We construct the nonlocal braneworld action in the two-brane Randall-Sundrum model in a holographic setup alternative to the Kaluza-Klein description: the action is written as a functional of the two metric and radion fields on the branes. This action effectively describes the dynamics of the gravitational field both on the branes and in the bulk in terms of the brane geometries directly accessible for observations. Its nonlocal form factors incorporate the cumulative effect of the bulk Kaluza-Klein modes. We also consider the reduced version of this action obtained by integrating out the fields on the negative-tension brane invisible from the viewpoint of the Planckian brane observer. This effective action features a nontrivial transition (AdS flow) between the local and nonlocal phases of the theory associated with the limits of small and large interbrane separation. Our results confirm a recently proposed braneworld scenario with diverging (repulsive) branes and suggest possible new implications of this phase transition in brane cosmology.

We study the cosmological consequences of nonconstant brane world moduli in five-dimensional brane world models with bulk scalars and two boundary branes. We focus on the case where the brane tension is an exponential function of the bulk scalar field, $U_b\propto \exp \left(\alpha \phi \right).\mathrm{}$ In the limit $\overrightarrow{\alpha }0,$ the model reduces to the two-brane model of Randall and Sundrum, whereas larger values of $\alpha$ allow for a less warped bulk geometry. Using the moduli space approximation we derive the four-dimensional low-energy effective action from a supergravity-inspired five-dimensional theory. For arbitrary values of $\alpha ,$ the resulting theory has the form of a biscalar-tensor theory. We show that, in order to be consistent with local gravitational observations, $\alpha$ has to be small (less than ${10}^{-2})$ and the separation of the branes must be large. We study the cosmological evolution of the interbrane distance and the bulk scalar field for different matter contents on each branes. Our findings indicate that attractor solutions exist which drive the moduli fields towards values consistent with observations. The efficiency of the attractor mechanism crucially depends on the matter content on each brane. In the five-dimensional description, the attractors correspond to the motion of the negative tension brane towards a bulk singularity, which signals the eventual breakdown of the four-dimensional description and the necessity of a better understanding of the bulk singularity.

We present our results of lattice calculations of B parameters, which parametrize $\Delta B=2\mathrm{}$ transition amplitudes together with the leptonic decay constant. Calculations are made in the quenched approximation at $\beta =5.7,$ 5.9, 6.0 and 6.1, using NRQCD action for heavy quarks and the $O\left(a\right)\mathrm{}$-improved Wilson action for light quarks. The operators are perturbatively renormalized including the correction of $O\left({\alpha }_s{/\left(\mathrm{aM}\right)\mathrm{}}^m\right)(m>~0).$ We examine the scaling behavior of B parameters, and discuss the systematic uncertainties based on the results with several different truncations of higher order terms in $1/M$ and ${\alpha }_s$ expansions. We find $B_{B_d}{(m}_b)=0.84\mathrm{}(3\left)\mathrm{}\right(5),$ $B_{B_s}{/B}_{B_d}{=1.020\mathrm{}\left(21\right)(}_{-16}^{+15\mathrm{}}{\left)\right(}_{-0}^{+5\mathrm{}})$ and $B_{S_s}{(m}_b{)=0.85\mathrm{}(1\left)\mathrm{}\right(5\left)\right(}_{-0}^{+1\mathrm{}})$ in the quenched approximation. The errors represent statistical and systematic errors as well as the uncertainty in the determination of strange quark mass.

We study QCD at nonzero temperature and baryon density in the framework of the analytic continuation from an imaginary chemical potential. We carry out simulations of QCD with four flavors of staggered fermions, and reconstruct the phase diagram in the temperature-imaginary $\mu$ plane. We consider Ansätze for the analytic continuation of the critical line and other observables motivated both by theoretical considerations and mean field calculations in four fermion models and random matrix theory. We determine the critical line, and the analytic continuation of the chiral condensate, up to ${\mu }_B\simeq 500\mathrm{MeV}.$ The results are in qualitative agreement with the predictions of model field theories, and consistent with a first order chiral transition. The correlation between the chiral transition and the deconfinement transition observed at $\mu =0\mathrm{}$ persists at nonzero density.

For semisimple groups, possibly multiplied by U(1)’s, the number of Yang-Mills gauge fields is equal to the number of generators of the group. In this paper, it is shown that, for nonsemisimple groups, the number of Yang-Mills fields can be larger. These additional Yang-Mills fields are not irrelevant because they appear in the gauge transformations of the original Yang-Mills fields. Such nonsemisimple Yang-Mills theories may lead to physical consequences worth studying. The nonsemisimple group with only two generators that do not commute is studied in detail.

Non-Abelian extensions of fluid dynamics, which can have applications to the quark-gluon plasma, are given. These theories are presented in a symplectic or Lagrangian formulation and involve a fluid generalization of the Kirillov-Kostant form well known in Lie group theory. In our simplest model the fluid flows with velocity $\mathbf{v}$ and, in the presence of non-Abelian chromoelectric or magnetic ${\mathbf{E}}^a/{\mathbf{B}}^a$ fields, the fluid feels a Lorentz force of the form $Q_a{\mathbf{E}}^a+(\mathbf{v}/c)\times Q_a{\mathbf{B}}^a,$ where $Q_a$ is a space-time local non-Abelian charge satisfying a fluid Wong equation $[{(D}_t+\mathbf{v}\cdot \mathbf{D})Q{]}_a=0\mathrm{}$ with gauge covariant derivatives.

We explore the 1/4 Bogomol’nyi-Prasad-Sommerfield (BPS) configurations of the supersymmetric gauge theories on ${\mathrm{R}}^{1+3}\times {\mathrm{S}}^1.$ The BPS bound for energy and the BPS equations are obtained and the characteristics of the BPS solutions are studied. These BPS configurations describe electrically charged calorons, which are constituted of dyons and carry linear momentum along the compact direction. We carry out various approaches to the single caloron case in the theory of the $\mathrm{SU}\mathrm{}\left(2\right)\mathrm{}$ gauge group.

Gravitational and other anomalies seen repeatedly in connection with solar eclipses have led to speculation about a possible gravitational shielding effect as the cause. Here we show that an unusual phenomenon that occurs only during solar eclipses, rapid air mass movement for the bulk of the atmosphere above normal cloud levels, appears to be a sufficient explanation for both the magnitude and behavior of the anomaly previously reported in these pages.

The electromagnetic (EM) current conservation and renormalizability of QCD are used to calculate the amplitude of energetic hadron (photon) diffraction into several jets with large relative transverse momenta off the nucleon (nucleus) Coulomb field. Numerical estimates of the ratio of EM and strong amplitudes show that within the kinematic range where the leading twist approximation for the strong amplitude is applicable, the EM contribution can be neglected. In $\mathrm{pA}$ scattering at the CERN Large Hadron Collider (LHC) and in the fragmentation of a photon into two jets in ultraperipheral $\mathrm{AA}$ collisions in the black limit (which may be realistic at the LHC) the EM contribution may win.

The ultracold neutron (UCN) storage experiment for searching for $n-\mathrm{n̄}$ oscillations is discussed. The figure of merit of the UCN experiment with respect to a beam experiment is considered. The effect of neutron collisions with the walls on the production rate of the $\mathrm{n̄}$ component is analyzed.

We reexamine questions concerning the contribution of the three-gluon Weinberg operator to the electric dipole moment of the neutron, and provide several QCD sum-rule-based arguments that the result is smaller than—but nevertheless consistent with—estimates which invoke naive dimensional analysis. We also point out a regime of the minimal supersymmetric standard model parameter space with light gluinos for which this operator provides the dominant contribution to the neutron electric dipole moment due to enhancement via the dimension five color electric dipole moment of the gluino.

We show that the Borel resummed perturbative static potential at $N_f=0\mathrm{}$ converges well, and is in remarkable agreement with the quenched lattice calculation at distances $1/r\gtrsim 660\mathrm{MeV}.$ This shows that Borel resummation is very good at handling the renormalon in the static potential (and in the pole mass), and allows one to use the pole mass in the perturbative calculation of heavy quark physics.

The spin structure of a system of quasifree fermions having a total angular momentum $J=1/2\mathrm{}$ is studied in a consistently covariant approach. Within this model the relations between the spin functions are obtained. Their particular cases are the sum rules of Wanzura and Wilczek, Efremov, Leader, and Teryaev, and Burkhardt and Cottingham and also the expression for the Wanzura-Wilczek twist 2 term $g_2^{\mathrm{WW}}.$ With the use of the proton valence quark distributions as input, the corresponding spin functions are obtained. The resulting structure functions $g_1$ and $g_2$ are quite compatible with the experimental data.

We compute the complete next-to-leading order SUSY-QCD corrections for the associated production of a charged Higgs boson with a top quark via bottom-gluon fusion. We investigate the applicability of the bottom parton description in detail. The higher order corrections can be split into real and virtual corrections for a general two Higgs doublet model and into additional massive supersymmetric loop contributions. We find that the perturbative behavior is well under control. The supersymmetric contributions consist of the universal bottom Yukawa coupling corrections and nonfactorizable diagrams. Over most of the relevant supersymmetric parameter space the Yukawa coupling corrections are sizable, while the remaining supersymmetric loop contributions are negligible.

In this paper we give a class of examples where the decays of the heavy Majorana neutrinos may violate CP even if there is no CP violation at low energies, i.e., where leptogenesis can take place without Majorana- or Dirac-type CP phases at low energies.

We present a series of measurements based on $K_{L,S}\to {\pi }^{+}{\pi }^{-}$ and $K_{L,S}\to {\pi }^0{\pi }^0$ decays collected in 1996–1997 by the $\mathrm{KTeV}$ experiment (E832) at Fermilab. We compare these four $\overrightarrow{K}\pi \pi$ decay rates to measure the direct $\mathrm{CP}$ violation parameter $\mathrm{Re}({\epsilon }^{\prime }/\epsilon )=(20.7\mathrm{}\pm 2.8)\times {10}^{-4}.$ We also test $\mathrm{CPT}$ symmetry by measuring the relative phase between the $\mathrm{CP}$ violating and $\mathrm{CP}$ conserving decay amplitudes for $\overrightarrow{K}{\pi }^{+}{\pi }^{-}$ $\left({\phi }_{+-}\right)$ and for $\overrightarrow{K}{\pi }^0{\pi }^0$ $\left({\phi }_{00}\right).\mathrm{}$ We find the difference between the relative phases to be $\Delta \phi \equiv {\phi }_{00}-{\phi }_{+-}=(+0.39\mathrm{}\pm 0.50)°,$ and the deviation of ${\phi }_{+-}$ from the superweak phase to be ${\phi }_{+-}-{\phi }_{\mathrm{SW}}=(+0.61\mathrm{}\pm 1.19)°;$ both results are consistent with $\mathrm{CPT}$ symmetry. In addition, we present new measurements of the $K_L$-$K_S$ mass difference and $K_S$ lifetime: $\Delta m=(5261\mathrm{}\pm 15)\times {10}^6ħ{\mathrm{s}}^{-1}$ and ${\tau }_S=(89.65\mathrm{}\pm 0.07)\times {10}^{-12}\mathrm{s}.$

We consider the lattice topological charge density introduced by Hasenfratz, Laliena, and Niedermayer and propose its eigenmode expansion as a tool to investigate the structure of topological charge fluctuations in QCD. The resulting effective density is built from local chiralities studied previously. At every order of the expansion, the density exactly sums up to the global topological charge, and the leading term describes the maximally smooth space-time distribution of charge relevant for propagating light fermions. We use this framework to demonstrate our previous suggestion that the bulk of the topological charge in QCD does not effectively appear in the form of quantized unit lumps. Our conclusion implies that it is unlikely that the mixing of “would-be” zero modes associated with such lumps is the prevalent microscopic mechanism for spontaneous chiral symmetry breaking in QCD. We also present the first results quantitatively characterizing the space-time behavior of effective densities. For coherent fluctuations contained in spherical regions, we find a continuous distribution of associated charges essentially ending at $\approx \mathrm{0.5.}$

Models for soft color interactions have been successful in describing and predicting diffractive hard scattering processes in $\mathrm{ep}$ collisions at DESY HERA and $p\overline{p}$ at the Fermilab Tevatron. Here we present new comparisons of the model to recent diffractive dijet data, also showing good agreement. The topical issue of diffractive Higgs boson production at the Tevatron and CERN LHC hadron colliders is further investigated. For $\overrightarrow{H}\gamma \gamma$ the irreducible background of prompt photon pairs from $q\overline{q}\to \gamma \gamma$ and $g\overrightarrow{g}\gamma \gamma$ is always dominating, implying that higher branching ratio decay modes of the Higgs boson have to be used. However, such prompt photons can be used to test the basic prediction for Higgs boson production since $g\overrightarrow{g}\gamma \gamma$ involves a quark loop diagram similar to $g\overrightarrow{g}H.\mathrm{}$

I study a fresh inflationary model with an increasing F-cosmological parameter. The model provides sufficient e-folds to solve the flatness or horizon problem and the density fluctuations agree with experimental values. The temperature increases during fresh inflation and reaches its maximum value when inflation ends. This fact could provide a transition between inflation and the radiation-dominated epoch, once inflation ends. I find that entropy perturbations always remain below ${10}^{-4}$ during fresh inflation and become negligible when fresh inflation ends. Hence, the adiabatic fluctuations dominate the primordial spectrum at the end of fresh inflation.

We analyze the dynamical stability of black hole solutions in self-gravitating nonlinear electrodynamics with respect to arbitrary linear fluctuations of the metric and electromagnetic field. In particular, we derive simple conditions on the electromagnetic Lagrangian which imply linear stability in the domain of outer communication. We show that these conditions hold for several of the regular black hole solutions found by Ayón-Beato and García.