We consider a strongly coupled field theory with a critical point and a nonzero chemical potential at a finite temperature, which is dual to an asymptotically anti–de Sitter charged black hole. We study the evolution of the rescaled holographic subregion complexity near to and far from the critical point. We explain two distinct concepts of complexity in this theory and discuss that the state under study is complex based on how much information is needed to specify the state and is simple according to how many operations have to be done to reach the state. We justify the decreasing of the rescaled holographic subregion complexity with time using an increasing number of microstates of the mixed state and speculate about the description of the relative rescaled holographic subregion complexity of the initial state and the final state as a resource. We propose that in this process the complexity of the mixed state decreases and the complexity of the environment increases. We also observe that in this model the rescaled holographic subregion complexity is a good observable for probing the dynamical critical exponent.

We investigate the ultimate estimation precision, characterized by the quantum Fisher information, of a two-level atom as a detector which is coupled to massless scalar field in the Minkowski vacuum. It has been shown that for an inertial detector moving with a constant velocity, its quantum Fisher information is completely unaffected by the velocity, however, it still decays over time due to the decoherence caused by the interaction between the atom and the field. In addition, for a uniformly accelerated detector ($w=0$) moving along spatially straight line, the accelerated motion will reduce the quantum Fisher information in the estimation of state parameters. However, when the detector trajectory is generated by a combination of the linear accelerated motion and a component of the four-velocity $w=dy/d\tau$, we find quite unlike the previous results that, for the nonrelativistic case ($w\ll 1$), the acceleration could degrade the quantum Fisher information, while the four-velocity component will suppress the degradation of the quantum Fisher information, and thus could enhance the precision of parameters estimation. Furthermore, in the case for ultrarelativistic velocities $(w\to \infty )$, although the detector still interacts with the environment, it behaves as if it were a closed system as a consequence of relativity correction associated to the velocity, and the quantum Fisher information in this case can be shielded from the effect of the external environment, and thus from the relativistic motion.

We go beyond a systematic review of the semiclassical approaches for determining the scaling dimensions of fixed-charge operators in $U(1)$ and $O(N)$ models by introducing a general strategy apt at determining the relation between a given charge configuration and the associated operators for more involved symmetry groups such as the $U(N)\times U(M)$. We show how, varying the charge configuration, it is possible to access anomalous dimensions of different operators transforming according to a variety of irreducible representations of the non-Abelian symmetry group without the aid of diagrammatical computations. We illustrate our computational strategy by determining the anomalous dimensions of several composite operators to the next-to-leading order in the semiclassical expansion for the $U(N)\times U(M)$ conformal field theory (CFT) in $4-\epsilon$ dimensions. Thanks to the powerful interplay between semiclassical methods and group theory we can, for the first time, extract scaling dimensions for a wide range of operators.

The ability to test general relativity in extreme gravity regimes using gravitational wave observations from current ground-based or future space-based detectors motivates the mathematical study of the symmetries of black holes in modified theories of gravity. In this paper we focus on spinning black hole solutions in two quadratic gravity theories: dynamical Chern-Simons and scalar Gauss-Bonnet gravity. We compute the principal null directions, Weyl scalars, and complex null tetrad in the small-coupling, slow rotation approximation for both theories, confirming that both spacetimes are Petrov type I. Additionally, we solve the Killing equation through rank 6 in dynamical Chern-Simons gravity and rank 2 in scalar Gauss-Bonnet gravity, showing that there is no nontrivial Killing tensor through those ranks for each theory. We therefore conjecture that the still-unknown, exact, quadratic-gravity, black-hole solutions do not possess a fourth constant of motion.

We apply a recently developed $2+1+1$ decomposition of spacetime, based on a nonorthogonal double foliation for the study of spherically symmetric, static black hole solutions of Horndeski scalar-tensor theory. Our discussion proceeds in an effective field theory (EFT) of modified gravity approach, with the action depending on metric and embedding scalars adapted to the nonorthogonal $2+1+1$ decomposition. We prove that the most generic class of Horndeski Lagrangians compatible with observations can be expressed in this EFT form. By studying the first order perturbation of the EFT action we derive three equations of motion, which reduce to those derived earlier in an orthogonal $2+1+1$ decomposition, and a fourth equation for the metric parameter $\mathcal{N}$ related to the nonorthogonality of the foliation. For the Horndeski class of theories with vanishing $G_3$ and $G_5$, but generic functions $G_2(\varphi ,X)$ (k-essence) and $G_4(\varphi )$ (nonminimal coupling to the metric) we prove the unicity theorem that no action beyond Einstein-Hilbert allows for the Schwarzschild solution. Next we integrate the EFT field equations for the case with only one independent metric function, and we obtain new solutions characterized by a parameter, which in the simplest cases has the interpretation of mass or tidal charge, the cosmological constant and a third parameter. These solutions represent naked singularities, black holes with scalar hair or have the double horizon structure of the Schwarzschild–de Sitter spacetime. Solutions with homogeneous Kantowski-Sachs type regions also emerge. Finally, one of the solutions obtained for the function $G_4$ linear in the curvature coordinate, in certain parameter range exhibits an intriguing logarithmic singularity lying outside the horizon. The newly derived hairy black hole solutions evade previously known unicity theorems by being asymptotically nonflat, even in the absence of the cosmological constant.

We carry out numerical simulations of the gravitational collapse of a perfect fluid with the ultrarelativistic equation of state $P=\kappa \rho$, in spherical symmetry in $2+1$ spacetime dimensions with $\mathrm{\Lambda }<0$. At the threshold of prompt collapse, we find type II critical phenomena (apparent horizon mass and maximum curvature scale as powers of distance from the threshold) for $\kappa \gtrsim 0.43$, and type I critical phenomena (lifetime scales as logarithm of distance from the threshold) for $\kappa \lesssim 0.42$. The type I critical solution is static, while the type II critical solution is not self-similar (as in higher dimensions), but contracting quasistatically.

We write the field equations of torsion gravity theories and the Noether identity they obey directly in terms of metric and contorsion tensor components expressed with respect to natural coordinates, i.e., without using vierbien but Lagrange multipliers. Then we obtain explicit solutions of these equations, under specific ansätze for the contorsion field, by assuming the metric to be respectively of the Bertotti-Robinson, pp-wave, Friedmann-Lemaître-Robertson-Walker or static spherically symmetric type. Among these various solutions we obtain some of them have their contorsion tensor depending on arbitrary functions that did not influence their geometry. This raises questions about the predictability of the theory.

We investigate the effect of the population III (Pop III) stars supernova explosion (SN) on the high redshifts reionization history using the latest Planck data. It is predicted that massive Pop III stars $(130M_{\odot }\le M\le 270M_{\odot })$ explode energetically at the end of their stellar life as pair-instability supernovae (PISNe). In the explosion, supernova remnants grow as hot ionized bubbles and enhance the ionization fraction in the early stage of the reionization history. This enhancement affects the optical depth of the cosmic microwave background (CMB) and generates the additional anisotropy of the CMB polarization on large scales. Therefore, analyzing the Planck polarization data allows us to examine the Pop III star SNe and the abundance of their progenitors, massive Pop III stars. In order to model the supernova(SN) contribution to reionization, we introduce a new parameter $\zeta$, which relates to the abundance of the SNe to the collapse fraction of the Universe. Using the Markov chain Monte Carlo method with the latest Planck polarization data, we obtain the constraint on our model parameter, $\zeta$. Our constraint tells us that observed CMB polarization is consistent with the abundance of PISNe predicted from the star formation rate and initial mass function of Pop III stars in recent cosmological simulations. We also suggest that combining further observations on the late reionization history, such as high redshift quasi-stellar object (QSO) observations, can provide tighter constraints and important information on the nature of Pop III stars.

The axion-electron coupling $g_{ae}$ is a generic feature of nonhadronic axion models. This coupling may induce a variety of observable signatures, particularly in astrophysical environments. Here, we revisit the calculation of the axion-electron bremsstrahlung and provide a general formulation valid for a nonrelativistic plasma with any level of degeneracy and for any axion mass. We apply our result to the Sun, red giant stars, and white dwarfs. In particular, we prove that the approximations used to evaluate the axion emissivity in red giants agree with the exact result within 10%, comparable with other uncertainties in these studies. In addition, this prescription allows the red giant and white dwarf bounds to be extended to massive axions.

We introduce a generic algorithm to determine the time delays and spacecraft positions to compose any time-delay interferometry (TDI) channel in the dynamical case and evaluate its sensitivity by using a full numerical method. We select 11 second-generation TDI channels constructed from four approaches and investigate their gravitational wave responses, noise levels, and averaged sensitivities under a numerical LISA orbit. The sensitivities of selected channels are various especially for frequencies lower than 20 mHz. The optimal channel ${\mathrm{A}}_2$ (or equivalently ${\mathrm{E}}_2$) combined from second-generation Michelson TDI channels (${\mathrm{X}}_1$, ${\mathrm{X}}_2$, and ${\mathrm{X}}_3$) achieves the best sensitivity among the channels, while the Sagnac ${\alpha }_1$ channel shows the worst sensitivity. Multiple channels show better sensitivities at some characteristic frequencies compared to the fiducial ${\mathrm{X}}_1$ channel. The joint ${\mathrm{A}}_2+{\mathrm{E}}_2+{\mathrm{T}}_2$ observation not only enhances the sensitivity of the ${\mathrm{X}}_1$ channel by a factor of $\sqrt{2}$ to 2, but also improves the capacity of sky coverage.

Detecting axionic dark matter induced electron or nucleon oscillating electric dipole moment (OEDM) has become a new way for dark matter searches. We reexamine such axion-spin couplings in external electromagnetic fields. We point out that axion-photon interaction induces an electron spin effective coupling, which is different from an OEDM. In particular, the axion-spin effective coupling is directly related to magnetic field rather than electric field. For axion-electron or axion-nucleon couplings, an OEDM of fermion is introduced, whose effect in ultralight axion cases depends on whether axion shift symmetry is manifest. Specifically, ultralight axionic dark matter interactions that do not obey the shift symmetry will be strongly constrained. We also extend the results to the case where axion has a finite velocity.

We consider the production of a Higgs boson in association with two electroweak vector bosons at hadron colliders. In particular, we examine $\gamma \gamma H$, $\gamma ZH$, $ZZH$, and $W^{+}{W}^{-}H$ production at the LHC (14 TeV), HE-LHC (27 TeV), and FCC-hh (100 TeV) colliders. Our main focus is to estimate the gluon-gluon ($gg$) channel ($gg\to V{V}^{\prime }H$) contributions to $pp\to V{V}^{\prime }H(V,V^{\prime }=\gamma ,Z,W)$ and compare them with corresponding contributions arising from the quark-quark ($qq$) channel ($q\overline{q}\to V{V}^{\prime }H$). Technically, the leading order $gg$ channel contribution to the $pp\to V{V}^{\prime }H$ cross section is a next-to-next-to-leading order correction in the strong coupling parameter, ${\alpha }_s$. In the processes under consideration, we find that in the $gg$ channel, $W^{+}{W}^{-}H$ has the largest cross section. However, the relative contribution of the $gg$ channel is more important for the $pp\to ZZH$ production. At the FCC-hh, the $gg\to ZZH$ contribution is comparable with the next-to-leading order QCD correction to $qq\to ZZH$. We also compute the cross sections when $W$ and $Z$ bosons are polarized. In the production of $W^{+}{W}^{-}H$ and $ZZH$, we find that the $gg$ channel contributes more significantly when the vector bosons are longitudinally polarized. By examining such events, one can increase the fraction of the $gg$ channel contribution to these processes. Further, we have studied beyond-the-standard-model effects in these processes using the $\kappa$-framework parameters ${\kappa }_t$, ${\kappa }_V$, and ${\kappa }_{\lambda }$. We find that the $gg$ channel processes $ZZH$ and $WWH$ have a very mild dependence on ${\kappa }_{\lambda }$, but strong dependence on ${\kappa }_t$ and ${\kappa }_V$. The $qq$ channel processes mainly depend on ${\kappa }_V$. Dependence of the $gg$ channel contribution on ${\kappa }_V$ is stronger than that of the $qq$ channel contribution. Therefore, focusing on events with longitudinally polarized $W$ and $Z$ bosons, one can find stronger dependence on ${\kappa }_V$ that can help us measure this parameter.

We perform a comprehensive and model-independent analysis for characterizing the spin and dynamical structure of the production of a nondiagonal pair of Majorana particles with different masses and arbitrary spins $e^{-}{e}^{+}\to X_2{X}_1$, followed by a sequential two-body decay $X_2\to Z{X}_1$ of the heavier particle $X_2$ into a $Z$ gauge boson and the lighter particle $X_1$ escaping undetected at high-energy $e^{+}{e}^{-}$ colliders. Standard leptonic $Z$-boson decays, $Z\to {\ell }^{-}{\ell }^{+}$ with $\ell =e$ or $\mu$, are employed for precisely diagnosing the $Z$ polarization influenced by the production and decay processes. Based on helicity formalism and Wick helicity rotation for describing the correlated production-decay amplitudes and distributions, we work out the implications on the amplitudes and distributions of discrete $CP$ symmetry and the Majorana condition that two particles are their own antiparticles. For the sake of a concrete illustration, an example of this type in the minimal supersymmetric Standard Model is investigated in detail.

We study the three-dimensional lens partition function for $\mathcal{N}=2$ supersymmetric gauge dual theories on $S^3/{\mathbb{Z}}_r$ by using the gauge/Yang-Baxter equation correspondence. This correspondence relates supersymmetric gauge theories to exactly solvable models of statistical mechanics. The equality of partition functions for the three-dimensional supersymmetric dual theories can be written as an integral identity for hyperbolic hypergeometric functions. We obtain such an integral identity which can be written as the star-triangle relation for Ising type integrable models and as the integral pentagon identity. The latter represents the basic 2-3 Pachner move for triangulated 3-manifolds. A special case of our integral identity can be used for proving orthogonality and completeness relation of the Clebsch-Gordan coefficients for the self-dual continuous series of $U_q(osp(1|2))$.

Harvesting the full potential of black hole spectroscopy demands realizing the importance of casting constraints on modified theories of gravity in a framework as general and robust as possible. Requiring more stringent—yet well motivated—beyond–general relativity (GR) parametrizations improves the inference drawn from available GW data, substantially decreasing the errors on deviation parameters. This implies a reduction in the number of signals needed to detect a deviation from GR predictions and an increase of the number of GR-violating coefficients that can be meaningfully constrained with a given number of signals. To this end, we apply to LIGO-Virgo observations a high-spin version of the parametrized ringdown spin expansion coefficients formalism, encompassing large classes of modified theories of gravity. We constrain the lowest-order perturbative deviation of the fundamental ringdown frequency to be $\delta {\omega }_{220}^0={-0.05}_{-0.05}^{+0.05}$, when assuming adimensional beyond-GR couplings, substantially improving upon previously published results. We also establish upper bounds ${\ell }_{p=2}<23\mathrm{km}$, ${\ell }_{p=4}<35\mathrm{km}$, ${\ell }_{p=6}<42\mathrm{km}$ on the scale ${\ell }_p$ at which the appearance of new physics is disfavored, depending on the mass dimension $p$ of the ringdown coupling. These bounds exceed the ones obtained by previous analyses or are competitive with existing ones, depending on the specific alternative theory considered, and promise to quickly improve as the number of detectors, sensitivity, and duty cycle of the gravitational-wave network steadily increases.

We revisit the impact of early dark energy (EDE) on galaxy clustering using BOSS galaxy power spectra, analyzed using the effective field theory (EFT) of large-scale structure (LSS) and anisotropies of the cosmic microwave background (CMB) from Planck. Recent studies found that these data place stringent constraints on the maximum abundance of EDE allowed in the Universe. We argue here that their conclusions are a consequence of their choice of priors on the EDE parameter space, rather than any disagreement between the data and the model. For example, when considering EFT-LSS, CMB, and high-redshift supernovae data we find the EDE and $\mathrm{\Lambda }\mathrm{CDM}$ models can provide statistically indistinguishable fits ($\mathrm{\Delta }{\chi }^2=0.12$) with a relatively large value for the maximum fraction of energy density in the EDE ($f_{\mathrm{ede}}=0.09$) and Hubble constant ($H_0=71\mathrm{km}/\mathrm{s}/\mathrm{Mpc}$) in the EDE model. Moreover, we demonstrate that the constraining power added from the inclusion of EFT-LSS traces to the potential tension between the power-spectrum amplitudes $A_s$ derived from BOSS and from Planck that arises even within the context of $\mathrm{\Lambda }\mathrm{CDM}$. Until this is better understood, caution should be used when interpreting $\mathrm{EFT}\text{−}\mathrm{BOSS}+Planck$ constraints to models beyond $\mathrm{\Lambda }\mathrm{CDM}$. These findings suggest that EDE still provides a potential resolution to the Hubble tension and that it is worthwhile to test the predictions of EDE with future datasets and further study its theoretical possibilities.

Leptonic CP violation search, neutrino mass hierarchy determination, and the precision measurements of oscillation parameters for a unitary test of the leptonic mixing matrix are among the major targets of the ongoing and future neutrino oscillation experiments. The work explores the physics reach for these targets by around 2027, when the third generation of the neutrino experiments starts operation, with a combined sensitivity of three experiments: T2K-II, $\mathrm{NO}\nu \mathrm{A}$ extension, and JUNO. It is shown that a joint analysis of these three experiments can conclusively determine the neutrino mass hierarchy. Also, at certain values of true ${\delta }_{CP}$, it provides closely around a $5\sigma$ confidence level (C.L.) to exclude $CP$-conserving values and more than a 50% fractional region of true ${\delta }_{CP}$ values can be explored with a statistic significance of at least a $3\sigma$ C.L. Besides, the joint analysis can provide unprecedented precision measurements of the atmospheric neutrino oscillation parameters and a great offer to solve the ${\theta }_{23}$ octant degeneracy in the case of nonmaximal mixing.

A search for the charged lepton flavor violating decay $J/\psi \to e^{\pm }{\tau }^{\mp }$ with ${\tau }^{\mp }\to {\pi }^{\mp }{\pi }^0{\nu }_{\tau }$ is performed with about $10\times {10}^{9}J/\psi$ events collected with the BESIII detector at the BEPCII. No significant signal is observed, and an upper limit is set on the branching fraction $\mathcal{B}(J/\psi \to e^{\pm }{\tau }^{\mp })<7.5\times {10}^{-8}$ at the 90% confidence level. This improves the previously published limit by two orders of magnitude.

In three dimensions, there are two types of $\mathcal{N}=2$ anti–de Sitter (AdS) supersymmetry, which are denoted (1, 1) and (2, 0). They are characterized by different supercurrents and support different families of higher-spin gauge models (massless and massive), which were constructed in Hutomo et al. [$\mathcal{N}=2$ supersymmetric higher spin gauge theories and current multiplets in three dimensions, Phys. Rev. D 98, 125004 (2018); Higher spin supermultiplets in three dimensions: (2, 0) AdS supersymmetry, Phys. Lett. B 787, 175 (2018)] for the (1, 1) and (2, 0) cases, respectively, using superspace techniques. It turns out that the precise difference between the (1, 1) and (2, 0) higher-spin supermultiplets can be pinned down by reducing these gauge theories to (1, 0) AdS superspace. The present paper is devoted to the $(1,1)\to (1,0)$ AdS superspace reduction. In conjunction with the outcomes of the $(2,0)\to (1,0)$ AdS superspace reduction carried out in Hutomo and Kuzenko [Field theories with (2, 0) AdS supersymmetry in $\mathcal{N}=1$ AdS superspace, Phys. Rev. D 100, 045010 (2019)], we demonstrate that every known higher-spin theory with (1, 1) or (2, 0) AdS supersymmetry decomposes into a sum of two off-shell (1, 0) supermultiplets that belong to four series of inequivalent higher-spin gauge models. The latter are reduced to components.

We investigate whether a class of models describing F-theory compactifications admits a specific type of flux vacua with an exponentially small vacuum expectation value of the superpotential, by generalizing a method recently developed in type IIB flux compactifications. First we clarify that a restricted choice of $G_4$-flux components reduces a general flux superpotential into a simple form, which promotes the existence of supersymmetric vacua with one flat direction at the perturbative level. Then we utilize the techniques of mirror symmetry to determine one-instanton corrections to the potential and investigate in detail the vacuum solutions of a particular model.