We demonstrate that rapidity separated dihadron spectra in high multiplicity proton-proton collisions at the LHC can be quantitatively described by a combination of Balitsky-Fadin-Kuraev-Lipatov and saturation dynamics. Based on these results, we predict the systematics of dihadron spectra in proton-nucleus collisions at the LHC.

We investigate a family of inhomogeneous and anisotropic gravitational fields exhibiting a future singularity at a finite value of the proper time. The studied spherically symmetric spacetimes are asymptotically Friedmann-Robertson-Walker at spatial infinity and describe wormhole configurations filled with two matter components: one inhomogeneous and anisotropic fluid and another isotropic and homogeneously distributed fluid, characterized by the supernegative equation of state $\omega =p/\rho <-1$. In previously constructed wormholes, the notion of the phantom energy was used in a more extended sense than in cosmology, where the phantom energy is considered a homogeneously distributed fluid. Specifically, for some static wormhole geometries the phantom matter was considered as an inhomogeneous and anisotropic fluid, with radial and lateral pressures satisfying the relations $p_r/\rho <-1$ and $p_l\ne p_r$, respectively. In this paper we construct phantom evolving wormhole models filled with an isotropic and homogeneous component, described by a barotropic or viscous phantom energy, and ending in a big rip singularity. In two of considered cases the equation of state parameter is constrained to be less than $-1$, while in the third model the finite-time future singularity may occur for $\omega <-1$, as well as for $-1<\omega \le 1$.

We derive the conservative part of the Lagrangian and the energy of a gravitationally bound two-body system at fourth post-Newtonian order, up to terms quadratic in the Newton constant. We also show that such terms are compatible with Lorentz invariance and we write an ansatz for the center-of-mass position. The remaining terms carrying higher powers of the Newton constant are currently under investigation.

The retarded Green function of the wave equation for linear field perturbations in Schwarzschild black hole space-time possesses a branch cut in the complex-frequency plane. This branch cut has remained largely unexplored: only asymptotic analyses either for small frequency (yielding the well-known tail decay at late times of an initial perturbation of the black hole) or for large frequency (quasinormal modes close to the branch cut in this regime have been linked to quantum properties of black holes) have been carried out in the literature. The regime along the cut inaccessible to these asymptotic analyses has so far remained essentially unreachable. We present a new method for the analytic calculation of the branch cut directly on the cut for general-spin fields in Schwarzschild space-time. This method is valid for any values of the frequency and so it provides analytic access to the whole branch cut for the first time. We calculate the Green function modes along the cut and investigate their connection with quasinormal modes and their contribution to the self-force acting on a point particle on a Schwarzschild background space-time.

We study the contribution of the gluino-squark mediated flavor changing process for the $CP$ violation in $b\to s$ and $b\to d$ transitions taking account of recent experimental data. The mass insertion parameters of squarks are constrained by the branching ratios of $b\to s\gamma$ and $b\to d\gamma$ decays. In addition, the time-dependent $CP$ asymmetries of $B^0\to \varphi K_S$ and $B^0\to {\eta }^{\prime }{K}^0$ decays severely restrict the allowed region of the mass insertion parameter for the $b\to s$ transition. By using these constraints with squark and gluino masses of 1.5 TeV, we predict the $CP$ asymmetries of $B_s\to \varphi \varphi$, $B_s\to {\eta }^{\prime }\varphi$, and $B^0\to K^0{\overline{K}}^0$ decays, as well as the $CP$ asymmetries in $b\to s\gamma$ and $b\to d\gamma$ decays. The $CP$ violation in the $B_s\to \varphi \varphi$ decay is expected to be large owing to the squark flavor mixing, which will be tested at LHCb soon.

We investigate a way of circumventing the sign problem in lattice QCD simulations with a theta-vacuum term, using the Polyakov-loop extended Nambu–Jona-Lasinio model. We consider the reweighting method for the QCD Lagrangian after the $U_{\mathrm{A}}(1)$ transformation. In the Lagrangian, the $P$-odd mass term as a cause of the sign problem is minimized. In order to find a good reference system in the reweighting method, we estimate the average reweighting factor by using the two-flavor Polyakov-loop extended Nambu–Jona-Lasinio model and eventually find a good reference system.

The latest XENON100 data severely constrain dark matter elastic scattering off nuclei, leading to impressive upper limits on the spin-independent cross section. The main goal of this paper is to stress that the same data set has also an excellent spin-dependent sensitivity, which is of utmost importance in probing dark matter models. We show in particular that the constraints set by XENON100 on the spin-dependent neutron cross section are by far the best at present, whereas the corresponding spin-dependent proton limits lag behind other direct detection results. The effect of nuclear uncertainties on the structure functions of xenon isotopes is analyzed in detail and found to lessen the robustness of the constraints, especially for spin-dependent proton couplings. Notwithstanding, the spin-dependent neutron prospects for XENON1T and DARWIN are very encouraging. We apply our constraints to well-motivated dark matter models and demonstrate that in both mass-degenerate scenarios and the minimal supersymmetric standard model the spin-dependent neutron limits can actually override the spin-independent limits. This opens the possibility of probing additional unexplored regions of the dark matter parameter space with the next generation of ton-scale direct detection experiments.

In this work, we study the light stop pair signals at the Large Hadron Collider (LHC) in three coannihilation scenarios, where the neutralino can coannihilate with the stop, chargino and stau, respectively, so as to yield the desired dark matter relic density. Signatures of the first scenario can be probed at the LHC via the associated jet production processes $pp\to j+\tilde{t}{\tilde{t}}^{*}$ by tagging an energetic monojet and a large missing transverse energy. The signatures of the other two scenarios can be searched via the pair production process $pp\to \tilde{t}{\tilde{t}}^{*}$ by tagging energetic $b$ jets in the final states and a large missing transverse energy. We find that the LHC results at 7 TeV with $5{\mathrm{fb}}^{-1}$ of data can exclude the stop mass up to 220, 380, and 220 GeV for these three scenarios, respectively. While the $20{\mathrm{fb}}^{-1}$ data set at 8 TeV is considered, the LHC can be expected to exclude the stop mass up to 340, 430, and 370 GeV.

The importance of the $H\to ZZ\to 4\ell$ “golden” channel was shown by its major role in the discovery, by the ATLAS and CMS collaborations, of a Higgs-like boson with mass near 125 GeV. We analyze the discrimination power of the matrix element method both for separating the signal from the irreducible $ZZ$ background and for distinguishing various spin and parity hypotheses describing a signal in this channel. We show that the proper treatment of interference effects associated with permutations of identical leptons in the $4e$ and $4\mu$ final states plays an important role in achieving the best sensitivity in measuring the properties of the newly discovered boson. We provide a code, mekd, that calculates kinematic discriminants based on the full leading-order matrix elements and which will aid experimentalists and phenomenologists in their continuing studies of the $H\to ZZ\to 4\ell$ channel.

We have proposed the non-Abelian dual superconductivity picture for quark confinement in the $SU(3)$ Yang-Mills (YM) theory, and have given numerical evidences for the restricted-field dominance and the non-Abelian magnetic monopole dominance in the string tension by applying a new formulation of the YM theory on a lattice. To establish the non-Abelian dual superconductivity picture for quark confinement, we have observed the non-Abelian dual Meissner effect in the $SU(3)$ Yang-Mills theory by measuring the chromoelectric flux created by the quark-antiquark source, and the non-Abelian magnetic monopole currents induced around the flux. We conclude that the dual superconductivity of the $SU(3)$ Yang-Mills theory is strictly the type I and that this type of dual superconductivity is reproduced by the restricted field and the non-Abelian magnetic monopole part, in sharp contrast to the $SU(2)$ case: the border of type I and type II.

We use gauge/string duality to model some hybrid pseudopotentials in a pure $SU(N)$ gauge theory. The pseudopotentials under consideration can’t be described by a single Nambu-Goto string. This is why we call them “exotic”. A comparison with the calculation of the pseudopotential shows the universality of the spatial string tension.

Given recent indications of additional neutrino species and cosmologically significant neutrino masses, we analyze their signatures in the weak lensing shear power spectrum. We find that a shear deficit in the 20%–40% range or excess in the 20%–60% range cannot be explained by variations in parameters of the flat $\Lambda \mathrm{CDM}$ model that are allowed by current observations of the expansion history from Type Ia supernovae, baryon acoustic oscillations, and local measures of the Hubble constant $H_0$, coupled with observations of the cosmic microwave background from WMAP9 and the South Pole Telescope 2500 square degree survey. Hence such a shear deficit or excess would indicate large masses or extra species, respectively, and we find this to be independent of the flatness assumption. We also discuss the robustness of these predictions to cosmic acceleration physics and the means by which shear degeneracies in joint variation of mass and species can be broken.

An extra dark radiation component can be present in the universe in the form of sterile neutrinos, axions or other very light degrees of freedom which may interact with the dark matter sector. We derive here the cosmological constraints on the dark radiation abundance, on its effective velocity and on its viscosity parameter from current data in dark radiation-dark matter coupled models. The cosmological bounds on the number of extra dark radiation species do not change significantly when considering interacting schemes. We also find that the constraints on the dark radiation effective velocity are degraded by an order of magnitude while the errors on the viscosity parameter are a factor of two larger when considering interacting scenarios. If future Cosmic Microwave Background data are analyzed assuming a noninteracting model but the dark radiation and the dark matter sectors interact in nature, the reconstructed values for the effective velocity and for the viscosity parameter will be shifted from their standard $1/3$ expectation, namely $c_{\mathrm{eff}}^2={0.34}_{-0.003}^{+0.006}$ and $c_{\mathrm{vis}}^2={0.29}_{-0.001}^{+0.002}$ at 95% C.L. for the future COrE mission data.

We develop further a kinetic theory of strings and derive a transport equation for a network of cosmic strings with Nambu-Goto evolution, interactions, and background gravitational effects taken into account. We prove an $H$-theorem and obtain necessary and sufficient conditions for a thermodynamic equilibrium. At the lowest order, the equilibrium is estimated by the von Mises-Fisher distributions, parametrized by mean directions and dispersions of the right- and left-moving tangent vectors. Under assumption of a local equilibrium, we derive a complete set of hydrodynamic equations that govern the evolution of strings on large scales. We also argue that on small scales, the assumption of a local equilibrium would break down, so nonequilibrium steady states, described by the Sinai-Ruelle-Bowen distributions, should be used instead.

According to the AdS/CFT correspondence, the $\mathcal{N}=4$ supersymmetric Yang-Mills (SYM) theory has been studied by solving the dual supergravity. In solving the bulk Einstein equation, we find that it could be related to the 4D Friedmann equation, which is solved by using the cosmological constant and the energy density of the matter on the boundary, and they are dynamically decoupled from the SYM theory. We call this combination of the bulk Einstein equations and the 4D Friedmann equation as holographic Friedmann equations. Solving the holographic Friedmann equations, it is shown how the 4D decoupled matter and the cosmological constant control the dynamical properties of the SYM theory, quark confinement, chiral symmetry breaking, and baryon stability. From their effect on the SYM, the various kinds of matter are separated to two groups. Our results would give important information in studying the cosmological development of our universe.

Hydrodynamic turbulence driven by crust-core differential rotation imposes a fundamental noise floor on gravitational wave observations of neutron stars. The gravitational wave emission peaks at the Kolmogorov decoherence frequency which, for reasonable values of the crust-core shear, $\Delta \Omega$, occurs near the most sensitive part of the frequency band for ground-based, long-baseline interferometers. We calculate the energy density spectrum of the stochastic gravitational wave background from a cosmological population of turbulent neutron stars generalizing previous calculations for individual sources. The spectrum resembles a piecewise power law, ${\Omega }_{\mathrm{gw}}(\nu )={\Omega }_{\alpha }{\nu }^{\alpha }$, with $\alpha =-1$ and 7 above and below the decoherence frequency respectively, and its normalization scales as ${\Omega }_{\alpha }\propto (\Delta \Omega {)}^7$. Nondetection of a stochastic signal by Initial LIGO implies an upper limit on $\Delta \Omega$ and hence by implication on the internal relaxation time scale for the crust and core to come into corotation, ${\tau }_d=\Delta \Omega /\dot{\Omega }$, where $\dot{\Omega }$ is the observed electromagnetic spin-down rate, with ${\tau }_d\lesssim {10}^7\mathrm{yr}$ for accreting millisecond pulsars and ${\tau }_d\lesssim {10}^5\mathrm{yr}$ for radio-loud pulsars. Target limits on ${\tau }_d$ are also estimated for future detectors, namely Advanced LIGO and the Einstein Telescope, and are found to be astrophysically interesting.

We study the azimuthal asymmetries for quark pair production in proton-nucleus collisions using a hybrid approach in which the nucleus is treated in the color glass condensate framework, while the Lipatov approximation is applied on the proton side. Our treatment goes beyond the large-$N_c$ limit. We particularly focus on the so-called correlation limit where the imbalance of the transverse momentum of the quark pair is much smaller than the outgoing individual quark transverse momenta. In this kinematic region, a matching between the hybrid approach and a factorization in terms of transverse momentum-dependent parton distributions has been found. It is shown which of the various unpolarized and linearly polarized gluon transverse momentum-dependent parton distributiondistributions contribute to $\cos 2\varphi$ and $\cos 4\varphi$ modulations of quark pair production.