The results of an amplitude analysis of the charmless three-body decay $B^{+}\to {\pi }^{+}{\pi }^{+}{\pi }^{-}$, in which $CP$-violation effects are taken into account, are reported. The analysis is based on a data sample corresponding to an integrated luminosity of $3{\mathrm{fb}}^{-1}$ of $pp$ collisions recorded with the LHCb detector. The most challenging aspect of the analysis is the description of the behavior of the ${\pi }^{+}{\pi }^{-}S$-wave contribution, which is achieved by using three complementary approaches based on the isobar model, the $K$-matrix formalism, and a quasi-model-independent procedure. Additional resonant contributions for all three methods are described using a common isobar model, and include the $\rho (770{)}^0$, $\omega (782)$ and $\rho (1450{)}^0$ resonances in the ${\pi }^{+}{\pi }^{-}$ $P$-wave, the $f_2(1270)$ resonance in the ${\pi }^{+}{\pi }^{-}$ $D$-wave, and the ${\rho }_3(1690{)}^0$ resonance in the ${\pi }^{+}{\pi }^{-}$ $F$-wave. Significant $CP$-violation effects are observed in both $S$- and $D$-waves, as well as in the interference between the $S$- and $P$-waves. The results from all three approaches agree and provide new insight into the dynamics and the origin of $CP$-violation effects in $B^{+}\to {\pi }^{+}{\pi }^{+}{\pi }^{-}$ decays.

We construct a solvable deformation of two-dimensional theories with (2, 2) supersymmetry using an irrelevant operator which is a bilinear in the supercurrents. This supercurrent-squared operator is manifestly supersymmetric and equivalent to $T\overline{T}$ after using conservation laws. As illustrative examples, we deform theories involving a single (2, 2) chiral superfield. We show that the deformed free theory is on-shell equivalent to the (2, 2) Nambu-Goto action. At the classical level, models with a superpotential exhibit more surprising behavior: the deformed theory exhibits poles in the physical potential which modify the vacuum structure. This suggests that irrelevant deformations of $T\overline{T}$ type might also affect infrared physics.

We compute anomalous transport phenomena sourced by vector and axial magnetic fields in out-of-equilibrium setups produced by Vaidya background metrics in holography. We use generalized Vaidya metrics that include momentum relaxation induced by massless scalar fields. While the background metric and gauge field show formally instantaneous thermalization, the chiral magnetic effect has significantly large equilibration times. We study how the equilibration of the chiral magnetic effect depends on the length of the Vaidya quench and the momentum relaxation parameter. These results shed some light on aspects of the chiral magnetic effect in out-of-equilibrium situations such as the quark gluon plasma produced in heavy ion collisions.

Voids have emerged as a novel probe of cosmology and large-scale structure. These regions of extreme underdensity are sensitive to physics beyond the standard model of cosmology and can potentially be used as a testing ground to constrain new physics. We present the first determination of the linear void bias measured in separate universe simulations. Our methods are validated by comparing the separate universe response bias with the clustering bias of voids. We find excellent agreement between the two methods for voids identified in the halo field and the down-sampled dark matter field. For voids traced by halos, we identify two different contributions to the bias. The first is due to the bias of the underlying halo field used to identify voids, while the second we attribute to the dynamical impact of long-wavelength density perturbations on void formation and expansion. By measuring these contributions individually, we demonstrate that their sum is consistent with the total void bias. We also measure the void profiles in our simulations, and determine their separate universe response. These can be interpreted as the sensitivity of the profiles to the background density of the Universe.

Primordial black holes may have formed in the radiative era of the early Universe from the collapse of large enough amplitude perturbations of the metric. These correspond to non linear energy density perturbations characterized by an amplitude larger than a certain threshold, measured when the perturbations reenter the cosmological horizon. The process of primordial black hole formation is studied here within spherical symmetry, using the gradient expansion approximation in the long wavelength limit, where the pressure gradients are small, and the initial perturbations are functions only of a time-independent curvature profile. In this regime it is possible to understand how the threshold for primordial black hole formation depends on the shape of the initial energy density profile, clarifying the relation between local and averaged measures of the perturbation amplitude. Although there is no universal threshold for primordial black hole formation, the averaged mass excess of the perturbation depends on the amplitude of the energy density peak, and it is possible to formulate a well-defined criterion to establish when a cosmological perturbation is able to form a black hole in terms of one of these two key quantities. This gives understanding of how the abundance of primordial black holes depends on the shape of the inflationary power spectrum of cosmological perturbations.

While the classification of ${\alpha }^{\prime }$ corrections of string inspired effective theories remains an unsolved problem, we show how to classify duality invariant ${\alpha }^{\prime }$ corrections for purely time-dependent (cosmological) backgrounds. We determine the most general duality invariant theory to all orders in ${\alpha }^{\prime }$ for the metric, $b$-field, and dilaton. The resulting Friedmann equations are studied when the spatial metric is a time-dependent scale factor times the Euclidean metric and the $b$-field vanishes. These equations can be integrated perturbatively to any order in ${\alpha }^{\prime }$. We construct nonperturbative solutions and display duality invariant theories featuring string-frame de Sitter vacua.

Coherent elastic neutrino-nucleus scattering (CEvNS) is calculated to be the dominant neutrino scattering channel for neutrinos of energy $E_{\nu }<100\mathrm{MeV}$. We report a limit for this process from data collected in an engineering run of the 29 kg CENNS-10 liquid argon detector located 27.5 m from the pion decay-at-rest neutrino source at the Oak Ridge National Laboratory Spallation Neutron Source (SNS) with $4.2\times {10}^{22}$ protons on target. The dataset provided constraints on beam-related backgrounds critical for future measurements and yielded $<7.4$ candidate CEvNS events which implies a cross section for the process, averaged over the SNS pion decay-at-rest flux, of $<3.4\times {10}^{-39}{\mathrm{cm}}^2$, a limit within twice the Standard Model prediction. This is the first limit on CEvNS from an argon nucleus and confirms the earlier CsI[Na] nonstandard neutrino interaction constraints from the collaboration. This run demonstrated the feasibility of the ongoing experimental effort to detect CEvNS with liquid argon.

We analyze joint angular distributions of a charmonium decay to the $\mathrm{\Xi }\overline{\mathrm{\Xi }}$ pair using the $\mathrm{\Xi }\to \mathrm{\Lambda }\pi \to p{\pi }^{-}\pi$ weak decay chain for the cascade and the charge conjugated mode for the anticascade. The decays allow a direct comparison of the baryon and antibaryon decay properties and a sensitive test of $CP$ symmetry in the strange baryon sector. We show that all involved decay parameters can be determined separately in vector and (pseudo)scalar charmonia decays into $\mathrm{\Xi }\overline{\mathrm{\Xi }}$ due to the spin correlations between the weak decay chains. Contrary to the recently measured $e^{+}{e}^{-}\to J/\psi \to \mathrm{\Lambda }\overline{\mathrm{\Lambda }}$ process, the transverse polarization of the cascade is not needed and has almost no impact on the uncertainties of the decay parameters.

Neutron stars provide an excellent laboratory for physics under the most extreme conditions. Up to now, models of axisymmetric, stationary, differentially rotating neutron stars were constructed under the strong assumption of barotropicity, where a one-to-one relation between all thermodynamic quantities exists. This implies that the specific angular momentum of a matter element depends only on its angular velocity. The physical conditions in the early stages of neutron stars, however, are determined by their violent birth processes, typically a supernova or in some cases the merger of two neutron stars, and detailed numerical models show that the resulting stars are by no means barotropic. Here, we construct models for stationary, differentially rotating, nonbarotropic neutron stars, where the equation of state and the specific angular momentum depend on more than one independent variable. We show that the potential formulation of the relativistic Euler equation can be extended to the nonbarotropic case, which, to the best of our knowledge, is a new result even for the Newtonian case. We implement the new method into the XNS code and construct equilibrium configurations for nonbarotropic equations of state. We scrutinize the resulting configurations by evolving them dynamically with the numerical relativity code BAM, thereby demonstrating that the new method indeed produces stationary, differentially rotating, nonbarotropic neutron star configurations.

It is well known that r-mode oscillations of rotating neutron stars may be unstable with respect to the gravitational wave emission. It is highly unlikely to observe a neutron star with the parameters within the instability window, a domain where this instability is not suppressed. But if one adopts the “minimal” (nucleonic) composition of the stellar interior, a lot of observed stars appear to be within the r-mode instability window. One of the possible solutions to this problem is to account for hyperons in the neutron-star core. The presence of hyperons allows for a set of powerful (lepton-free) nonequilibrium weak processes, which increase the bulk viscosity and thus suppress the r-mode instability. Existing calculations of the instability windows for hyperon neutron stars generally use reaction rates calculated for the ${\mathrm{\Sigma }}^{-}\mathrm{\Lambda }$ hyperonic composition via the contact $W$-boson-exchange interaction. In contrast, here we employ hyperonic equations of state where the $\mathrm{\Lambda }$ and ${\mathrm{\Xi }}^{-}$ are the first hyperons to appear (the ${\mathrm{\Sigma }}^{-}$’s, if they are present, appear at much larger densities) and consider the meson-exchange channel, which is more effective for the lepton-free weak processes. We calculate the bulk viscosity for the nonpaired $npe\mu \mathrm{\Lambda }{\mathrm{\Xi }}^{-}$ matter using the meson-exchange weak interaction. A number of viscosity-generating nonequilibrium processes is considered (some of them for the first time in the neutron-star context). The calculated reaction rates and bulk viscosity are approximated by simple analytic formulas, easy to use in applications. Applying our results to calculation of the instability window, we argue that accounting for hyperons may be a viable solution to the r-mode problem.

Asymptotic particle states in four-dimensional celestial scattering amplitudes are labeled by their $SL(2,\mathbb{C})$ Lorentz/conformal weights $(h,\overline{h})$ rather than the usual energy-momentum four-vector. These boost eigenstates involve a superposition of all energies. As such, celestial gluon (or photon) scattering cannot obey the usual (energetically) soft theorems. In this paper we show that tree-level celestial gluon scattering, in theories with sufficiently soft UV behavior, instead obeys conformally soft theorems involving $h\to 0$ or $\overline{h}\to 0$. Unlike the energetically soft theorem, the conformally soft theorem cannot be derived from low-energy effective field theory.

We report on the end state of nonaxisymmetric instabilities of singly spinning asymptotically flat Myers-Perry black holes. Starting from a singly spinning black hole in $D=5$, 6, 7 dimensions, we introduce perturbations with angular dependence described by $m=2$, $m=3$, or $m=4$ azimuthal mode numbers about the axis of rotation. In $D=5$, we find that all singly spinning Myers-Perry black holes are stable, in agreement with the results from perturbation theory. In $D=6$ and 7, we find that these black holes are nonlinearly stable only for sufficiently low spins. For intermediate spins, although the $m=2$ bar mode becomes unstable and leads to large deformations, the black hole settles back down to another member of the Myers-Perry family via gravitational wave emission; surprisingly, we find that all such unstable black holes settle to what appear to be the same member of the Myers-Perry family. The amount of energy radiated into gravitational waves can be very large, in some cases more than 30% of the initial total mass of the system. For high enough spins, the $m=4$ mode becomes the dominant unstable mode, leading to deformed black holes that develop local Gregory-Laflamme instabilities, thus forming a naked singularity in finite time, which is further evidence for the violation of the weak cosmic censorship conjecture in asymptotically flat higher-dimensional spacetimes.

We propose a kinematic method based on a factorization formula for precisely measuring the top quark mass $m_t$ in $pp$ collisions using boosted top jets with light soft drop grooming. By using light grooming, which is an order of magnitude less aggressive than typical grooming, we retain a universal description of the top-mass scheme and decay effects, while still effectively removing soft contamination from the top jet. We give field theory results for the hadronization corrections for jets induced by a heavy top quark, showing they are described by a universal hadronic parameter that also appears for groomed light quark jets. An important phenomenological application of our results is that one can obtain $m_t$ in a short distance scheme by fitting the hadron level jet mass distributions, predicted by our factorization formula, to data or by Monte Carlo calibration. The peaked distributions for $pp$ and $e^{+}{e}^{-}$ collisions are similar, up to sensitivity to an underlying event which is significantly reduced by the soft drop. Since the soft drop implies that the $t$ and $\overline{t}$ jet masses each can be independently measured, the analysis enables the use of $\mathrm{lepton}+\text{jet}$ samples.

The ratio of dilepton production cross sections on a proton, using the $\gamma p\to l^{+}{l}^{-}p$ process, above and below the dimuon production threshold allows one to extract the effective lepton-proton interaction, which is required to be identical for electrons and muons if lepton universality is exact. To test for a scenario of broken universality at the percent level, of the size that could explain the different proton charge radii extracted from electron scattering and from muonic hydrogen spectroscopy, we evaluate all one-loop QED corrections to this process, including the full lepton mass dependencies. We furthermore show that two photon–exchange processes with both photons attached to the proton line vanish after averaging over dilepton angles and estimate the relatively small radiation off the proton. We compare the full one-loop calculation with a soft-photon approximation of the same order and present estimates for a planned experiment.

Kinetic Sunyaev Zel’dovich (kSZ) tomography provides a powerful probe of the radial velocity field of matter in the Universe. By cross-correlating a high resolution cosmic microwave background (CMB) experiment like CMB-S4 and a galaxy survey like Dark Energy Spectroscopic Instrument (DESI) or Large Synoptic Survey Telescope (LSST), one can measure the radial velocity field with a very high signal-to-noise ratio over a large volume of the universe. In this paper we show how this measurement can be used to improve constraints on primordial non-Gaussianities of the local type. The velocity field provides a measurement of the unbiased matter perturbations on large scales, which can be cross-correlated with the biased large-scale galaxy density field. This results in sample variance cancellation for a measurement of scale-dependent bias due to a nonzero $f_{NL}$. Using this method we forecast that CMB-S4 and LSST combined reach a sensitivity ${\sigma }_{f_{NL}}\sim 0.5$, which is a factor of 3 improvement over the sensitivity using LSST alone (without internal sample variance cancellation). We take into account critical systematics like photometric redshifts, the kSZ optical depth degeneracy, and systematics affecting the shape of the galaxy auto-power spectrum and find that these have negligible impact, thus making kSZ tomography a robust probe for primordial non-Gaussianities. We also forecast the impact of mass binning on our constraints. The techniques proposed in this paper could be an important component of achieving the theoretically important threshold of ${\sigma }_{f_{NL}}\lesssim 1$ with future surveys.

The redshifted 21-cm line of hydrogen holds great potential for the study of cosmology, as it can probe otherwise unobservable cosmic epochs. In particular, measurements of the 21-cm power spectrum during cosmic dawn—the era when the first stars were formed—will provide us with a wealth of information about the astrophysics of stellar formation, as well as the origin of fluctuations intn our Universe. In addition to their usually considered density fluctuations, dark matter and baryons possess large relative velocities with respect to each other, due to the baryon acoustic oscillations suffered by the latter, which suppress the formation of stars during cosmic dawn, leaving an imprint on 21-cm observables during this era. Here we present 21cmvfast, a version of the publicly available code 21cmvfast modified to account for this effect. Previous work has shown that the inclusion of relative velocities produces an acoustic modulation on the large-scale 21-cm power spectrum during cosmic dawn. By comparing analytic calculations with simulations from 21cmvfast, here we demonstrate that this modulation takes the form of robust velocity-induced acoustic oscillations (VAOs), during both the Lyman-$\alpha$ coupling era and the subsequent epoch of heating. The unique shape of these VAOs, which is determined by the acoustic physics that generated the relative velocities, can be analytically computed and is easily distinguishable from the usual density-sourced fluctuations. We find that, under a broad range of astrophysical assumptions, the VAOs are detectable at high significance by the upcoming HERA interferometer, which could therefore confirm the presence of acoustic oscillations at cosmic dawn.

The dipion transitions $\mathrm{\Upsilon }(2S,3S,4S)\to \mathrm{\Upsilon }(1S,2S)\pi \pi$ are systematically studied by considering the mechanisms of the hadronization of soft gluons, exchanging the bottomoniumlike $Z_b$ states, and the bottom-meson loops. The strong pion-pion final-state interaction, especially including the channel coupling to $K\overline{K}$ in the $S$-wave, is taken into account in a model-independent way using the dispersion theory. Through fitting to the available experimental data, we extract values of the transition chromopolarizabilities $|{\alpha }_{\mathrm{\Upsilon }(mS)\mathrm{\Upsilon }(nS)}|$, which measure the chromoelectric couplings of the bottomonia with soft gluons. It is found that the $Z_b$ exchange has a slight impact on the extracted chromopolarizablity values, and the obtained $|{\alpha }_{\mathrm{\Upsilon }(2S)\mathrm{\Upsilon }(1S)}|$ considering the $Z_b$ exchange is $(0.29\pm 0.20){\mathrm{GeV}}^{-3}$. Our results could be useful in studying the interactions of bottomonium with light hadrons.

We explore the large spin spectrum in two-dimensional conformal field theories with a finite twist gap, using the modular bootstrap in the light-cone limit. By recursively solving the modular crossing equations associated with different $PSL(2,\mathbb{Z})$ elements, we identify the universal contribution to the density of large spin states from the vacuum in the dual channel. Our result takes the form of a sum over $PSL(2,\mathbb{Z})$ elements, whose leading term generalizes the usual Cardy formula to a wider regime. Rather curiously, the contribution to the density of states from the vacuum becomes negative in a specific limit, which can be canceled by that from a nonvacuum Virasoro primary whose twist is no bigger than $\frac{c-1}{16}$. This suggests a new upper bound of $\frac{c-1}{16}$ on the twist gap in any $c>1$ compact, unitary conformal field theory with a vacuum, which would in particular imply that pure ${\mathrm{AdS}}_3$ gravity does not exist. We confirm this negative density of states in the pure gravity partition function by Maloney, Witten, and Keller. We generalize our discussion to theories with $\mathcal{N}=(1,1)$ supersymmetry and find similar results.

In this paper we study the two-body gravitational scattering of massive scalars with different masses in general spacetime dimensions. We focus on the Regge limit (eikonal regime) of the resulting scattering amplitudes and discuss how to extract the classical information representing the scattering of two black holes. We derive the leading eikonal and explicitly show the resummation of the first leading energy contribution up to second order in Newton’s gravitational constant. We also calculate the subleading eikonal showing that in general spacetime dimensions it receives a nontrivial contribution from the box integral. From the eikonal we extract the two-body classical scattering angle between the two black holes up to the second post-Minkowskian order. Taking various probe-limits of the two-body scattering angles we are able to show agreement between our results and various results in the literature. We highlight that the box integral also has a log-divergent (in energy) contribution at subsubleading order which violates perturbative unitarity in the ultrarelativistic limit. We expect this term to play a role in the calculation of the eikonal at the third post-Minkowskian order.

We present a theoretical analysis of an electron confined by a Penning trap, also known as geonium, that is affected by gravity. In particular, we investigate the gravitational influence on the electron dynamics and the electromagnetic field of the trap. We consider the special case of a homogeneous gravitational field, which is represented by Rindler spacetime. In this spacetime the Hamiltonian of an electron with anomalous magnetic moment is constructed. Based on this Hamiltonian and the exact solution to Maxwell equations for the field of a Penning trap in Rindler spacetime, we derive the transition energies of geonium up to the relativistic corrections of $1/{\mathrm{c}}^2$. These transition energies are used to obtain an extension of the well known ${\mathrm{g}}_s$-factor formula introduced by L. S. Brown and G. Gabrielse [Rev. Mod. Phys. 58, 233 1986].