnetic field, reconnection of magnetic field lines within the ergosphere can generate negative energy (relative to infinity) particles that fall into the black hole event horizon while the other accelerated particles escape stealing energy from the black hole. We show analytically that energy extraction via magnetic reconnection is possible when the black hole spin is high (dimensionless spin $a\sim 1$) and the plasma is strongly magnetized (plasma magnetization ${\sigma }_0>1/3$). The parameter space region where energy extraction is allowed depends on the plasma magnetization and the orientation of the reconnecting magnetic field lines. For ${\sigma }_0\gg 1$, the asymptotic negative energy at infinity per enthalpy of the decelerated plasma that is swallowed by a maximally rotating black hole is found to be ${\epsilon }_{-}^{\infty }\simeq -\sqrt{{\sigma }_0/3}$. The accelerated plasma that escapes to infinity and takes away black hole energy asymptotes the energy at infinity per enthalpy ${\epsilon }_{+}^{\infty }\simeq \sqrt{3{\sigma }_0}$. We show that the maximum power extracted from the black hole by the escaping plasma is $P_{\mathrm{extr}}^{\max }\sim 0.1M^2\sqrt{{\sigma }_0}{w}_0$ (here, $M$ is the black hole mass and $w_0$ is the plasma enthalpy density) for the collisionless plasma regime and one order of magnitude lower for the collisional regime. Energy extraction causes a significant spindown of the black hole when $a\sim 1$. The maximum efficiency of the plasma energization process via magnetic reconnection in the ergosphere is found to be ${\eta }_{\max }\simeq 3/2$. Since fast magnetic reconnection in the ergosphere should occur intermittently in the scenario proposed here, the associated emission within a few gravitational radii from the black hole is expected to display a bursty nature.

We study both the $CP$-even and $CP$-odd effective chiral Lagrangians of a next-to-minimal composite Higgs model, with a symmetry breaking pattern depicted by the coset $SO(6)/SO(5)$ through the sigma/omega decomposition, in which the Goldstone matrix of the coset is decomposed in terms of the standard model Higgs doublet and an additional scalar singlet $s$ at the electroweak scale. The effective Lagrangians are described by the electroweak chiral operators up to $p^4$ order, with a function dependence on the Higgs boson and new scalar $s$, named Higgs function. This function in the effective Lagrangian incorporates the Higgs nonlinearity or vacuum misalignment effects in the next-to-minimal composite Higgs model, leads to various Higgs couplings deviated from the standard model ones, and also indicates the relations among different Higgs couplings in the low energy. Matching to the Higgs effective field theory below the electroweak scale, we obtain various low-energy observables such as the electroweak oblique parameters, anomalous triple and quartic gauge couplings, anomalous couplings of Higgs to gauge bosons, in which the Higgs nonlinearity effects are encoded in the ratio $\xi \equiv v^2/f^2$ of the electroweak scale and the new physics scale. As a by-product, we obtain a generalized Maurer-Cartan equation sourced by non-Abelian gauge fields. The equation interprets the dynamical interplay between nonlinear realization of pseudo-Nambu-Goldstone bosons (or Higgs) and the gauge fields, and provides a nonlinear generalization of the dynamical electroweak symmetry breaking.

The implications of the quark sea generation through the chiral fluctuations have been studied in the context of quark flavor distribution functions for the $\text{spin}-{(3/2)}^{+}$ decuplet baryons. The chiral constituent quark model allows a simple and intuitive method to investigate the principle features of the hadron structure and is able to qualitatively generate the requisite amount of quark sea. It is also known to provide a satisfactory justification for the chiral symmetry breaking and SU(3) symmetry breaking. In light of the recent developments to test the mechanism for the quark sea generation, the quark sea asymmetries $\overline{d}-\overline{u}$, $\overline{d}/\overline{u}$ and the fraction of a particular quark $F_q^{B^{*}}=(q^{B^{*}}+{\overline{q}}^{B^{*}}/{\sum }_q(q^{B^{*}}+{\overline{q}}^{B^{*}}))$ have been studied for the $\text{spin}-{(3/2)}^{+}$ decuplet baryons. The suppression factors estimating the strange quark content with respect to the nonstrange quarks in the $\mathrm{\Delta }$ baryons and the suppression factors estimating the $u$ and $d$ quark contents with respect to the strange quarks in ${\mathrm{\Omega }}^{-}$ baryons have also been discussed.

We show that the nonperturbative decay of ultralight scalars into Abelian gauge bosons, recently proposed as a possible solution to the Hubble tension, produces a stochastic background of gravitational waves which is constrained by the cosmic microwave background. We simulate the full nonlinear dynamics of resonant dark photon production and the associated gravitational-wave production, finding the signals to exceed constraints for the entire parameter space we consider. Our findings suggest that gravitational-wave production from the decay of early dark energy may provide a unique probe of these models.

We propose new ADHM-like methods to compute the Coulomb branch instanton partition functions of 5D and 6D supersymmetric gauge theories, with certain exceptional gauge groups or exceptional matters. We study $G_2$ theories with $n_{\mathbf{7}}\le 3$ matters in $\mathbf{7}$ and $SO(7)$ theories with $n_{\mathbf{8}}\le 4$ matters in the spinor representation $\mathbf{8}$. We also study the elliptic genera of self-dual instanton strings of 6D SCFTs with exceptional gauge groups or matters, including all non-Higgsable atomic SCFTs with rank 2 or 3 tensor branches. Some of them are tested with topological vertex calculus. We also explore a D-brane-based method to study instanton particles of 5D $SO(7)$ and $SO(8)$ gauge theories with matters in spinor representations, which further tests our ADHM-like proposals.

Supersymmetric Yang–Mills theory is formulated in six dimensions, without the use of anticommuting variables. This is achieved using a new Nicolai map, to third order in the coupling constant. This is the second such map in six dimensions and highlights a potential ambiguity in the formalism.

Fermionic terms in a class of locally supersymmetric theories called “liberated supergravity” are nonrenormalizable interactions proportional to inverse powers of the supersymmetry breaking scale and Planck mass $M_{\mathrm{pl}}$. This property defines an intrinsic cutoff for liberated supergravities, which are therefore effective theories valid only below energies that never exceed the cutoff. Requiring that the cutoff exceeds current theoretical and observational bounds shows that the new scalar potential terms allowed by liberated supergravity can neither change the cosmological constant predicted by supergravity by any observable amount, nor give measurable contributions to particle masses. We show that it is nevertheless possible to define a simple liberated supergravity model of slow roll inflation valid up to energy scales that are well above the Hubble parameter during inflation and exceeds observable limits after inflation. The key to constructing a viable model is to change the supersymmetry breaking scale, from a Planck-scale value during inflation, to TeV-scale after inflation.