We investigate the impact of nonlinear evolution of the gravitational potentials in the $\Lambda \mathrm{CDM}$ model on the integrated Sachs-Wolfe (ISW) contribution to the cosmic microwave background (CMB) temperature power spectrum, and on the cross-power spectrum of the CMB and a set of biased tracers of the mass. We use an ensemble of $N$-body simulations to directly follow the potentials and compare the results to analytic PT methods. The predictions from the PT match the results to high precision for $k<0.2h{\mathrm{Mpc}}^{-1}$. We compute the nonlinear corrections to the angular power spectrum and find them to be $<10\%$ of linear theory for $l<100$. These corrections are swamped by the cosmic variance. On scales $l>100$ the departures are more significant; however, the CMB signal is more than a factor ${10}^3$ larger at this scale. Nonlinear ISW effects therefore play no role in shaping the CMB power spectrum for $l<1500$. We analyze the CMB-density tracer cross spectrum using simulations and renormalized bias PT, and find good agreement. The usual assumption is that nonlinear evolution enhances the growth of structure and counteracts the linear ISW on small scales, leading to a change in sign of the CMB large-scale structure cross spectrum at small scales. However, PT analysis suggests that this trend reverses at late times when the logarithmic growth rate $f=d\ln D/d\ln a<0.5$ or ${\Omega }_m(z)<0.3$. Numerical results confirm these expectations and we find no sign change in ISW large-scale structure cross power for low redshifts. Corrections due to nonlinearity and scale dependence of the bias are found to be $<10\%$ for $l<100$, and are therefore below the signal to noise of the current and future measurements. Finally, we estimate the cross-correlation coefficient between the CMB and halos and show that it can be made to match that for the dark matter and CMB to within 5% for thin redshift shells, thus mitigating the need to model bias evolution.

Cosmic parallax is the change of angular separation between a pair of sources at cosmological distances induced by an anisotropic expansion. An accurate astrometric experiment like Gaia could observe or put constraints on cosmic parallax. Examples of anisotropic cosmological models are Lemaitre-Tolman-Bondi void models for off-center observers (introduced to explain the observed acceleration without the need for dark energy) and Bianchi metrics. If dark energy has an anisotropic equation of state, as suggested recently, then a substantial anisotropy could arise at $z\lesssim 1$ and escape the stringent constraints from the cosmic microwave background. In this paper we show that such models could be constrained by the Gaia satellite or by an upgraded future mission.

We show that, in the presence of a string gas, simple higher-derivative modifications to the effective action for gravity can lead to bouncing and cyclic cosmological models. The modifications bound the expansion rate and avoid singularities at finite times. In these models the scale factors can have long loitering phases that solve the horizon problem. Adding a potential for the dilaton gives a simple realization of the pre-big bang scenario. Entropy production in the cyclic phase drives an eventual transition to a radiation-dominated Universe. As a test of the Brandenberger-Vafa scenario, we comment on the probability of decompactifying three spatial dimensions in this class of models.

An impressive progress in measurements of the $D^0-{\overline{D}}^0$ mixing parameters has been made in recent years. We explore the implications of these measurements to models of new physics, especially in view of recent upper bounds on the amount of $CP$ violation. We update the constraints on nonrenormalizable four-quark operators. We show that the experiments are close to probing minimally flavor violating models with large $\tan \beta$. The data challenge models with a scale of order TeV where the flavor violation in the down sector is suppressed by alignment and, in particular, certain classes of supersymmetric models and of warped extra dimension models.

We study exclusive $B_s$ decays to final states with $\eta$ and ${\eta }^{\prime }$, induced by the rare $b\to s{\ell }^{+}{\ell }^{-}$ and $b\to s\nu \overline{\nu }$ transitions. Differential decay rates and total branching fractions are predicted in the standard model, adopting the flavor scheme for the description of the $\eta -{\eta }^{\prime }$ mixing. We discuss the theoretical uncertainty related to the hadronic matrix elements. We also consider these decay modes in a new physics scenario with a single universal extra dimension, studying the dependence of branching ratios and decay distributions on the compactification scale $R^{-1}$ of the extra dimension.

The three-site model has been offered as a benchmark for studying the collider phenomenology of Higgsless models. In this paper we analyze how well the three-site model performs as a general exemplar of Higgsless models in describing $W_L{W}_L$ scattering, and which modifications can make it more representative. We employ general sum rules relating the masses and couplings of the Kaluza-Klein modes of the gauge fields in continuum and deconstructed Higgsless models as a way to compare the different theories. We show that the size of the four-point vertex for the (unphysical) Nambu-Goldstone modes and the degree to which the sum rules are saturated by contributions from the lowest-lying Kaluza-Klein resonances both provide good measures of the extent to which a highly deconstructed theory can accurately describe the low-energy physics of a continuum 5D Higgsless model. After comparing the three-site model to flat and warped continuum models, we analyze extensions of the three-site model to a longer open linear moose with an additional $U(1)$ group and to a ring (“breaking electroweak symmetry strongly” or “hidden local symmetry”) model with three sites and three links. Both cases may be readily analyzed in the framework of the general sum rules. We demonstrate that $W_L{W}_L$ scattering in the ring model can very closely approximate scattering in the continuum models, provided that the hidden local symmetry parameter $a$ is chosen to mimic $\rho$-meson dominance of $\pi \pi$ scattering in QCD. The hadron and lepton collider phenomenology of both extended models is briefly discussed, with a focus on the complementary information to be gained from precision measurements of the $Z^{\prime }$ line shape and $ZWW$ coupling at a high-energy lepton collider.

The mechanism of non-Abelian color confinement is studied in SU(2) lattice gauge theory in terms of the Abelian fields and monopoles extracted from non-Abelian link variables without adopting gauge fixing. First, the static quark-antiquark potential and force are computed with the Abelian and monopole Polyakov loop correlators, and the resulting string tensions are found to be identical to the non-Abelian string tension. These potentials also show the scaling behavior with respect to the change of lattice spacing. Second, the profile of the color-electric field between a quark and an antiquark is investigated with the Abelian and monopole Wilson loops. The color-electric field is squeezed into a flux tube due to monopole supercurrent with the same Abelian color direction. The parameters corresponding to the penetration and coherence lengths show the scaling behavior, and the ratio of these lengths, i.e., the Ginzburg-Landau parameter, indicates that the vacuum type is near the border of the type 1 and type 2 (dual) superconductors. These results are summarized in which the Abelian fundamental charge defined in an arbitrary color direction is confined inside a hadronic state by the dual Meissner effect. As the color-neutral state in any Abelian color direction corresponds to the physical color-singlet state, this effect explains non-Abelian color confinement and supports the existence of a gauge-invariant mechanism of color confinement due to the dual Meissner effect caused by Abelian monopoles.

The chiral magnetic effect is the generation of electric current of quarks along an external magnetic field in the background of topologically nontrivial gluon fields. There is recent evidence that this effect is observed by the STAR Collaboration in heavy-ion collisions at the Relativistic Heavy Ion Collider. In our paper we study qualitative signatures of the chiral magnetic effect using quenched lattice simulations. We find indications that the electric current is indeed enhanced in the direction of the magnetic field both in equilibrium configurations of the quantum gluon fields and in a smooth gluon background with nonzero topological charge. In the confinement phase the magnetic field enhances the local fluctuations of both the electric charge and chiral charge densities. In the deconfinement phase the effects of the magnetic field become smaller, possibly due to thermal screening. Using a simple model of a fireball we obtain a good agreement between our data and experimental results of STAR Collaboration.

For lattice models with compact field integration (nonlinear sigma models over compact manifolds and gauge theories with compact groups) and satisfying some discrete symmetry, the change of sign of the bare coupling $g_0^2$ at zero results in a mere discontinuity in the average energy rather than the catastrophic instability occurring in theories with integration over arbitrarily large fields. This indicates that the large order of perturbative series and the nonperturbative contributions should have unexpected features. Using the large-$N$ limit of two-dimensional nonlinear $O(N)$ sigma model, we discuss the complex singularities of the average energy for complex ’t Hooft coupling ${\lambda }^t=g_0^{2}N$. A striking difference with the usual situation is the absence of the cut along the negative real axis. We show that the zeros of the partition function can only be inside a clover shape region of the complex ${\lambda }^t$ plane. We calculate the density of states and use the result to verify numerically the statement about the zeros. We propose dispersive representations of the derivatives of the average energy for an approximate expression of the discontinuity. The discontinuity is purely nonperturbative and contributions at small negative coupling in one dispersive representation are essential to guarantee that the derivatives become exponentially small when ${\lambda }^t\to 0^{+}$. We discuss the implications for gauge theories.

We report on further evidence that the $Y(3940)$ and the recently observed $Y(4140)$ are heavy hadron molecule states with quantum numbers $J^{PC}=0^{++}$. The $Y(3940)$ state is considered to be a superposition of $D^{*+}{D}^{*-}$ and $D^{*0}\overline{D^{*0}}$, while the $Y(4140)$ is a bound state of $D_s^{*+}$ and $D_s^{*-}$ mesons. For the first time we give predictions for the strong $Y(3940)\to J/\psi \omega$, $Y(4140)\to J/\psi \varphi$ and radiative $Y(3940)/Y(4140)\to \gamma \gamma$ decay widths in a phenomenological Lagrangian approach. Results for the strong $J/\psi V$ ($V=\omega$, $\varphi$) decays clearly support the molecular interpretation of the $Y(3940)$ and $Y(4140)$. The alternative assignment of $J^{PC}=2^{++}$ is also tested, giving similar results for the strong decay widths.

We demonstrate the equivalence of the light-front and equal-time formulations of pionic corrections to nucleon properties. As a specific example, we consider the self-energy $\Sigma$ of a nucleon dressed by pion loops, for both pseudovector and pseudoscalar $\pi NN$ couplings. We derive the leading and next-to-leading nonanalytic behavior of $\Sigma$ on the light front, and show explicitly their equivalence in the rest frame and infinite momentum frame in equal-time quantization, as well as in a manifestly covariant formulation.

The process of charged Higgs production in association with a top quark at the LHC has been calculated at the complete next-to-leading-order electroweak level both in a two-Higgs-doublet model and in the minimal supersymmetric standard model, assuming a minimal supergravity breaking scheme. We have numerically explored the size of the one-loop corrections in two typical supersymmetric scenarios, with particular attention to the $\tan \beta$ dependence, and we have found that they remain perturbatively small but possibly sizable, reaching a 20% limit for extreme values of $\tan \beta$, when the complete set of Feynman diagrams is taken into account.

We investigate resonance structures in $CPT$ and Lorentz symmetry-violating neutrino-antineutrino oscillations in a two generation framework. The neutrino-antineutrino oscillations are induced by Lorentz- and $CPT$-violating terms in the Hamiltonian. The resonances are suitably described in terms of charge conjugation eigenstates of the system. The relations among the flavor, charge conjugation and mass eigenbasis of neutrino-antineutrino oscillations are examined along with the interplay between the available $CPT$-violating parameter space and possible resonance structures. Eventually we remark on the consequences of such scenarios for neutrino oscillation experiments, namely, possible solutions for the LSND and MiniBooNE anomalies.

We present the results of a Bayesian analysis of solar and KamLAND neutrino data in the framework of three-neutrino mixing. We adopt two approaches for the prior probability distribution of the oscillation parameters $\Delta m_{21}^2$, ${sin}^2{\vartheta }_{12}$, ${sin}^2{\vartheta }_{13}$: (1) a traditional flat uninformative prior; and (2) an informative prior which describes the limits on ${sin}^2{\vartheta }_{13}$ obtained in atmospheric and long-baseline accelerator and reactor neutrino experiments. In both approaches, we present the allowed regions in the ${sin}^2{\vartheta }_{13}\mathrm{\text{−}}\Delta m_{21}^2$ and ${sin}^2{\vartheta }_{12}\mathrm{\text{−}}{sin}^2{\vartheta }_{13}$ planes, as well as the marginal posterior probability distribution of ${sin}^2{\vartheta }_{13}$. We confirm the $1.2\sigma$ hint of ${\vartheta }_{13}>0$ found in [G. Fogli et al., Phys. Rev. Lett. 101, 141801 (2008).] from the analysis of solar and KamLAND neutrino data. We found that the statistical significance of the hint is reduced to about $0.8\sigma$ by the constraints on ${sin}^2{\vartheta }_{13}$ coming from atmospheric and long-baseline accelerator and reactor neutrino data, in agreement with [T. Schwetz, M. Tortola, and J. W. F. Valle, New J. Phys. 10, 113011 (2008).].

Three independent searches for an electric dipole moment (EDM) of the positive and negative muons have been performed, using spin precession data from the muon $g-2$ storage ring at Brookhaven National Laboratory. Details on the experimental apparatus and the three analyses are presented. Since the individual results on the positive and negative muons, as well as the combined result, $d_{\mu }=(0.0\pm 0.9)\times {10}^{-19}e\mathrm{cm}$, are all consistent with zero, we set a new muon EDM limit, $|d_{\mu }|<1.8\times {10}^{-19}e\mathrm{cm}$ (95% C.L.). This represents a factor of 5 improvement over the previous best limit on the muon EDM.

We obtain the most general spherically symmetric M2-branes and type-IIB strings, with ${\mathbb{R}}^{1,2}\times SO(8)$ and ${\mathbb{R}}^{1,1}\times SO(8)$ isometries, respectively. We find that there are 12 different classes of M2-branes, and we study their curvature properties. In particular, we obtain new smooth M2-brane wormholes that connect two asymptotic regions: one is flat and the other can be either flat or ${\mathrm{AdS}}_4\times S^7$. We find that these wormholes are traversable with certain timelike trajectories. We also obtain the most general Ricci-flat solutions in five dimensions with ${\mathbb{R}}^{1,1}\times SO(3)$ isometries.

In C. A. S. Almeida, R. Casana, M. M. Ferreira, Jr., and A. R. Gomes, Phys. Rev. D 79, 125022 (2009), the simplest Yukawa coupling $\eta \overline{\Psi }\varphi \chi \Psi$ was considered for a two-scalar-generated Bloch brane model. Fermionic resonances for both chiralities were obtained, and their appearance is related to branes with internal structure. Inspired on this result, we investigate the localization and resonance spectrum of fermions on a one-scalar-generated de Sitter thick brane with a class of scalar-fermion couplings $\eta \overline{\Psi }{\varphi }^k\Psi$ with positive odd integer $k$. A set of massive fermionic resonances for both chiralities is obtained when provided large coupling constant $\eta$. We find that the masses and lifetimes of left and right chiral resonances are almost the same, which demonstrates that it is possible to compose massive Dirac fermions from the left and right chiral resonances. The resonance with lower mass has longer lifetime. For a same set of parameters, the number of resonances increases with $k$ and the lifetime of the lower level resonance for larger $k$ is much longer than the one for smaller $k$.

We use a point-matching approach to numerically compute the Casimir interaction energy for a two perfect-conductor waveguide of arbitrary section. We present the method and describe the procedure used to obtain the numerical results. At first, our technique is tested for geometries with known solutions, such as concentric and eccentric cylinders. Then, we apply the point-matching technique to compute the Casimir interaction energy for new geometries such as concentric corrugated cylinders and cylinders inside conductors with focal lines.

We provide an algebraic study of the local composite operators $A_{\mu }{A}_{\nu }-\frac{{\delta }_{\mu \nu }}{d}{A}_{\kappa }^2$ and $A_{\mu }^2$, with $d=4$ the spacetime dimension. We prove that these are separately renormalizable to all orders in the Landau gauge. This corresponds to a renormalizable decomposition of the operator $A_{\mu }{A}_{\nu }$ into its trace and traceless parts. We present explicit results for the relevant renormalization group functions to three loop order, accompanied by various tests of these results. We then develop a formalism to determine the zero temperature effective potential for the corresponding condensates, and recover the already known result for $⟨A_{\mu }^2⟩\ne 0$, together with $⟨A_{\mu }{A}_{\nu }-\frac{{\delta }_{\mu \nu }}{d}{A}_{\kappa }^2⟩=0$, a nontrivial check that the approach is consistent with Lorentz symmetry. The formalism is such that it is readily generalizable to the finite temperature case, which shall allow a future analytical study of the electric-magnetic symmetry of the $⟨A_{\mu }^2⟩$ condensate, which received strong evidence from recent lattice simulations by Chernodub and Ilgenfritz, who related their results to three regions in the Yang-Mills phase diagram.

Spin foam models for quantum gravity are derived from lattice path integrals. The setting involves variables from both lattice BF theory and Regge calculus. The action consists in a Regge action, which depends on areas, dihedral angles and includes the Immirzi parameter. In addition, a measure is inserted to ensure a consistent gluing of simplices, so that the amplitude is dominated by configurations that satisfy the parallel transport relations. We explicitly compute the path integral as a sum over spin foams for a generic measure. The Freidel-Krasnov and Engle-Pereira-Rovelli models correspond to a special choice of gluing. In this case, the equations of motion describe genuine geometries, where the constraints of area-angle Regge calculus are satisfied. Furthermore, the Immirzi parameter drops out of the on-shell action, and stationarity with respect to area variations requires spacetime geometry to be flat.