We argue that the detection of the neutrino signature from the Earth’s core can effectively probe the coupling of heavy dark matter ($m_{\chi }>{10}^4\mathrm{GeV}$) to nucleons. We first note that direct searches for dark matter (DM) in such a mass range provide much less stringent constraint than the constraint provided by such searches for $m_{\chi }\sim 100\mathrm{GeV}$. Furthermore, the energies of neutrinos arising from DM annihilation inside the Sun cannot exceed a few TeVs at the Sun’s surface due to the attenuation effect. Therefore, the sensitivity to the heavy DM coupling is lost. Finally, the detection of the neutrino signature from the Galactic halo can only probe DM annihilation cross sections. We present neutrino event rates in IceCube and KM3NeT arising from the neutrino flux produced by annihilation of Earth-captured DM heavier than ${10}^4\mathrm{GeV}$. The IceCube and KM3NeT sensitivities to spin-independent DM-proton scattering cross section ${\sigma }_{\chi p}$ in this mass range are presented for both isospin-symmetric and isospin-violating cases.

Using data samples collected at center-of-mass energies $\sqrt{s}=4.23$, 4.26, and 4.36 GeV with the BESIII detector operating at the BEPCII storage ring, we search for the production of the charmoniumlike state $Y(4140)$ through a radiative transition followed by its decay to $\varphi J/\psi$. No significant signal is observed and upper limits on $\sigma [e^{+}{e}^{-}\to \gamma Y(4140)]·\mathcal{B}(Y(4140)\to \varphi J/\psi )$ at the 90% confidence level are estimated as 0.35, 0.28, and 0.33 pb at $\sqrt{s}=4.23$, 4.26, and 4.36 GeV, respectively.

We derive the equations of motion for a system undergoing boost-invariant longitudinal and azimuthally symmetric transverse “Gubser flow” using leading-order anisotropic hydrodynamics. This is accomplished by assuming that the one-particle distribution function is ellipsoidally symmetric in the momenta conjugate to the de Sitter coordinates used to parametrize the Gubser flow. We then demonstrate that the $SO(3{)}_q$ symmetry in de Sitter space further constrains the anisotropy tensor to be of spheroidal form. The resulting system of two coupled ordinary differential equations for the de Sitter-space momentum scale and anisotropy parameter are solved numerically and compared to a recently obtained exact solution of the relaxation-time-approximation Boltzmann equation subject to the same flow. We show that anisotropic hydrodynamics describes the spatiotemporal evolution of the system better than all currently known dissipative hydrodynamics approaches. In addition, we prove that anisotropic hydrodynamics gives the exact solution of the relaxation-time approximation Boltzmann equation in the ideal, $\eta /s\to 0$, and free-streaming, $\eta /s\to \infty$, limits.

We explore a technique recently proposed in [1] and suggest a correspondence between the $N$-point correlation functions on a conifold and the $(N+1)$-point correlation functions on a regular manifold. This correspondence suggests a new systematic way to evaluate the correlation functions on a manifold with conical defect. We apply the correspondence to study the vacuum expectation value of a scalar operator and of the energy-momentum tensor in a conformal field theory living on a spacetime with conical singularity. Our findings agree with the existing calculations for a cosmic string spacetime. We use the correspondence to carry out calculations for the generic scalar operator and conserved vector current. For a unitary field theory we also compute the expectation value of the energy-momentum tensor using the spectral representation of a two-point function of the energy-momentum tensor in Minkowski spacetime.

We study moduli fields that arise in string/supergravity models in the context of the inflationary scenario. The early time cosmological dynamics involves generation of density perturbations by quantum fluctuations of the inflaton; the late time dynamics involves a modulus field dominating the energy density of the Universe and then its decay. We derive a relation which relates the modulus mass, inflationary observables and broad features of the reheating epoch. When viewed along with generic expectations regarding reheating and the initial field displacement of the modulus after inflation, this gives a bound on the modulus mass. For a large class of models, the bound is much stronger than the cosmological moduli problem bound.

The propagators of the elementary degrees of freedom of (minimal-)Landau-gauge Yang-Mills theory have been a useful tool in various investigations. However, in lattice calculations they show severe dependencies on lattice artifacts. This problem has been addressed for various subsets of lattice artifacts and various subsets of propagators over time. Here, an extended study of all propagators in momentum space, and for the gluon also in position space, as well as derived quantities like the running coupling, is provided simultaneously for two, three, and four dimensions over one or more orders of magnitude in both physical volume and lattice spacing, in lower dimensions also over more than 2 orders of magnitude for the gauge group SU(2). Most of the known qualitative results are confirmed, but two quantities also indicate a slight, but possibly interesting deviation.

We extend the results of our previous work on the conformal invariant description of two relativistic point particles. We consider here the most general Lagrangian by using a conformal tensor $h_{\mu \nu }$, transforming as a Wilson line, which allows us to construct invariant expressions for velocities taken at two different space-time points.

In this second part of our investigation [1] of the analytic structure of the $2\to 5$ scattering amplitude in the planar limit of $\mathcal{N}=4$ super Yang-Mills theory in multi-Regge kinematics we compute, in all kinematic regions, the Regge-cut contributions at leading order. The results are infrared finite and conformally invariant.

We calculate the ultraviolet to infrared evolution and analyze possible types of infrared behavior for several asymptotically free chiral gauge theories with gauge group $\mathrm{SU}(N)$ and massless chiral fermions transforming according to a symmetric rank-2 tensor representation $S$ and $N+4$ copies (flavors) of a conjugate fundamental representation $\overline{F}$, together with a vectorlike subsector with chiral fermions in higher-dimensional representation(s). We construct and study three such chiral gauge theories. These have respective vectorlike subsectors comprised of (a) $p$ copies of fermions in the adjoint representation, (b) $N=2k$ even and $p$ copies of fermions in the antisymmetric rank-$k$ tensor representation, and (c) $p$ copies of $\{S+\overline{S}\}$ fermions. Results are presented for beta functions, their infrared zeros, and predictions from the most-attractive-channel approach for the formation of bilinear fermion condensates. Importantly, we show that for these theories, the expected ultraviolet to infrared evolution obeys a conjectured inequality concerning the field degrees of freedom for all values of the parameters $N$ and $p$ characterizing each theory.

We construct an equation of state for massive neutron stars based on quantum chromodynamics phenomenology. Our primary purpose is to delineate the relevant ingredients of equations of state that simultaneously have the required stiffness and satisfy constraints from thermodynamics and causality. These ingredients are (i) a repulsive density-density interaction, universal for all flavors, (ii) the color-magnetic interaction active from low to high densities, (iii) confining effects, which become increasingly important as the baryon density decreases, and (iv) nonperturbative gluons, which are not very sensitive to changes of the quark density. We use the following “3-window” description: At baryon densities below about twice normal nuclear density, $2n_0$, we use the Akmal-Pandharipande-Ravenhall (APR) equation of state, and at high densities, $\ge (4-7)n_0$, we use the three-flavor Nambu-Jona-Lasinio (NJL) model supplemented by vector and diquark interactions. In the transition density region, we smoothly interpolate the hadronic and quark equations of state in the chemical potential-pressure plane. Requiring that the equation of state approach APR at low densities, we find that the quark pressure in nonconfining models can be larger than the hadronic pressure, unlike in conventional equations of state. We show that consistent equations of state of stiffness sufficient to allow massive neutron stars are reasonably tightly constrained, suggesting that gluon dynamics remains nonperturbative even at baryon densities $\sim 10n_0$.

We construct Born-Infeld (BI) type gravity theories which describe tree-level unitary (nonghost and nontachyonic) massless spin-2 modes around their maximally symmetric vacua in four dimensions. Building unitary BI actions around flat vacuum is straightforward, but this is a complicated task around (anti)-de Sitter backgrounds. In this work, we solve the issue and give details of constructing perturbatively viable determinantal BI theories. It is interesting that the Gauss-Bonnet combination, which is a total derivative in four dimensions, plays an important role in the construction of viable BI theories.

We revisit the small-field Coleman-Weinberg inflation, which has the following two problems: First, the smallness of the slow roll parameter $\epsilon$ requires the inflation scale to be very low. Second, the spectral index $n_s\approx 1+2\eta$ tends to become smaller compared to the observed value. In this paper, we consider two possible effects on the dynamics of inflation: radiatively generated nonminimal coupling to gravity $\xi {\varphi }^2\mathcal{R}$ and condensation of fermions coupled to the inflaton as $\varphi \overline{\psi }\psi$. We show that the fermion condensate can solve the above problems.

Stationary axisymmetric binary systems of unequal counterrotating Kerr-Newman sources with a massless strut in between are studied. By means of the choice of a suitable parametrization, the axis conditions and the absence of individual magnetic charges are fulfilled; thus, the entire metric reduces to a six-parametric asymptotically flat exact solution. Later on, with the purpose to describe interacting black holes, the analytic functional form of the horizon half-length parameter ${\sigma }_k$ is obtained explicitly in terms of physical Komar parameters: mass $M_k$, electric charge $Q_k$, angular momentum $J_k$, and coordinate distance $R$, where the seven physical parameters satisfy a simple algebraic relation. Finally, in the limit of extreme black holes, the full metric is derived in a closed analytical form, and a study on the absence or appearance of naked singularities off the axis is presented.

If a sizeable tensor-to-scalar ratio $\sim 0.1$ turns out to be detected and a negative running of the scalar spectral index $\sim {10}^{-2}$ is significantly required by the data, the vast majority of single field models of inflation will be ruled out. We show that a flat tree-level effective potential, lifted by radiative corrections and by the imprints of a high energy scale (in the form of nonrenormalizable operators) can explain those features and produce enough inflation in the slow-roll regime.

The two-point correlation function of the cosmic microwave background temperature anisotropies is generally assumed to be statistically isotropic (SI). Deviations from this assumption could be traced to physical or observational artifacts and systematic effects. Measurement of nonvanishing power in the bipolar spherical harmonic spectra is a standard statistical technique to search for isotropy violations. Although this is a neat tool allowing a blind search for SI violations in the cosmic microwave background sky, it is not easy to discern the cause of isotropy violation by using this measure. In this article, we propose a novel technique of constructing orthogonal bipolar spherical harmonic estimators, which can be used to discern between models of isotropy violation.

The most sensitive measurements of time and space are made with resonant optical cavities, and these measurements are limited by coating thermal noise. The mechanical and optical performance requirements placed on coating materials, especially for interferometric gravitational wave detectors, have proven extremely difficult to meet despite a lengthy search. In this paper we propose a new approach to high performance coatings, the use of multiple materials at different depths in the coating. To support this we generalize previous work on thermal noise in two-material coatings to an arbitrary multimaterial stack, and develop a means of estimating absorption in these multimaterial coatings. This new approach will allow for a broadening of the search for high performance coating materials.

Future gravitational wave detectors (GWDs) such as Advanced LIGO upgrades and the Einstein Telescope are planned to operate at cryogenic temperatures using crystalline silicon (cSi) test-mass mirrors at an operation wavelength of 1550 nm. The reduction in temperature in principle provides a direct reduction in coating thermal noise, but the presently used coating stacks which are composed of silica (${\mathrm{SiO}}_2$) and tantala (${\mathrm{Ta}}_2{\mathrm{O}}_5$) show cryogenic loss peaks which results in less thermal noise improvement than might be expected. Due to low mechanical loss at low temperature amorphous silicon (aSi) is a very promising candidate material for dielectric mirror coatings and could replace ${\mathrm{Ta}}_2{\mathrm{O}}_5$. Unfortunately, such an $\mathrm{aSi}/{\mathrm{SiO}}_2$ coating is not suitable for use in GWDs due to high optical absorption in aSi coatings. We explore the use of a three material based coating stack. In this multimaterial design the low absorbing ${\mathrm{Ta}}_2{\mathrm{O}}_5$ in the outermost coating layers significantly reduces the incident light power, while aSi is used only in the lower bilayers to maintain low optical absorption. Such a coating design would enable a reduction of Brownian thermal noise by 25%. We show experimentally that an optical absorption of only $(5.3\pm 0.4)\mathrm{ppm}$ at 1550 nm should be achievable.