We examine meson correlation functions over a large range of lattice spacing and quark mass in simulations with the standard staggered action. We find that the distribution of meson correlation functions is non-Gaussian, with long tails. We modify the statistical analysis to take care of the non-Gaussianity. Current day improvements in the statistical quality of data on hadron correlations further allow us to simplify certain aspects of the analysis of masses. We examine these changes through the analysis of pions and apply them to the vector meson. We also remark on the relation between the vector mass and flow scales.

We employ leading-order covariant chiral perturbation theory to compute the nucleon-pion-state contribution to the 3-point correlation functions one typically measures in lattice QCD to extract the isovector nucleon charges $g_A$, $g_T$ and $g_S$. We estimate the impact of the nucleon-pion-state contribution on both the plateau and the summation method for lattice simulations with physical pion masses. The nucleon-pion-state contribution results in an overestimation of all charges with both methods. The overestimation is roughly equal for the axial and the tensor charge, and about 50% larger for the scalar charge.

We explore the reach of a 100 TeV proton collider to discover Kaluza-Klein gluons in a warped extra dimension. These particles are templates for color adjoint vectors that couple dominantly to the top quark. We examine their production rate at NLO in the six-flavor m-ACOT scheme for a variety of reference models defining their coupling to quarks, largely inspired by the Randall-Sundrum model of a warped extra dimension. In agreement with previous calculations aimed at lower-energy machines, we find that the NLO corrections are typically negative, resulting in a $K$ factor of around 0.7 (depending on the model) and a residual scale dependence on the order of $\pm 20\%$, greater than the variation from the scale exhibited by the naïve LO estimate.

There are five maximally supersymmetric backgrounds in four-dimensional off-shell $\mathcal{N}=1$ supergravity, two of which are well known: Minkowski superspace ${\mathbb{M}}^{4|4}$ and anti–de Sitter superspace ${\mathrm{AdS}}^{4|4}$. The three remaining supermanifolds support spacetimes of different topology, which are $\mathbb{R}\times S^3$, ${\mathrm{AdS}}_3\times \mathbb{R}$, and a supersymmetric plane wave isometric to the Nappi-Witten group. As is well known, the Minkowski and anti–de Sitter superspaces are solutions of the Poincaré and anti–de Sitter supergravity theories, respectively. Here we demonstrate that the other three superspaces are solutions of pure $R^2$ supergravity. We also present a new (probably the simplest) derivation of the maximally supersymmetric backgrounds of off-shell $\mathcal{N}=1$ supergravity.

We obtain a large class of new four-dimensional Argyres-Douglas theories by classifying irregular punctures for the six-dimensional (2, 0) superconformal theory of ADE type on a sphere. Along the way, we identify the connection between the Hitchin system and threefold singularity descriptions of the same Argyres-Douglas theory. Other constructions such as taking degeneration limits of the irregular puncture, adding an extra regular puncture, and introducing outer-automorphism twists are also discussed. Later we investigate various features of these theories including their Coulomb branch spectrum and central charges.

In this paper we study the zero energy solutions of the Dirac equation in the background of a $Z_2$ vortex of a non-Abelian gauge model with three charged scalar fields. We determine the number of the fermionic zero modes giving their explicit form for two specific Ansätze.

An exact correspondence between a black hole and an accelerating mirror is demonstrated. It is shown that for a massless minimally coupled scalar field, the same Bogolubov coefficients connecting the “in” and “out” states occur for a ($1+1$)-dimensional flat spacetime with a particular perfectly reflecting accelerating boundary trajectory and a ($1+1$)-dimensional curved spacetime in which a null shell collapses to form a black hole. Generalization of the latter to the ($3+1$)-dimensional case is discussed. The spectral dynamics is computed in both ($1+1$)-dimensional spacetimes along with the energy flux in the spacetime with a mirror. It is shown that the approach to equilibrium is monotonic, asymmetric in terms of the rate, and there is a specific time which characterizes the system when it is the most out of equilibrium.

An explicit Robinson-Trautman solution with a minimally coupled free scalar field was derived and analyzed recently. It was shown that this solution possesses a curvature singularity which is initially naked but later enveloped by a horizon. However, this study concentrated on the general branch of the solution where all free constants are nonzero. Interesting special cases arise when some of the parameters are set to zero. In most of these cases, the scalar field is still present. One of the cases is a static solution which represents a parametric limit of the Janis-Newman-Winicour scalar field spacetime. Additionally, we provide a calculation of the Bondi mass which clarifies the interpretation of the general solution. Finally, by a complex rotation of a parameter describing the strength of the scalar field, we obtain a dynamical wormhole solution.

In this paper, we study a physical system that is composed of a massive charged scalar field linearly coupled to a charged rotating Kerr-Newman black hole. Given the parameters of the black hole and a specific set of "quantum" numbers, the parameter space of the scalar field, which is a plane spanned by its mass and charge, is divided into five partitions by three simple constraint lines and the existence line of scalar clouds. The physical properties of the system in these partitions are presented. It is found that superradiant instability may be possibly caused only in two of the partitions. In particular, it is shown that both the mass and charge of the scalar clouds are bounded in a limited region. Our results may be used to rapidly judge the possible occurrence of superradiant instability and the existence of scalar clouds around a given black hole.

We study the self-similar motion of a string in a self-similar spacetime by introducing the concept of a self-similar string, which is defined as the world sheet to which a homothetic vector field is tangent. It is shown that in Nambu-Goto theory, the equations of motion for a self-similar string reduce to those for a particle. Moreover, under certain conditions such as the hypersurface orthogonality of the homothetic vector field, the equations of motion for a self-similar string simplify to the geodesic equations on a (pseudo)Riemannian space. As a concrete example, we investigate a self-similar Nambu-Goto string in a spatially flat Friedmann-Lemaître-Robertson-Walker expanding universe with self-similarity and obtain solutions of open and closed strings, which have various nontrivial configurations depending on the rate of the cosmic expansion. For instance, we obtain a circular solution that evolves linearly in the cosmic time while keeping its configuration by the balance between the effects of the cosmic expansion and string tension. We also show the instability for linear radial perturbation of the circular solutions.

We study time-dependent Hawking-like radiation as seen by an infalling observer during gravitational collapse of a thin shell. We calculate the occupation number of particles of which the frequencies are measured in the proper time of an infalling observer in Eddington-Finkelstein coordinates. We solve the equations for the whole process from the beginning of the collapse till the moment when the collapsing shell reaches zero radius. The radiation distribution is not thermal in the whole frequency regime, but it is approximately thermal for the wavelengths of the order of the Schwarzschild radius of the collapsing shell. After the Schwarzschild radius is crossed, the temperature increases without limits as the singularity is approached. We also calculate the density matrix associated with this radiation. It turns out that the off-diagonal correlation terms to the diagonal Hawking leading-order terms are very important. While the trace of the diagonal (Hawking) density matrix squared decreases during the evolution, the trace of the total density matrix squared remains unity at all times and all frequencies.

The perturbative approach to structure formation has recently received a lot of attention in the literature. In such setups the final predictions for observables like the power spectrum is often derived under additional approximations such as a simplified time dependence. Here we provide all-order perturbative integral solutions for density and velocity fields in generalized cosmologies, with a direct application to clustering quintessence. We go beyond the standard results based on extending the EdS-like approximations. As an illustrative example, we apply our findings to the calculation of the one-loop power spectrum of density and momentum fields. We find corrections close to 1% in the mildly nonlinear regime of $\mathrm{\Lambda }\mathrm{CDM}$ cosmologies for the density power spectrum, while in the case of the density-momentum power spectrum effects can reach up to 1.5% for $k\sim 0.2h/\mathrm{Mpc}$.

Dark matter (DM) may have a relic density that is in part determined by a particle/antiparticle asymmetry, much like baryons. If this is the case, it can accumulate in stars like the Sun to sizable number densities and annihilate to Standard Model particles including neutrinos. We show that the combination of neutrino telescope and direct detection data can be used in conjunction to determine or constrain the DM asymmetry from data. Depending on the DM mass, the current neutrino data from Super-Kamiokande and IceCube give powerful constraints on asymmetric DM unless its fractional asymmetry is $\lesssim {10}^{-2}$. Future neutrino telescopes and detectors like Hyper-K and KM3NeT can search for the resulting signal of high-energy neutrinos from the center of the Sun. The observation of such a flux yields information on both the DM-nucleus cross section and also on the relative abundances of DM and anti-DM.

We test the viability of the Higgs-dilaton model (HDM) compared to the evolving dark energy ($w_0{w}_a\mathrm{CDM}$) model, in which the cosmological constant model $\mathrm{\Lambda }\mathrm{CDM}$ is also nested, by using the latest cosmological data that include the cosmic microwave background temperature, polarization and lensing data from the Planck satellite (2015 data release), the BICEP and Keck Array experiments, the Type Ia supernovae from the JLA catalog, the baryon acoustic oscillations from CMASS, LOWZ and 6dF, the weak lensing data from the CFHTLenS survey, and the matter power spectrum measurements from the SDSS (data release 7). We find that the values of all cosmological parameters allowed by the Higgs-dilaton model inflation are well within the Planck satellite (2015 data release) constraints. In particular, we have that $w_0=-1.0001_{-0.0074}^{+0.0072}$, $w_a=0.00_{-0.16}^{+0.15}$, $n_s=0.9693_{-0.0082}^{+0.0083}$, ${\alpha }_s=-0.001_{-0.014}^{+0.013}$ and $r_{0.05}=0.0025_{-0.0016}^{+0.0017}$ (95.5% C.L.). We also place new stringent constraints on the couplings of the Higgs-dilaton model and we find that ${\xi }_{\chi }<0.00328$ and ${\xi }_h/\sqrt{\lambda }=59200_{-20000}^{+30000}$ (95.5% C.L.). Furthermore, we report that the HDM is on slightly better footing than the $w_0{w}_a\mathrm{CDM}$ model, as they both have practically the same chi-square, i.e. $\mathrm{\Delta }{\chi }^2={\chi }_{w_0{w}_a\mathrm{CDM}}^2-{\chi }_{\mathrm{HDM}}^2=0.18$, with the HDM model having two fewer parameters. Finally, Bayesian evidence favors equally the two models, with the HDM being preferred by the AIC and DIC information criteria.

The next generation of experiments in particle physics will for the first time systematically test flavor physics models based on flavon fields. Starting from the current quark-flavor constraints on such models we show how the new generation of lepton flavor experiments will dominate indirect searches in the coming decades. A future 100 TeV hadron collider will then be the first experiment to probe flavons as propagating degrees of freedom. Our estimate of the collider reach relies on a proper treatment of backgrounds and detector effects. Complementary searches for indirect effects in lepton flavor experiments and propagating degrees of freedom at colliders are very limited at the LHC, but will be a new feature at a 100 TeV hadron collider.

We consider the Higgs-radion mixing in the context of warped space extradimensional models with custodial symmetry and investigate the prospects of detecting the mixed radion. Custodial symmetries allow the Kaluza-Klein excitations to be lighter and protect $Zb\overline{b}$ to be in agreement with experimental constraints. We perform a complementary study of discovery reaches of the Higgs-radion mixed state at the 13 and 14 TeV LHC and at the 500 and 1000 GeV International Linear Collider (ILC). We carry out a comprehensive analysis of the most significant production and decay modes of the mixed radion in the 80 GeV–1 TeV mass range and indicate the parameter space that can be probed at the LHC and the ILC. There exists a region of the parameter space which can be probed, at the LHC, through the diphoton channel even for a relatively low luminosity of $50{\mathrm{fb}}^{-1}$. The reach of the four-lepton final state in probing the parameter space is also studied in the context of 14 TeV LHC, for a luminosity of $1000{\mathrm{fb}}^{-1}$. At the ILC, with an integrated luminosity of $500{\mathrm{fb}}^{-1}$, we analyze the $Z$-radion associated production and the $WW$ fusion production, followed by the radion decay into $b\overline{b}$ and $W^{+}{W}^{-}$. The $WW$ fusion production is favored over the $Z$-radion associated channel in probing regions of the parameter space beyond the LHC reach. The complementary study at the LHC and the ILC is useful both for the discovery of the radion and the understanding of its mixing sector.

We explore the implications of monojet searches at hadron colliders in the minimal supersymmetric extension of the Standard Model (MSSM). To quantify the impact of monojet searches, we consider simplified MSSM scenarios with neutralino dark matter. The monojet results of the LHC Run 1 are reinterpreted in the context of several MSSM simplified scenarios, and the complementarity with direct supersymmetry search results is highlighted. We also investigate the reach of monojet searches for the Run 2, as well as for future higher energy hadron colliders.

It has been proposed that the observed diphoton excess at 750 GeV could be explained within the constrained minimal supersymmetric standard model via resonantly produced stop bound states. We reanalyze this scenario critically and extend previous work to include the constraints from the stability of the electroweak vacuum and from the decays of the stoponium into a pair of Higgs bosons. It is shown that the interesting regions of parameter space with a light stop and Higgs of the desired mass are ruled out by these constraints. This conclusion is not affected by the presence of the bound states because the binding energy is usually very small in the regions of parameter space which can explain the Higgs mass. Thus, this also leads to strong constraints on the diphoton production cross section which is in general too small.

We study a radiative neutrino model with a SU(2) septet scalar with hypercharge $Y=2$ where active neutrino mass is induced at a one-loop level. Calculating a one-loop diagram, mass matrices for an active neutrino are derived. We also analyze lepton flavor violations, the anomalous magnetic moment of a muon, and the flavor-violating Higgs decay $h\to \mu \tau$. Then, sizable muon $g-2$ and $\sim 1\%$ of $\mathrm{BR}(h\to \mu \tau )$ could be obtained in our setup. Furthermore, the collider signature of the septet is discussed, and we focus on the quadratically charged scalar at the LHC 14 TeV. We find that it could be discovered up to 1.5 TeV mass by searching multicharged lepton signal events.