In this paper, with the Parikh-Wilczek tunnelling framework the positions of the event horizon of the Vaidya black hole and the Vaidya-Bonner black hole are calculated, respectively. We find that the event horizon and the apparent horizon of these two black holes correspond, respectively, to the two turning points of the Hawking radiation tunnelling barrier. That is, the quantum ergosphere coincides with the tunnelling barrier. Our calculation also implies that the Hawking radiation comes from the apparent horizon.

We identify reactions which destroy ${}^7\mathrm{Be}$ and ${}^7\mathrm{Li}$ during big bang nucleosynthesis (BBN) in the scenario of BBN catalyzed by a long-lived sub-strongly-interacting massive particle (sub-SIMP or $X$ particle). The destruction associated with nonradiative $X$ captures of the nuclei can be realized only if the interaction strength between an $X$ particle and a nucleon is properly weaker than that between two nucleons to a degree depending on the mass of $X$. Binding energies of nuclei to an $X$ particle are estimated taking the mass and the interaction strength to nuclei of the $X$ as input parameters. Nuclear reaction rates associated with the $X$ are estimated naively and adopted in calculating evolutions of nuclear abundances. We suggest that the ${}^7\mathrm{Li}$ problem, which might be associated with as-yet-unrecognized particle processes operating during BBN, can be solved if the $X$ particle interacts with nuclei strongly enough to drive ${}^7\mathrm{Be}$ destruction but not strongly enough to form a bound state with ${}^4\mathrm{He}$ of relative angular momentum $L=1$. Justifications of this scenario by rigorous calculations of reaction rates using quantum mechanical many-body models are highly desirable since this result involves many significant uncertainties.

We compute the amplitudes for the insertion of various operators in a quark 2-point function at one loop in the $\mathrm{R}{\mathrm{I}}^{\prime }$ symmetric momentum scheme, $\mathrm{R}{\mathrm{I}}^{\prime }$/SMOM. Specifically we focus on the moments $n=2$ and 3 of the flavor nonsinglet twist-2 operators used in deep inelastic scattering as these are required for lattice computations.

A measurement of the cross section for the inclusive production of isolated prompt photons in $pp$ collisions at a center-of-mass energy $\sqrt{s}=7\mathrm{TeV}$ is presented. The measurement covers the pseudorapidity ranges $|{\eta }^{\gamma }|<1.37$ and $1.52\le |{\eta }^{\gamma }|<1.81$ in the transverse energy range $15\le E_{\mathrm{T}}^{\gamma }<100\mathrm{GeV}$. The results are based on an integrated luminosity of $880{\mathrm{nb}}^{-1}$, collected with the ATLAS detector at the Large Hadron Collider. Photon candidates are identified by combining information from the calorimeters and from the inner tracker. Residual background in the selected sample is estimated from data based on the observed distribution of the transverse isolation energy in a narrow cone around the photon candidate. The results are compared to predictions from next-to-leading-order perturbative QCD calculations.

A magnetic-monopole solution of a non-Abelian gauge theory as proposed by ’t Hooft and Polyakov is studied in the Vaidya space-time. We find that the solutions of Einstein equations generates a geometry of the Bonnor-Vaidya space-time corresponding to magnetically charged null fluid with Higgs field contributing a cosmological term. In the absence of the scalar fields the corresponding Wu-Yang solution of the gauge theory still generates the Bonnor-Vaidya geometry, but with no cosmological term.

Exact analytical solutions are presented for the time evolution of the density of pairs produced in the QED vacuum by a time-independent, uniform electric field. The mathematical tool used here to describe the pair production is the Dirac-Heisenberg-Wigner function introduced before [Phys. Rev. D 44, 1825 (1991)]. The initial value problem for this function is solved by decomposing the solution into a product of spinors. The equations for spinors are much simpler and are solved analytically. These calculations are nonperturbative since pair production is due to quantum-mechanical tunneling and the explicit solutions clearly exhibit their nonanalytic behavior.

We investigate the occurrence of various exotic spacelike singularities in the past and the future evolution of $k=\pm 1$ Friedmann-Robertson-Walker model and loop quantum cosmology using a sufficiently general phenomenological model for the equation of state. We highlight the nontrivial role played by the intrinsic curvature for these singularities and the new physics which emerges at the Planck scale. We show that quantum gravity effects generically resolve all strong curvature singularities including big rip and big freeze singularities. The weak singularities, which include sudden and big brake singularities, are ignored by quantum gravity when spatial curvature is negative, as was previously found for the spatially flat model. Interestingly, for the spatially closed model there exist cases where weak singularities may be resolved when they occur in the past evolution. The spatially closed model exhibits another novel feature. For a particular class of equation of state, this model also exhibits an additional physical branch in loop quantum cosmology, a baby universe separated from the parent branch. Our analysis generalizes previous results obtained on the resolution of strong curvature singularities in flat models to isotropic spacetimes with nonzero spatial curvature.

We present a numerical solution for a topologically flat two-dimensional thick brane on a higher dimensional, spherically symmetric black hole background. The present solution is the last, missing part of the complete set of solutions for the thickness corrected brane-black hole problem in an arbitrary number of dimensions. We show that the two-dimensional case is special compared to all the higher dimensional solutions in the topologically Minkowskian family as being nonanalytic at the axis of the system. We provide the numerical solution in the near horizon region and make a comparison with the infinitely thin case.

In this paper we consider how non-Gaussianity of the primordial density perturbation and the amplitude of gravitational waves from inflation can be used to determine parameters of the curvaton scenario for the origin of structure. We show that in the simplest quadratic model, where the curvaton evolves as a free scalar field, measurement of the bispectrum relative to the power spectrum, $f_{\mathrm{NL}}$, and the tensor-to-scalar ratio can determine both the expectation value of the curvaton field during inflation and its dimensionless decay rate relative to the curvaton mass. We show how these predictions are altered by the introduction of self-interactions, in models where higher-order corrections are determined by a characteristic mass scale and discuss how additional information about primordial non-Gaussianity and scale dependence may constrain curvaton interactions.

We identify a new inflationary regime for which more than 60 e-folds are generated classically during the waterfall phase occurring after the usual hybrid inflation. By performing a Bayesian Monte-Carlo-Markov-Chain analysis, this scenario is shown to take place in a large part of the parameter space of the model. When this occurs, the observable perturbation modes leave the Hubble radius during waterfall inflation. The power spectrum of adiabatic perturbations is red, possibly in agreement with CMB constraints. Particular attention has been given to study only the regions for which quantum backreactions do not affect the classical dynamics. Implications concerning the preheating and the absence of topological defects in our Universe are discussed.

We study the parameter space of $D$-dimensional cosmological Einstein gravity together with quadratic curvature terms. In $D>4$ there are in general two distinct (anti)-de Sitter vacua. We show that, for an appropriate choice of the parameters, there exists a critical point for one of the vacua, with only massless tensor, but neither massive tensor nor scalar, gravitons. At criticality, the linearized excitations have formally vanishing energy (as do black hole solutions). A further restriction of the parameters gives a one-parameter cosmological Einstein plus ${\mathrm{\text{Weyl}}}^2$ model with a unique vacuum, whose $\Lambda$ is determined.

We consider a vectorial, asymptotically free gauge theory and analyze the effect of higher-loop corrections to the beta function on the evolution of the theory from the ultraviolet to the infrared. We study the case in which the theory contains $N_f$ copies of a fermion transforming according to the fundamental representation and several higher-dimensional representations of the gauge group. We also calculate higher-loop values of the anomalous dimension of the mass, ${\gamma }_m$ of $\overline{\psi }\psi$ at the infrared zero of the beta function. We find that for a given theory, the values of ${\gamma }_m$ calculated to three- and four-loop order, and evaluated at the infrared zero computed to the same order, tend to be somewhat smaller than the value calculated to two-loop order. The results are compared with recent lattice simulations.

By introducing a set of new triplet leptons (with nonzero hypercharge) that can Yukawa couple to their standard model counterparts, new sources of tree-level flavor changing currents are induced via mixing. In this work, we study some of the consequences of such new contributions on processes such as the leptonic decays of gauge bosons, $\ell \to 3{\ell }^{\prime }$ and $\ell \to {\ell }^{\prime }\gamma$, which violate lepton flavor, and $\mu -e$ conversion in atomic nuclei. Constraints are then placed on the parameters associated with the exotic triplets by invoking the current low-energy experimental data. Moreover, the new physics contribution to the lepton anomalous magnetic moments is calculated.

I have measured the precession change of the oscillation plane with an automated Foucault pendulum and found no evidence (within the measurement error) of the Allais effect. The precession speed was registered and, due the variations involved, if the precession speed would changed 0.3 degree per hour (increasing or decreasing the angle of the normal precession speed) during the all eclipse, it would be notice in this measurement.

In this paper we discuss the QCD contribution to the Abelian Debye and magnetic screening masses in a deconfined QCD plasma at finite temperature in the presence of an external magnetic field B. We use a holographic AdS/QCD setup in an AdS Schwarzschild black hole background and show that the electric screening mass has a form similar to the one-loop result in QED. Moreover, we calculate the corrections due to the magnetic field to all orders of B and demonstrate that in the case when the magnetic field is large the Debye mass grows linearly with B, while the magnetic screening mass vanishes. The whole effect of the magnetic field turns out to stem from the Chern-Simons action. We also discuss the zero temperature case in the chiral perturbation theory.

Functional conjugation methods are used to analyze the global structure of various renormalization group trajectories and to gain insight into the interplay between continuous and discrete rescaling. With minimal assumptions, the methods produce continuous flows from step-scaling $\sigma$ functions and lead to exact functional relations for the local flow $\beta$ functions, whose solutions may have novel, exotic features, including multiple branches. As a result, fixed points of $\sigma$ are sometimes not true fixed points under continuous changes in scale and zeroes of $\beta$ do not necessarily signal fixed points of the flow but instead may only indicate turning points of the trajectories.

We consider the scalar, vector and spinor field perturbations in the background of self-dual warped ${\mathrm{AdS}}_3$ black hole of topological massive gravity. The corresponding exact expressions for quasinormal modes are obtained by analytically solving the perturbation equations and imposing the vanishing Dirichlet boundary condition at asymptotic infinity. It is expected that the quasinormal modes agree with the poles of retarded Green’s functions of the CFT dual to self-dual warped ${\mathrm{AdS}}_3$ black hole. Our results provide a quantitative test of the warped AdS/CFT correspondence.

In this paper the zero modes of the de Donder gauge Faddeev-Popov operator for three-dimensional gravity with negative cosmological constant are analyzed. It is found that the ${\mathrm{AdS}}_3$ vacuum produces (infinitely many) normalizable smooth zero modes of the Faddeev-Popov operator. On the other hand, it is found that the Bañados-Teitelboim-Zanelli black hole (including the zero mass black hole) does not generate zero modes. This differs from the usual Gribov problem in QCD where, close to the maximally symmetric vacuum, the Faddeev-Popov determinant is positive definite while “far enough” from the vacuum it can vanish. This suggests that the zero mass Bañados-Teitelboim-Zanelli black hole could be a suitable ground state of three-dimensional gravity with negative cosmological constant. Because of the kinematic origin of this result, it also applies for other covariant gravity theories in three dimensions with ${\mathrm{AdS}}_3$ as maximally symmetric solution, such as new massive gravity and topologically massive gravity. The relevance of these results for supersymmetry breaking is pointed out.

We investigate the stationary end state obtained by evolving a collapsing spherical star with the gauges routinely adopted to study puncture black holes. We compare the end state of the collapse with the trumpet solution found in the evolution of a single wormhole slice and show that the two solutions closely agree. We demonstrate that the agreement is caused by the use of the Gamma-driver shift condition, which allows the matter to fall inwards into a region of spacetime that is not resolved by the numerical grid, and which simultaneously finds the stationary coordinates of the trumpet outside the matter.