We discuss the behavior of the Dirac fermions in a general spherically symmetric black hole background with a nontrivial topology of the event horizon. Both massive and massless cases are taken into account. We will conduct an analytical study of intermediate and late-time behavior of massive Dirac hair in the background of a black hole with a global monopole and dilaton black hole pierced by a cosmic string. In the case of a global monopole swallowed by a static black hole, the intermediate late-time behavior depends on the mass of the Dirac field, the multiple number of the wave mode, and the global monopole parameter. The late-time behavior is quite independent of these factors and has a decay rate proportional to $t^{-5/6}$. As far as the black hole pierced by a cosmic string is concerned, the intermediate late-time behavior depends only on the hair mass and the multipole number of the wave mode, while the late-time behavior dependence is the same as in the previous case. The main modification stems from the topology of the $S^2$ sphere pierced by a cosmic string. This factor modifies the eigenvalues of the Dirac operator acting on the transverse manifold.

In Newtonian theory, gravity inside a constant density static sphere is independent of spacetime dimension. Interestingly this general result is also carried over to Einsteinian as well as higher order Einstein-Gauss-Bonnet (Lovelock) gravity notwithstanding their nonlinearity. We prove that the necessary and sufficient condition for universality of the Schwarzschild interior solution describing a uniform density sphere for all $n\ge 4$ is that its density is constant.

A constraint on the viable $f(R)$ model is investigated by confronting theoretical predictions with the multipole power spectrum of the luminous red galaxy sample of the Sloan Digital Sky Survey, data release 7. We obtain a constraint on the Compton wavelength parameter of the $f(R)$ model on the scales of cosmological large-scale structure. A prospect of constraining the Compton wavelength parameter with a future redshift survey is also investigated. The usefulness of the redshift-space distortion for testing the gravity theory on cosmological scales is demonstrated.

In a universe with a detectable nontrivial spatial topology, the last scattering surface contains pairs of matching circles with the same distribution of temperature fluctuations—the so-called circles-in-the-sky. Searches for nearly antipodal circles-in-the-sky in maps of cosmic microwave background radiation have so far been unsuccessful. This negative outcome, along with recent theoretical results concerning the detectability of nearly flat compact topologies, is sufficient to exclude a detectable nontrivial topology for most observers in very nearly flat positively and negatively curved universes, whose total matter-energy density satisfies $0<|{\Omega }_{\mathrm{tot}}-1|\lesssim {10}^{-5}$. Here, we investigate the consequences of these searches for observable nontrivial topologies if the Universe turns out to be exactly flat (${\Omega }_{\mathrm{tot}}=1$). We demonstrate that in this case, the conclusions deduced from such searches can be radically different. We show that, although there is no characteristic topological scale in the flat manifolds, for all multiply-connected orientable flat manifolds, it is possible to directly study the action of the holonomies in order to obtain a general upper bound on the angle that characterizes the deviation from antipodicity of pairs of matching circles associated with the shortest closed geodesic. This bound is valid for all observers and all possible values of the compactification length parameters. We also show that in a flat universe, there are observers for whom the circles-in-the-sky searches already undertaken are insufficient to exclude the possibility of a detectable nontrivial spatial topology. It is remarkable how such small variations in the spatial curvature of the Universe, which are effectively indistinguishable geometrically, can have such a drastic effect on the detectability of cosmic topology. Another important outcome of our results is that they offer a framework with which to make statistical inferences from future circles-in-the-sky searches on whether the Universe is exactly flat.

Following a model based on the SU(8) symmetry that treats heavy pseudoscalars and heavy vector mesons on an equal footing, as required by heavy quark symmetry, we study the interaction of baryons and mesons in coupled channels within an unitary approach that generates dynamically poles in the scattering $T$-matrix. We concentrate in the exotic channels with negative charm quantum number for which there is the experimental claim of one state.

Screenings of the quark-gluon plasma in electric and magnetic sectors are studied on the basis of generalized Polyakov-line correlation functions in lattice QCD simulations with two flavors of improved Wilson quarks. Using the Euclidean-time reflection ($\mathcal{R}$) and the charge conjugation ($\mathcal{C}$), electric and magnetic screening masses are extracted in a gauge-invariant manner. Long distance behavior of the standard Polyakov-line correlation in the quark-gluon plasma is found to be dictated by the magnetic screening. Also, the ratio of the two screening masses agrees with that obtained from the dimensionally-reduced effective field theory and the $\mathcal{N}=4$ supersymmetric Yang-Mills theory.

This paper is devoted to the study of the open string description of Wilson loops and quarks in nonrelativistic quantum field theory that are expected to be dual of gravity in Schrödinger space-time.

On an interval compactification in supersymmetric theory, boundary conditions for bulk fields must be treated carefully. If they are taken arbitrarily following the requirement that a theory is supersymmetric, the conditions could give redundant constraints on the theory. We construct a supersymmetric action integral on an interval by introducing brane interactions with which total-derivative terms under the supersymmetry transformation become zero due to a cancellation. The variational principle leads equations of motion and also boundary conditions for bulk fields, which determine boundary values of bulk fields. By estimating mass spectrum, spontaneous supersymmetry breaking in this simple setup can be realized in a new framework. This supersymmetry breaking does not induce a massless $R$ axion, which is favorable for phenomenology. It is worth noting that fermions in hyper-multiplet, gauge bosons, and the fifth-dimensional component of gauge bosons can have zero-modes (while the other components are all massive as Kaluza-Klein modes), which fits the gauge-Higgs unification scenarios.

We consider an effective theory with an $SU(2)\times U(1)\times A_4\times Z_2\times Z_4$ symmetry and investigate the possibility of a linking TeV-leptogenesis with a reactor angle $|U_{e3}|$ through $A_4$ symmetry breaking which is at a scale higher than electroweak scale under the framework of radiative seesaw. It has been shown that tribimaximal (TBM) mixing can be obtained by forging vacuum expectation value alignment of the $A_4$. Especially, one $A_4$ triplet scalar field with cutoff scale $\Lambda$ is added in neutrino Yukawa sector, which is responsible for the deviation of the exact TBM, to explain leptogenesis as well as a nonzero $|U_{e3}|$. Above the scale of $\Lambda$ the leptonic Yukawa sectors will lead to the exact TBM. We analyze possible spectrums of light neutrinos and their flavor mixing angles corresponding to heavy Majorana neutrino mass ordering, and show that nonresonance leptogenesis at TeV scale constrained by low energy data is achievable, both analytically as well as numerically. We show that only normal hierarchical spectrum of light neutrino would be strongly favored by the current Wilkinson Microwave Anisotropy Probe data, and also show that a relatively large $|U_{e3}|$ corresponds to the value of baryon asymmetry $6.2\times {10}^{-10}$.

We introduce the isothermal cavity, static holographic screen, and accelerating surface as holographic screen to study the entropic force in the presence of the Schwarzschild black hole. These may merge to provide a consistent holographic screen to define the entropic force on the stretched horizon near the event horizon. Considering the similarity between the stretched horizon of black hole and the entanglement system, we may define the entropic force in the entanglement system without referring to the source mass.

We present a noncanonically symplectic integration scheme tailored to numerically computing the post-Newtonian motion of a spinning black-hole binary. Using a splitting approach we combine the flows of orbital and spin contributions. In the context of the splitting, it is possible to integrate the individual terms of the spin-orbit and spin-spin Hamiltonians analytically, exploiting the special structure of the underlying equations of motion. The outcome is a symplectic, time-reversible integrator, which can be raised to arbitrary order by composition. A fourth-order version is shown to give excellent behavior concerning error growth and conservation of energy and angular momentum in long-term simulations. Favorable properties of the integrator are retained in the presence of weak dissipative forces due to radiation damping in the full post-Newtonian equations.

We study the bulk corresponding to tidal charged brane-world black holes. We employ a propagating algorithm which makes use of the three-dimensional multipole expansion and analytically yields the metric elements as functions of the five-dimensional coordinates and of the Adler-Deser-Misner mass, tidal charge, and brane tension. Since the projected brane equations cannot determine how the charge depends on the mass, our main purpose is to select the combinations of these parameters for which black holes of microscopic size possess a regular bulk. Our results could, in particular, be relevant for a better understanding of TeV-scale black holes.

We describe a possible realization of the spontaneous baryogenesis mechanism in the context of extra-dimensional string cosmology and specifically in the string gas scenario.

Beam asymmetries result in statistically anisotropic cosmic microwave background (CMB) maps. Typically, they are studied for their effects on the CMB power spectrum, however they more closely mimic anisotropic effects such as gravitational lensing and primordial power asymmetry. We discuss tools for studying the effects of beam asymmetry on general quadratic estimators of anisotropy, analytically for full-sky observations as well as in the analysis of realistic data. We demonstrate this methodology in application to a recently detected $9\sigma$ quadrupolar modulation effect in the WMAP data, showing that beams provide a complete and sufficient explanation for the anomaly.

In this article, we work out the properties of the $B$, $D$, and $D^{*}$ mesons as well as the $B\to D(D^{*})e{\nu }_e$ decay properties at finite temperature QCD. The behavior of the masses, decay constants and widths of the $B$, $D$, and $D^{*}$ mesons in terms of the temperature is studied. The temperature dependency of the form factors responsible for such decays are also obtained. These temperature-dependent form factors are used to investigate the variation of the branching ratios with respect to the temperature. It is shown that the branching ratios do not change up to $T/T_c=0.3$, however they start to diminish with increasing the temperature after this region and vanish at the critical or deconfinement temperature.

Chirally enhanced supersymmetric QCD corrections to flavor-changing neutral current processes are investigated in the framework of the minimal supersymmetric standard model with generic sources of flavor violation. These corrections arise from flavor-changing self-energy diagrams and can be absorbed into a finite renormalization of the squark-quark-gluino vertex. In this way enhanced two-loop and even three-loop diagrams can be efficiently included into a leading-order calculation. Our corrections substantially change the values of the parameters ${\delta }_{23}^{d\mathrm{LL}}$, ${\delta }_{23}^{d\mathrm{LR}}$, ${\delta }_{23}^{d\mathrm{RL}}$, and ${\delta }_{23}^{d\mathrm{RR}}$ extracted from $\mathrm{Br}[B\to X_s\gamma ]$ if $\tan \beta$ is large. We find stronger (weaker) constraints compared to the leading-order result for negative (positive) values of $\mu$. The constraints on ${\delta }_{13}^{d\mathrm{LR},\mathrm{RL}}$ and ${\delta }_{23}^{d\mathrm{LR},\mathrm{RL}}$ from $B_d-{\overline{B}}_d$ and $B_s-{\overline{B}}_s$ mixing change drastically if the third-generation squark masses differ from those of the first two generations. $K-\overline{K}$ mixing is more strongly affected by the chirally enhanced loop diagrams and even subpercent deviations from degenerate down and strange squark masses lead to profoundly stronger constraints on ${\delta }_{12}^{d\mathrm{LR},\mathrm{RL}}$.

We derive the rapidity evolution equation for the gluon four-point function in the dilute regime and at small $x$ from the JIMWLK functional equation. We show that beyond leading order in $N_c$ the mean field (Gaussian) approximation where the four-point function is factorized into a product of two-point functions is violated. We calculate these factorization breaking terms and show that they contribute at leading order in $N_c$ to correlations of two produced gluons as a function of their relative rapidity and azimuthal angle, for generic (rather than back-to-back) angles. Such two-particle correlations have been studied experimentally at the BNL-RHIC collider and could be scrutinized also for $pp$ (and, in the future, also $AA$) collisions at the CERN-LHC accelerator.

Using the radiative return method, experiments at high luminosity electron-positron colliders allow one to explore the kaon and the pion form factors in the timelike region up to fairly high energies. This opens the possibility to study kaon and pion pair production at and around the narrow resonances $J/\psi$ and $\psi (2S)$ and to explore the interference between electromagnetic and hadronic amplitudes. Parametrizations of charged and neutral kaon as well as pion form factors are derived, which lead to an improved description of the data in the region of large invariant masses of the meson pair. These form factors are combined with the hadronic couplings of charged and neutral kaons to $J/\psi$ and $\psi (2S)$ and implemented into the Monte Carlo generator PHOKHARA, which is now, for the first time, able to simulate the production of narrow resonances and their decay into kaon, pion, and muon pairs.

The relationship between the nonperturbative Green’s functions of Yang-Mills theory and the confinement potential is investigated. By rewriting the generating functional of quantum chromodynamics in terms of a heavy quark mass expansion in Coulomb gauge, restricting to leading order in this expansion and considering only the two-point functions of the Yang-Mills sector, the rainbow-ladder approximation to the gap and Bethe-Salpeter equations is shown to be exact in this case and an analytic, nonperturbative solution is presented. It is found that there is a direct connection between the string tension and the temporal gluon propagator. Further, it is shown that for the 4-point quark correlation functions, only confined bound states of color-singlet quark-antiquark (meson) and quark-quark (baryon) pairs exist.