It has been shown that non-Abelian vortex string supported in four-dimensional (4D) $\mathcal{N}=2$ supersymmetric QCD (SQCD) with the U(2) gauge group and $N_f=4$ quark flavors becomes a critical superstring. This string propagates in the ten-dimensional space formed by a product of the flat 4D space and an internal space given by a Calabi-Yau noncompact threefold, namely, the conifold. The spectrum of closed string states of the associated string theory was obtained using the equivalence between the critical string on the conifold and the noncritical string on the semi-infinite cigar described by the $\mathrm{SL}(2,\mathbb{R})/U(1)$ Wess-Zumino-Novikov-Witten model. This spectrum was identified with the spectrum of hadrons in 4D $\mathcal{N}=2$ SQCD. In order to describe effective interactions of these 4D hadrons in this paper, we study correlation functions of normalizable vertex operators localized near the tip of the $\mathrm{SL}(2,\mathbb{R})/\mathrm{U}(1)$ cigar. We also compare our solitonic string approach to the gauge-string duality to the AdS/CFT-type holography for little string theories. The latter relates off mass-shell correlation functions on the field theory side to correlation functions of non-normalizable vertex operators on the cigar. We show that in most channels the holographic approach works in our theory because normalizable and non-normalizable vertex operators with the same conformal dimension are related due to the reflection from the tip of the cigar. However, we find that holography does not work for lightest hadrons with given baryonic charge.

Using the data samples collected in the energy range from 3.773 to 4.600 GeV with the BESIII detector at the BEPCII collider, we measure the dressed cross sections as a function of center-of-mass energy for $e^{+}{e}^{-}\to K^{+}{K}^{-}{\pi }^{+}{\pi }^{-}({\pi }^0)$, $K^{+}{K}^{-}{K}^{+}{K}^{-}({\pi }^0)$, ${\pi }^{+}{\pi }^{-}{\pi }^{+}{\pi }^{-}({\pi }^0)$, and $p\overline{p}{\pi }^{+}{\pi }^{-}({\pi }^0)$. The cross sections for $e^{+}{e}^{-}\to K^{+}{K}^{-}{K}^{+}{K}^{-}{\pi }^0$, $p\overline{p}{\pi }^{+}{\pi }^{-}({\pi }^0)$ are the first measurements. Cross sections for the other five channels are much more precise than previous results in this energy region. We also search for charmonium and charmonium-like resonances, such as the $Y(4230)$, decaying into the same final states. We find evidence of the $\psi (4040)$ decaying to ${\pi }^{+}{\pi }^{-}{\pi }^{+}{\pi }^{-}{\pi }^0$ with a statistical significance of $3.6\sigma$. Upper limits are provided for other decays since no clear signals are observed.

We investigate nonlinear extensions of the holographic soft wall model proposed by Karch et al. [Phys. Rev. D 74, 015005 (2006)] including nonminimal couplings in the five-dimensional action. The nonminimal couplings bring a new parameter $a_0$ which controls the transition between spontaneous and explicit symmetry breaking near the limit of massless quarks (the chiral limit). In the physical region (positive quark mass), we show that above a critical value of the parameter $a_0$ the chiral condensate $⟨\overline{q}q⟩$ is finite in the chiral limit, signifying spontaneous chiral symmetry breaking. This result is supported by the lightest states arising in the spectrum of the pseudoscalar mesons, which become massless in the chiral limit and are therefore intrepreted as Nambu-Goldstone bosons. Moreover, the decay constants of the pseudoscalar mesons also support this conclusion, as well as the Gell-Mann-Oakes-Renner relation satisfied by the lightest states. We also calculate the spectrum of scalar, vector, and axial-vector mesons with their corresponding decay constants. We describe the evolution of masses and decay constants with the increasing of the quark mass, and for the physical mass, we compare our results against available experimental data. Finally, we do not find instabilities in our model for the physical region (positive quark mass).

Lie algebra valued equations translating the integrability of a general two-dimensional Wess-Zumino-Witten model are given. We found a simple solution to these equations and identified a new integrable nonlinear sigma model. This is a two-parameter deformation of the Wess-Zumino-Witten model.

Mode decomposition is crucial for studying the dynamics of propagation in a quantum process. In the quantum treatment of collapsing matter, a viable mode analysis is supposed to give information regarding emission during the collapse. Nevertheless, partly owing to operator ordering ambiguities involved in a typical quantum gravity analysis, the availability of such well-defined modes is not guaranteed. We study the mode decomposition of the unitarily evolving wave packet constructed for the quantum model of spherically symmetric dust collapsing in a marginally bound Lemaître-Tolman-Bondi (LTB) model. We consider a minisuperspace model of dust collapse, where black hole singularity is replaced by a bounce from collapsing phase to expanding phase in the quantum dynamics of the dust cloud. We identify the observable depicting mode decomposition, and using the freedom of operator ordering ambiguity, we obtain the Hermitian extension of this operator alongside the Hermitian Hamiltonian. After identifying incoming and outgoing modes with this operator’s eigenstates, we estimate their contributions to the radiation profile. True to a quantum description, the expanding and contracting branches do not entirely comprise of outgoing and incoming radiation. The infrared sector of this process demonstrates some characteristic features which turn out to be highly sensitive to the near-bounce dynamics of the dust cloud. Near the epoch of classical singularity, there is a significant contribution from incoming/outgoing modes of small wave number in the expanding/collapsing phase of the dust cloud, which keeps on decreasing as one moves away from the singularity. The information of the bounce is carried over to the infrared modes through a flip from largely incoming to largely outgoing radiation as the evolution progresses from collapsing to expanding phase, much before the information of bounce comes about to any observer. In the infrared sector, the saturation value of the amplitude marks the bounce radius. Thus, we argue that the information of the short scale physics is essentially carried over to the longest wavelength in this quantum gravity model, which we argue is rather more prominent for low energy processes.

We show that constraints on scalar field potentials and towers of light massive states in asymptotic limits of scalar field space (as posited by the de Sitter conjecture and the swampland distance conjecture, respectively) are correlated with the prospects for defining asymptotic observables in expanding Friedmann-Robertson-Walker cosmologies. The observations of a “census taker” in an eternally inflating cosmology are further related to the question of whether certain domain walls satisfy a version of the weak gravity conjecture. This suggests that answers to fundamental questions about asymptotic observables in cosmology could help shed light on the swampland program, and vice versa.

We construct monopole operators for 3D Yang-Mills matter theories and Chern-Simons matter theories in canonical formalism. In this framework, monopole operators, although they are disorder operators, could be written in terms of the fundamental fields of the theory, and thus could be treated in the same way as the ordinary operators. We study the properties of the constructed monopole operators. In Chern-Simons matter theories, monopole operators transform as the local operators with the classical conformal dimension 0 under the action of the dilation and are also covariantly constant. In supersymmetric Chern-Simons matter theories like the ABJM model, monopole operators commute with all of the supercharges, and thus are SUSY invariant. The ABJM model with level $k=1,2$ is expected to have enhanced $SO(8)$ R symmetry due to the existence of the conserved extra R-symmetry currents $j_{\mu }^{AB}$ involving monopoles. With the explicit form of the monopole operators given, we prove the current conservation equation ${\partial }^{\mu }{j}_{\mu }^{AB}=0$ using the equations of motion. We also compute the extra $\mathcal{N}=2$ supercharges, derive the extra $\mathcal{N}=2$ SUSY transformation rules, and verify the closure of the $\mathcal{N}=8$ supersymmetry.

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-Lemaître-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 both to hold simultaneously allows only for a very restricted class of geometries. For the general case, we derive the energy-momentum-hypermomentum conservation relations and the cosmological dynamics of selected symmetric teleparallel gravity theories. Our results show that the symmetric teleparallel connection in general contributes another scalar quantity into the cosmological dynamics, which decouples only for a specific class of theories from the dynamics of the metric, and only if the simplest geometry is chosen, in which both assumed coordinate systems agree. Most notably, the $f(Q)$ class of theories falls into this class.

The generalized hybrid metric-Palatini gravity is a theory of gravitation that has an action composed of a Lagrangian given by $f(R,\mathcal{R})$, where $f$ is a function of the metric Ricci scalar $R$ and a new Ricci scalar $\mathcal{R}$ formed from a Palatini connection, plus a matter Lagrangian. This theory can be rewritten by trading the new geometric degrees of freedom that appear in $f(R,\mathcal{R})$ into two scalar fields, $\phi$ and $\psi$, yielding a dynamically equivalent scalar-tensor theory. Given a spacetime theory, the next important step is to find solutions within it. To construct appropriate solutions it is often necessary to know the junction conditions between two spacetime regions at a separation hypersurface $\mathrm{\Sigma }$, with each spacetime region being an independent solution of the theory. The junction conditions for the generalized hybrid metric-Palatini gravity are found here, both in the geometric representation and in the scalar-tensor representation, and in addition, for each representation, the junction conditions for a matching with a thin-shell of matter and for a smooth matching at the separation hypersurface are worked out. These junction conditions are then applied to three configurations, namely, a star, a quasistar with a black hole, and a wormhole. The star is made of a Minkowski interior, a thin shell at the interface with all the matter energy conditions being satisfied, and a Schwarzschild exterior with mass $M$, and unlike general relativity where the matching can be performed at any radius $r_{\mathrm{\Sigma }}$, for this theory the matching can only be performed at a specific value of the shell radius, namely $r_{\mathrm{\Sigma }}=\frac{9M}{4}$, that corresponds to the general relativistic Buchdahl radius. The quasistar with a black hole is made of an interior Schwarzschild black hole surrounded by a thick shell that matches smoothly to a mass $M$ Schwarzschild exterior at the light ring radius $r_{\mathrm{\Sigma }e}=3M$, and with the matter energy conditions being satisfied for the whole spacetime. The wormhole is made of some interior with matter that contains the throat, a thin shell at the interface, and a Schwarzschild-AdS exterior with mass $M$ and negative cosmological constant $\mathrm{\Lambda }$, with the matter null energy condition being obeyed everywhere within the wormhole.

We show that in anisotropic Hořava-Lifshitz gravity there is a well-defined wave zone where the physical degrees of freedom propagate according to a nonrelativistic linear evolution equation of high order in spatial derivatives, which reduces to the wave equation at low energy. This is so, provided the coupling parameters satisfy some restrictions which we study in detail. They are imposed to obtain a finite Arnowitt-Deser-Misner gravitational energy, which depends manifestly on the terms which break the Lorentz symmetry of the formulation. The analysis we perform is beyond the linearized approach and includes all high-order terms of the Hamiltonian potential.

In general relativity, the remnant object originating from an uncharged black hole merger is a Kerr black hole. This final state is reached through the emission of a late train of radiation known as the black hole ringdown. In linear perturbation theory around the final state, the ringdown morphology is described by a countably infinite set of damped sinusoids—the quasinormal modes—whose complex frequencies are solely determined by the final black hole’s mass and spin. Recent results advocate that ringdown waveforms from numerical relativity can be fully described from the peak of the strain onwards if quasinormal mode models with $N_{\max }=7$ overtones (beyond the fundamental mode) are used. In this work we extend this analysis to models with $N_{\max }\ge 7$ up to $N_{\max }=16$ overtones by exploring the parameter bias on the final mass and spin obtained by fitting the nonprecessing binary black hole simulations from the SXS catalog. To this aim, we have computed the spin weight $-2$ Kerr quasinormal mode frequencies and angular separation constants for the $(l=m=2,n=8,9)$ co- and counter-rotating overtones, which all approach a Schwarzschild algebraically special mode at low spins. We provide tables of the values obtained for these modes, which are in agreement with previous results. From the systematic variable-$N_{\max }$ analysis, we find that $N_{\max }\sim 6$ overtones are on average sufficient to model the ringdown from the peak of the strain, although about 21% of the cases studied require at least $N_{\max }\sim 12$ overtones to reach a comparable accuracy on the final state parameters. Considering the waveforms from an earlier or later point in time, we find that a very similar maximum accuracy can be reached in each case, occurring at a different number of overtones $N_{\max }$. We also provide new error estimates for the SXS waveforms based on the extrapolation and the resolution uncertainties of the gravitational wave strain, which dominate over the errors obtained from the quasilocal measures of the final mass and spin. Finally, we observe substantial instabilities on the best-fit amplitudes of the tones beyond the fundamental mode and the first overtone, that, nevertheless, do not impact significantly the mass and spin estimates.

The anticipated enhancements in detector sensitivity and the corresponding increase in the number of gravitational wave detections will make it possible to estimate parameters of compact binaries with greater accuracy [assuming general relativity (GR)], and also to carry out sharper tests of GR itself. Crucial to these procedures are accurate gravitational waveform models. The systematic errors of the models must stay below statistical errors to prevent biases in parameter estimation and to carry out meaningful tests of GR. Comparisons of the models against numerical relativity waveforms provide an excellent measure of systematic errors. A complementary approach is to use balance laws provided by Einstein’s equations to measure faithfulness of a candidate waveform against exact GR. Each balance law focuses on a physical observable and measures the accuracy of the candidate waveform vis a vis that observable. Therefore, this analysis can provide new physical insights into sources of errors. In this paper we focus on the angular momentum balance law, using post-Newtonian theory to calculate the initial angular momentum, surrogate fits to obtain the remnant spin, and waveforms from models to calculate the flux. For brevity of presentation we restrict ourselves to the waveform models IMRPhenomXPHM, NRSur7dq4,SEOBNRv4PHM, IMRPhenomPv2, and SEOBNRv3. The consistency check provided by the angular momentum balance law brings out the marked improvement in the passage from IMRPhenomPv2 to IMRPhenomXPHM and from SEOBNRv3 to SEOBNRv4PHM and shows that the most recent versions agree quite well with exact GR. For precessing systems, on the other hand, we find that there is room for further improvement, especially for the Phenom models.

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 $\gtrsim 2\sigma$ and an increased value for $H_0\sim 70–74\mathrm{km}/\mathrm{s}/\mathrm{Mpc}$, compatible with local measurements, without the inclusion of any prior on $H_0$. On the other hand, the inclusion of Planck data restricts the EDE contribution to an upper limit only at 95% C.L. For axEDE, the combination of Planck and ACT leads to constraints 30% weaker than with Planck alone, and there is no residual Hubble tension. On the other hand, NEDE is more strongly constrained in a $Planck+\mathrm{ACT}$ analysis, and the Hubble tension remains at $\sim 3\sigma$, illustrating the ability for CMB data to distinguish between different EDE models. We further explore the apparent inconsistency between the Planck and ACT data and find that it comes (mostly) from a slight tension between the temperature power spectrum at multipoles around $\sim 1000$ and $\sim 1500$. Finally, through a mock analysis of ACT data, we demonstrate that the preference for EDE is not driven by a lack of information at high $\ell$ when removing Planck data, and that a $\mathrm{\Lambda }$ cold dark matter fit to the fiducial EDE cosmology results in a significant bias on $\{H_0,{\omega }_{\mathrm{CDM}}\}$. More accurate measurements of the TT CMB power spectra above $\ell \sim 2500$ and EE between $\ell \sim 300–500$ will play a crucial role in differentiating between EDE models.

Improved measurement of the Cosmic Microwave Background (CMB) polarization from Planck allows a detailed study of reionization beyond the average optical depth. The lower value of the optical depth disfavors an early onset and an early completion of reionization in favor of a redshift range where different astrophysical probes provide sensible information on the sources of reionization and the status of the intergalactic medium. In this work we extend our previous study in which we constrained reionization by combining three different probes—CMB, UV luminosity density and neutral hydrogen fraction data [D. K. Hazra, D. Paoletti, F. Finelli, and G. F. Smoot, Phys. Rev. Lett. 125, 071301 (2020)]—in both treatment and data: we first allow variation in the UV source term varying the product of the efficiency of conversion of UV luminosity into ionizing photons and the escape fraction together with the reionization and cosmological parameters, and then we investigate the impact of a less conservative cut for the UV luminosity function. We find that the estimate for the efficiency is consistent within 95% C.L. with the fixed value we considered in our previous results and is mostly constrained by QHII data. We find that allowing the efficiency to vary does not affect significantly our results for the average optical depth for monotonic reionization histories, recovering $\tau =0.0519_{-0.0008}^{+0.0010}$ at 68% C.L., consistent with our previous studies. Using a less conservative cut for the UV luminosity function, we find $\tau =0.0541_{-0.0016}^{+0.0013}$ at 68% C.L., due to the faint end of the luminosity function in the data we use, that also prefers a larger contribution from higher redshifts.

The spherical Fourier-Bessel (SFB) decomposition is a natural choice for the radial/angular separation that allows extraction of cosmological information from large volume galaxy surveys, taking into account all wide-angle effects. In this paper we develop a SFB power spectrum estimator that allows the measurement of the largest angular and radial modes with the next generation of galaxy surveys. The code measures the pseudo-SFB power spectrum, and takes into account mask, selection function, pixel window, and shot noise. We show that the local average effect (or integral constraint) is significant only in the largest-scale mode, and we provide an analytical covariance matrix. By imposing boundary conditions at the minimum and maximum radius encompassing the survey volume, the estimator does not suffer from the numerical instabilities that have proven challenging for SFB analyses in the past. The estimator is demonstrated on simplified but realistic Roman-like, SPHEREx-like, and Euclid-like mask and selection functions. For intuition and validation, we also explore the SFB power spectrum in the Limber approximation. We release the associated public code written in julia.

We study the effects of prerecombination physics on the stochastic gravitational wave background (SGWB) anisotropies induced by the propagation of gravitons through the large-scale density perturbations and their cross-correlation with cosmic microwave background (CMB) temperature and $E$-mode polarization ones. As examples of early Universe extensions to the $\mathrm{\Lambda }$ cold dark matter model, we consider popular models featuring extra relativistic degrees of freedom, a massless nonminimally coupled scalar field, and an early dark energy component. Assuming the detection of a SGWB, we perform a Fisher analysis to assess in a quantitative way the capability of future gravitational wave interferometers (GWIs) in conjunction with a future large-scale CMB polarization experiment to constrain such variations. Our results show that the cross-correlation of CMB and SGWB anisotropies will help tighten the constraints obtained with CMB alone, with an improvement that significantly depends on the specific model as well as the maximum angular resolution of the GWIs, their designed sensitivity, and the amplitude $A_{*}$ of the monopole of the SGWB.

In environments such as core-collapse supernovae, neutron star mergers, or the early universe, where the neutrino fluxes can be extremely high, neutrino-neutrino interactions are appreciable and contribute substantially to their flavor evolution. Such a system of interacting neutrinos can be regarded as a quantum many-body system, and prospects for nontrivial quantum correlations, i.e., entanglement, developing in a gas of interacting neutrinos have been investigated previously. In this work, we uncover an intriguing connection between the entropy of entanglement of individual neutrinos with the rest of the ensemble, and the occurrence of spectral splits in the energy spectra of these neutrinos, which develop as a result of collective neutrino oscillations. In particular, for various types of neutrino spectra, we demonstrate that the entanglement entropy is highest for the neutrinos whose locations in the energy spectrum are closest to the spectral split(s). This trend demonstrates that the quantum entanglement is strongest among the neutrinos that are close to these splits, a behavior that seems to persist even as the size of the many-body system is increased.

Correlated magnetic noise in the form of Schumann resonances could introduce limitations to the gravitational-wave background searches of future Earth-based gravitational-wave detectors. We consider recorded magnetic activity at a candidate site for the Einstein Telescope, and forecast the necessary measures to ensure that magnetic contamination will not pose a threat to the science goals of this third-generation detector. In addition to global magnetic effects, we study local magnetic noise and the impact it might have on colocated interferometers. We express our results as upper limits on the coupling function of magnetic fields to the interferometer arms, implying that any larger values of magnetic coupling into the strain channel would lead to a reduction in the detectors’ sensitivity. For gravitational-wave background searches below $\sim 30\mathrm{Hz}$ it will be necessary for the Einstein Telescope magnetic isolation coupling to be two to four orders of magnitude better than that measured in the current Advanced LIGO and Virgo detectors.

In this work we study how $CPT$-odd Maxwell-Carroll-Field-Jackiw (MCFJ) electrodynamics as well as a dimension-5 extension of it affect the optical activity of continuous media. The starting point is dimension-3 MCFJ electrodynamics in matter whose modified Maxwell equations, permittivity tensor, and dispersion relations are recapitulated. Corresponding refractive indices are achieved in terms of the frequency and the vector-valued background field. For a purely timelike background, the refractive indices are real. Their associated propagation modes are circularly polarized and exhibit birefringence. For a purely spacelike background, one refractive index is always real and the other can be complex. The circularly polarized propagating modes may exhibit birefringence and dichroism (associated with absorption). Subsequently, we examine a dimension-five MCFJ-type electrodynamics, previously scrutinized in the literature, in a continuous medium. Following the same procedure, we find the refractive indices from a sixth-order dispersion equation. For a purely timelike background, three distinct refractive indices are obtained, one of them being real and two being complex. They are associated with two circularly polarized propagating modes that exhibit birefringence or dichroism, depending on the frequency range. Scenarios of propagation and absorption analogous to those found in dispersive dielectrics are also observed for purely spacelike background configurations. We conclude by comparing the dimension-three and five results and by emphasizing the richer phenomenology of the propagating modes in the higher-derivative model. Our results are applicable in the realm of Weyl semimetals.

We study the properties of a hot and magnetized quark matter in a rotating cylinder in the presence of a constant magnetic field. To do this, we solve the corresponding Dirac equation using the Ritus eigenfunction method. This leads to the energy dispersion relation, Ritus eigenfunctions, and the quantization relation for magnetized fermions. To avoid causality-violating effects, we impose a certain global boundary condition and study its effect, in particular, on the energy eigenmodes and the quantization relations of fermions. Using the fermion propagator arising from this method, we then solve the gap equation at zero and nonzero temperatures. At zero temperature, the dynamical mass $\overline{m}$ does not depend on the angular frequency, as expected. We thus study its dependence on the distance $r$ relative to the axis of rotation and the magnetic field $B$ and explore the corresponding finite size effect for various couplings $G$. We then consider the finite temperature case. The dependence of $\overline{m}$ on the temperature $T$, magnetic field $B$, angular frequency $\mathrm{\Omega }$, and distance $r$ for various $G$ is studied. We show that $\overline{m}$ decreases, in general, with $B$ and $\mathrm{\Omega }$. This is the “inverse magnetorotational catalysis (IMRC)” or the “rotational magnetic inhibition”, previously discussed in the literature. To explore the evidence of this effect in the phase diagrams of our model, we examine the phase portraits of the critical temperature $T_c$ as well as the critical angular frequency ${\mathrm{\Omega }}_c$ with respect to $G$, $B$, $\mathrm{\Omega }$, and $r$ as well as $G$, $B$, $T$, and $r$, respectively. We show that $T_c$ and ${\mathrm{\Omega }}_c$ decrease, in particular, with $B$. This is interpreted as clear evidence for IMRC.