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The formulation of quasilocal conformal Killing horizons (CKH) is extended to include rotation. This necessitates that the horizon be foliated by 2-spheres which may be distorted. Matter degrees of freedom which fall through the horizon are represented by a real scalar field. We show that these rotating CKHs also admit a first law in differential form. [ABSTRACT FROM AUTHOR]

We examine quintessence models for dark energy in which the scalar field ɸ evolves near the vicinity of a local maximum or minimum in the potential V(ɸ), so that V(ɸ) can be approximated by a quadratic function of ɸ with no linear term. We generalize previous studies of this type by allowing the initial value of dɸ/dt to be nonzero. We derive an analytic approximation for w(a) and show that it is in excellent agreement with numerical simulations for a variety of scalar field potentials having local minima or maxima. We derive an upper bound on the present-day value of w as a function of the other model parameters and present representative limits on these models from observational data. This work represents a final generalization of previous studies using linear or quadratic approximations for V(ɸ). [ABSTRACT FROM AUTHOR]

If vector type perturbations are present in the primordial plasma before recombination, the generation of magnetic fields is known to be inevitable through the Harrison mechanism. In the context of the standard cosmological perturbation theory, nonlinear couplings of first-order scalar perturbations create second-order vector perturbations, which generate magnetic fields. Here we reinvestigate the generation of magnetic fields at second-order in cosmological perturbations on the basis of our previous study, and extend it by newly taking into account the time evolution of purely second-order vector perturbations with a newly developed second-order Boltzmann code. We confirm that the amplitude of magnetic fields from the product-terms of the first-order scalar modes is consistent with the result in our previous study. However, we find, both numerically and analytically, that the magnetic fields from the purely second-order vector perturbations partially cancel out the magnetic fields from one of the product-terms of the first-order scalar modes, in the tight coupling regime in the radiation dominated era. Therefore, the amplitude of the magnetic fields on small scales, k≳10 hMpc-1, is smaller than the previous estimates. The amplitude of the generated magnetic fields at cosmological recombination is about Brec = 5.0×10-24 Gauss on k = 5.0×10-1 hMpc-1. Finally, we discuss the reason for the discrepancies that exist in estimates of the amplitude of magnetic fields among other authors. [ABSTRACT FROM AUTHOR]

We consider a model of the early Universe which consists of two scalar fields: the inflaton and a second field which drives the stabilization of the Planck mass (or gravitational constant). We show that the nonminimal coupling of this second field to the Ricci scalar sources a nonadiabatic pressure perturbation. By performing a fully numerical calculation, we find, in turn, that this boosts the amplitude of the primordial power spectrum after inflation. [ABSTRACT FROM AUTHOR]

The Balitsky-Fadin-Kuraev-Lipatov (BFKL) approach for the investigation of semihard processes is plagued by large next-to-leading corrections, both in the kernel of the universal BFKL Green's function and in the process-dependent impact factors, as well as by large uncertainties in the renormalization scale setting. All that calls for an optimization procedure of the perturbative series. In this respect, one of the most common methods is the Brodsky-Lepage-Mackenzie (BLM) one, which eliminates the renormalization scale ambiguity by absorbing the nonconformal β0 terms into the running coupling. In this paper, we apply the BLM scale setting procedure directly to the amplitudes (cross sections) of several semihard processes. We show that, due to the presence of β0 terms in the next-to-leading expressions for the impact factors, the optimal renormalization scale is not universal but depends both on the energy and on the type of process in question. [ABSTRACT FROM AUTHOR]

It is shown that the causal structure associated to string like solutions of the Faddeev-Niemi model is described by an effective metric. Remarkably, the surfaces characterizing the causal replacement depend on the energy momentum tensor of the background soliton and carry implicitly a topological invariant π3(S2). As a consequence, it follows that the preimage curves in R3 nontrivially define directions where the cones remain unchanged. We expect that these early results may be of importance in understanding time dependent solutions (collisions/scatterings) numerically or analytically. [ABSTRACT FROM AUTHOR]

We present rotating wormhole solutions in general relativity, which are supported by a phantom scalar field. These solutions evolve from the static Ellis wormhole, when the throat is set into rotation. As the rotational velocity increases, the throat deforms until, at a maximal value of the rotational velocity, an extremal Kerr solution is encountered. The rotating wormholes attain a finite mass and quadrupole moment. They exhibit ergospheres and possess bound orbits. [ABSTRACT FROM AUTHOR]

We study a model of n coupled scalar fields in Minkowski spacetime where all masses degenerate, which is considered as a toy model of polycritical gravity on AdS spacetime. We quantize this model within the Becchi-Rouet-Stora-Tyutin (BRST) scheme by introducing n Faddeev-Popov (FP) ghost fields. Extending a BRST quartet generated by two scalars and two FP ghosts to n scalars and n FP ghosts, there remains a physical subspace with positive norm for odd n, but there exists only the vacuum for even n. This clearly shows a non-triviality of odd-higher order derivative scalar field theories. This is helpful to understand the truncation mechanism which is used to obtain a unitary conformal field theory dual to linearized polycritical gravity. It turns out that the truncation mechanism is nothing but a general quartet mechanism appeared when introducing the FP ghost action. [ABSTRACT FROM AUTHOR]

Force between static point particles coupled to a classical ultramassive scalar field is calculated. The field potential is proportional to the modulus of the field. It turns out that the force exactly vanishes when the distance between the particles exceeds certain finite value. Moreover, each isolated particle is surrounded by a compact cloud of the scalar field that completely screens its scalar charge. [ABSTRACT FROM AUTHOR]

We discuss building models for nucleon generalized parton distributions H and E that are based on the formalism of double distributions (DDs). We found that the usual "DD + D-term" construction should be amended by an extra term, ξE+¹ (x, &#958) built from the α/β moment of the DD e(β, β) that generates generalized parton distribution E(x, ξ). Unlike the D term, this function has support in the whole -- 1 = x = 1 region, and in general does not vanish at the border points │x│ =ξ [ABSTRACT FROM AUTHOR]

We provide a status report on the advances in blocking-inspired supersymmetric actions. This is done with the example of interacting supersymmetric quantum mechanics as well as the Wess-Zumino model. We investigate in particular the implications of a nontrivial realization of translational symmetry on the lattice in this approach. We also discuss the locality of symmetry generators. [ABSTRACT FROM AUTHOR]

We consider a generalization of the Thirring model in 2 + 1 dimensions at finite density. We employ stochastic quantization and check for the applicability in the finite density case to circumvent the sign problem. To this end we derive analytical results in the heavy dense limit and compare with numerical ones obtained from a complex Langevin evolution. Furthermore, we make use of indirect indicators to check for incorrect convergence of the underlying complex Langevin evolution. The method allows the numerical evaluation of observables at arbitrary values of the chemical potential. We evaluate the results and compare to the (0 + l)-dimensional case. [ABSTRACT FROM AUTHOR]

We present a spinning hairy black hole in gravity minimally coupled to a self-interacting real scalar field in three spacetime dimensions. The black hole is characterized by having a single horizon that encloses a curvature singularity and the scalar field is regular everywhere. The maas and angular momentum are shown to be finite. The presence of a scalar field with a slower falloff at infinity leads an anti-dc Sitter asymptotic behavior that differs from the one found by Brown and Henneaux but has the same symmetry group as in pure gravity. A scalar soliton, which is a finite mass regular solution devoid of integration constants, plays the role of the ground state. The existence of this soliton is the key to deriving the semiclassical entropy of the rotating hairy black hole using the counting of microscopic states provided by the Cardy formula. [ABSTRACT FROM AUTHOR]

We study vortexlike solutions to the Lifshitz-Chern-Simons theory. We find that such solutions exist and have a logarithmically divergent energy, which suggests that a Kostelitz-Thouless transition may occur, in which voxtex-antivortex pairs are created above a critical temperature. Following a suggestion made by Callan and Wilzcek for the global U(l) scalar field model, we study vortex solutions of the Lifshitz-Chern-Simons model formulated on the hyperbolic plane, finding that, as expected, the resulting configurations have finite energy. For completeness, we also explore Lifshitz-Chern-Simons vortex solutions on the sphere. [ABSTRACT FROM AUTHOR]

Using a nonperturbative approximation for the partition function of a complex scalar model, which features spontaneous symmetry breaking, we explicitly derive the flattening of the effective potential in the region limited by the minima of the bare potential. This flattening occurs in the limit of infinite volume and is a consequence of the summation over the continuous set of saddle points which dominate the partition function. We also prove the convexity of the effective potential and generalize the Maxwell construction for scalar theories with 0(N) symmetry. Finally, we discuss why the flattening of the effective potential cannot occur in the Abelian Higgs theory. [ABSTRACT FROM AUTHOR]

The modified scalar boson propagator due to the presence of a hyperplane semitransparent mirror is computed. From this, the classical interaction between static charges and the mirror is investigated employing delta-like potentials and sources. Although the calculations for hyperplane mirrors are performed in arbitrary dimensions, and in a completely general way, it is shown that the results give rise to the usual image method as a particular case. The interaction between a point-like mirror and a point-like source is also considered in 3 + 1 dimensions, where a central 1/R² attractive potential is also obtained as a special case. [ABSTRACT FROM AUTHOR]

Quantum mechanics with a generalized uncertainty principle arises through a representation of the commutator [x, p[ = if(p). We apply this deformed quantization to free scalar field theory for f± = 1 ± βp². The resulting quantum field theories have a rich fine scale structure. For small wavelength modes, the Green's function for f+ exhibits a remarkable transition from Lorentz to Galilean invariance, whereas for f- such modes effectively do not propagate. For both cases Lorentz invariance is recovered at long wavelengths. [ABSTRACT FROM AUTHOR]

As a toy model of a gapped system, we investigate the entanglement entropy of a massive scalar field in 1 + 1 dimensions at nonzero temperature. In a small mass m and temperature T limit, we put upper and lower bounds on the two largest eigenvalues of the covariance matrix used to compute the entanglement entropy. We argue that the entanglement entropy has e-m/T scaling in the limit T ⪡m. We comment on the relation between our work and the Ryu-Takayanagi proposal for computing the entanglement entropy holographically. [ABSTRACT FROM AUTHOR]

It is often the case that scalar fields are produced in the early Universe in the form of coherent oscillation. These scalar fields may have huge abundances and affect the evolution of the Universe. In particular, if the lifetime is long enough, they may cause cosmological disasters. We revisit the issue of coherent oscillation of the scalar field when it couples with another oscillating scalar field, and find a situation that the abundance, or the amplitude of the oscillation, is significantly reduced by a variant type of the adiabatic suppression mechanism. As a concrete example, it is applied to the saxion, a flat direction in the supersymmetric axion model, and we show that the cosmological saxion problem is solved in a particular setup. [ABSTRACT FROM AUTHOR]

We analyze the dynamical system defined by a universe filled with a barotropic fluid plus a scalar field with modified kinetic term of the form £ = F(X) - V(ø). After a suitable choice of variables that allows us to study the phase space of the system, we obtain the critical points and their stability. We find that some of them reduce to the ones defined for the canonical case when F(X) = X. We also study the field energy conditions to have a nonsingular bounce. [ABSTRACT FROM AUTHOR]

The Korteweg-de Vries equation is a nonlinear wave equation that has played a fundamental role in diverse branches of mathematical and theoretical physics. In the present paper, we consider its significance to cosmology. It is found that the Korteweg-de Vries equation arises in a number of important scenarios, including inflationary cosmology, the cyclic universe, loop quantum cosmology and braneworld models. Analogies can be drawn between cosmic dynamics and the propagation of the solitonic wave solution to the equation, whereby quantities such as the speed and amplitude profile of the wave can be identified with cosmological parameters such as the spectral index of the density perturbation spectrum and the energy density of the universe. The unique mathematical properties of the Schwarzian derivative operator are important to the analysis. A connection with dark solitons in Bose-Einstein condensates is briefly discussed. [ABSTRACT FROM AUTHOR]

We discuss the damping of tensor modes due to anisotropic stress in inflation. The effect is negligible in standard inflation and may be significantly large in inflation models which involve drastic production of free-streaming particles. [ABSTRACT FROM AUTHOR]

The Campanelli-Lousto solutions of Brans-Dicke theory, usually reported as black holes, are reconsidered and shown to describe, according to the values of a parameter, wormholes or naked singularities. The veiled Schwarzschild metric recently used as an example to discuss conformai frames and their equivalence corresponds to a special case of the Campanelli-Lousto metric. The conformai cousins of these solutions, and of the Riegert black hole solution of conformally invariant Weyl theory, are analyzed, leading to a word of caution when physically interpreting spacetimes generated via conformai transformations from known seed solutions. [ABSTRACT FROM AUTHOR]

We discuss the set of constraints for Einstein-aether theories, comparing the flat background case with what is expected when the gravitational fields are dynamic. We note potential pathologies occurring in the weak gravitational field limit for some of the Einstein-aether theories. [ABSTRACT FROM AUTHOR]

We discuss evolution of density perturbations in cosmological models which admit finite scale factor singularities. After solving the matter perturbations equations we find that there exists a set of parameters which admits a finite scale factor singularity in future and instantaneously recover matter density evolution history which is indistinguishable from the standard ACDM scenario. [ABSTRACT FROM AUTHOR]

A coding error was found in our original version of numerical-relativity code SACRA. We correct the results of [M. Shibata, K. Kyutoku, T. Yamamoto, and K. Taniguchi, Phys. Rev. D 79, 044030 (2009).] by simulations of the improved accuracy. [ABSTRACT FROM AUTHOR]

In this paper, we categorize nonrotating black hole spacetimes based on their pole structure, and in each of these categories we determine whether the WKB approximation is a valid approximation for calculating the asymptotic quasinormal modes. We show that Schwarzschild black holes with the Gauss-Bonnet (G-B) correction belong to the category in which the WKB approximation is invalid for calculating these modes. In this context, we further discuss and clarify some of the ambiguity in the literature surrounding a validity condition provided for the WKB approximation. [ABSTRACT FROM AUTHOR]

Using the noncommutative deformed canonical commutation relations proposed by Carmona et al. [J. M. Carmona, J. L. Cortés, J. Gamboa, and F. Méndez, J. High Energy Phys. 03 (2003) 058.][J. Gamboa, J. Lopéz-Sarrion, and A. P. Polychronakos, Phys. Lett. B 634, 471 (2006).] [J. M. Carmona, J.L. Cortés, Ashok Das, J. Gamboa, and F. Méndez, Mod. Phys. Lett. A 21, 883 (2006).], a model describing the dynamics of the noncommutative complex scalar field is proposed. The noncommutative field equations are solved, and the vacuum energy is calculated to the second order in the parameter of noncommutativity. As an application to this model, the Casimir effect, due to the zero-point fluctuations of the noncommutative complex scalar field, is considered. It turns out that in spite of its smallness, the noncommutativity gives rise to a repulsive force at the microscopic level, leading to a modified Casimir potential with a minimum at the point amin = √5/84&pgr;&thetas;. [ABSTRACT FROM AUTHOR]

(n + 2)-dimensional Lorentzian spacetime, which admits irreducible Killing tensors of rank up to n, is constructed by applying the Eisenhart lift to the Calogero model. [ABSTRACT FROM AUTHOR]

Multisoliton form factors in sine-Gordon theory from the bootstrap are compared to finite-volume matrix elements computed using the truncated conformai space approach. We find convincing agreement, and resolve most of the issues raised in a previous work. [ABSTRACT FROM AUTHOR]

An explicit and detailed investigation about the two-dimensional single axial-vector (AVV) triangle is performed. Such a perturbative amplitude is related to the anomalous axial-vector (AV) one through contractions with external momenta. Given this fact, before considering such a triangle we must give a clear point of view for the AV amplitude. Such a point of view is constructed within the context of an alternative strategy to handle the divergences typical of perturbative solutions of quantum field theory. In this procedure all amplitudes in all theories, formulated in odd and even space-time dimensions, renormalizable or not, are treated in an absolutely identical way. The ambiguities are automatically eliminated and the symmetry relations preserved. The well-known divergent anomalous amplitudes are correctly described, in a predictive scenario. After performing, in a very detailed way, all the calculations involved we conclude that the same phenomenon occurring in the AV amplitude is also present in the finite AVV triangle. The conclusion gives support to the thesis that the phenomenon is present in all pseudoamplitudes in a chain where the divergent AV one is only the most simple structure. The same must occur in all even space-time dimensions. In particular, the single and triple four-dimensional box amplitudes must exhibit anomalies too. A conclusive investigation is allowed due to the special features of the adopted procedure where regularization is completely avoided and an adequate systematization for the finite parts is introduced. [ABSTRACT FROM AUTHOR]

We studied different levels of resummations of the exactly solvable Bloch-Nordsieck model in order to be able to compare the approximations with an exact result. We studied one-loop perturbation theory, two-particle-irreducible resummation and Schwinger-Dyson equations truncated in a way to maintain Ward identities. At all levels we carefully performed renormalization. We found that although the two-particle-irreducible resummation does not exhibit infrared sensitivity at the mass shell, as the one-loop perturbation theory does, it is still far from the exact solution. The method of truncated renormalized Schwinger-Dyson equations, however, is exact in this model, so it provides a new way of solving the Bloch-Nordsieck model. This method may also be generalized to other, more complicated theories. [ABSTRACT FROM AUTHOR]

We attempt a critical reconsideration of "detailed balance" as a principle that can be used to restrict the proliferation of couplings in Horava-Lifshitz gravity. We reexamine the shortcomings that have been usually associated with it in the literature and we argue that easy remedies can be found for all of them within the framework of detailed balance, and that the most persistent of them are actually related to projectability. We show that, once projectability is abandoned, detailed balance reduces the number of independent couplings by roughly an order of magnitude and imposes only one restriction that constitutes a phenomenological concern: the size of the (bare) cosmological constant is unacceptably large. Remarkably, this restriction (which is present in the projectable version as well) has been so far underappreciated in the literature. Optimists might prefer to interpret it as a potential blessing in disguise, as it allows one to entertain the idea of a miraculous cancellation between the bare cosmological constant and the (still poorly understood) vacuum energy contribution. [ABSTRACT FROM AUTHOR]

We present a simple and efficient method to compute the superhorizon evolution of the spectral index in multifield inflationary models, using transport equation techniques. We illustrate the evolution of n, with time for various interesting potentials. [ABSTRACT FROM AUTHOR]

The experimental data on the processes ππ→ ππ, KK, ηη, ηη' in the IGJPC = 0+0++ channel have been jointly analyzed to study the status and nature of the /0. The method of analysis is based on analyticity and unitarity and uses an uniformization procedure. Some spectroscopic implications from results of the analysis are discussed. [ABSTRACT FROM AUTHOR]

A Bayesian reference analysis of a typical scenario of high energy physics has recently been performed [Phys. Rev. D 82, 034002 (2010)]. The reference prior with partial information (and hence also the posterior) were found to depend on the sequence of subsets of the parameter space used for a normalization process. A particular choice of the subsets leading to a proper posterior was advocated. Here it is shown that this choice differs from the natural sequence of subsets in the "original parametrization" of the problem, which has been generally recommended elsewhere. Although this questions the manner in which the commented result was obtained, the result itself is corroborated because the present derivation based on a different argument yields a reference prior of the same functional form. [ABSTRACT FROM AUTHOR]

We study the polarized Drell-Yan processes from the collision of two spin-1/2 hadrons at order 1/Q based on the framework of transverse-momentum dependent factorization. We give the complete twist- three results of total 16 independent structure functions in terms of twist-two and twist-three transverse-momentum dependent distribution functions. [ABSTRACT FROM AUTHOR]

We show that the Kobayashi-Maskawa (KM) parametrization of the 3 x 3 lepton flavor mixing matrix is a useful language to describe the phenomenology of neutrino oscillations. In particular, it provides us with a convenient way to link the genuine flavor mixing parameters (θ1, θ2, θ3 and δKM) to their effective counterparts in matter (θ̃1, θ̃2, θ̃3 and δ̃KM). We rediscover the Toshev-like relation sinδ̃KM sin2θ̃2 = sinδKM sin2θ2 in the KM parametrization. We make reasonable analytical approximations to the exact relations between the genuine and matter-corrected flavor mixing parameters in two different experimental scenarios: (a) the neutrino beam energy E is above O(1) GeV and (b) E is below O(1) GeV. As an example, the probability of vμ → ve oscillations and CP-violating effects are calculated for the upcoming NovA and Hyper-K experiments. [ABSTRACT FROM AUTHOR]

Harrison, Perkins and Scott have proposed simple charged lepton and neutrino mass matrices that lead to the tribimaximal mixing UTBM. We consider in this work an extension of the mass matrices so that the leptonic mixing matrix becomes Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed., where Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. is a unitary matrix needed to diagonalize the charged lepton mass matrix and W measures the deviation of the neutrino mixing matrix from the bimaximal form. Hence, corrections to UTBM arise from both charged lepton and neutrino sectors. Following our previous work to assume a Qin-Ma-like parametrization VQM for the charged lepton mixing matrix Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. in which the CP-odd phase is approximately maximal, we study the phenomenologi implications in two different scenarios: Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. and Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed.. We find that the latter is preferable, though both scenarios are consistent with the data within 3σ ranges. The predicted reactor neutrino mixing angle θ13 in both scenarios is consistent with the recent T2K and MINOS data. The leptonic CP violation characterized by the Jarlskog invariant J is generally of order 10-2. [ABSTRACT FROM AUTHOR]

Using a data sample of 2.59 x 107 ψ(2S) decays obtained with the CLEO-c detector, we perform amplitude analyses of the complementary decay chains ψ(2S) → γ χc1; χc1 → ηπ+π- and ψ(2S) → γ χc1; χc1 → η'π+π-. We find evidence for an exotic P-wave η' π amplitude, which, if interpreted as resonance, would have parameters consistent with the π1(1600) state reported in other production mechanisms. We also make the first observation of the decay a0 (980) → η 'π and measure the ratio of branching fractions B(a0(980) → η 'π) / B(a0(980) → η π) = 0.064 ± 0.014 ± 0.014. The π π spectrum produced with a recoiling η is compared to that with η' recoil. [ABSTRACT FROM AUTHOR]

A model-independent search for direct CP violation in the Cabibbo-suppressed decay D+ → K- K + π+ in a sample of approximately 370000 decays is carried out. The data were collected by the LHCb experiment in 2010 and correspond to an integrated luminosity of 35 pb-1. The normalized Dalitz plot distributions for D+ and D- are compared using four different binning schemes that are sensitive to different manifestations of CP violation. No evidence for CP asymmetry is found. [ABSTRACT FROM AUTHOR]

An electron antineutrino mass has been measured in tritium β decay in the Troitsk v-mass experiment. The setup consists of a windowless gaseous tritium source and an electrostatic electron spectrometer. The whole data set acquired from 1994 to 2004 was reanalyzed. A thorough selection of data with the reliable experimental conditions has been performed. We checked every known systematic effect and obtained the following experimental estimate for neutrino mass squared Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed.. This gives an experimental upper sensitivity limit of mv < 2.2 eV, 95% C.L. and upper limit estimates mv < 2.12 eV, 95% C.L. for Bayesian statistics and mv < 2.05 eV, 95% C.L. for the Feldman and Cousins approach. [ABSTRACT FROM AUTHOR]

We report updated branching fraction measurements of the color-suppressed decays B̄0 → D0 π0, D*0 π0, D0 η, D*0 η, D0 ω, D*0 ω, D0 η', and D*0 η'. We measure the branching fractions (x 10-4): B(B̄0 → D0 π0 = 2.69 ± 0.09 ± 0.13, B(B̄0 → D*0 π0 = 3.05 ± 0.14 ± 0.28, B(B̄0 → D0 η) = 2.53 ± 0.09 ± 0.11, B(B̄0 → D*0 η) = 2.69 ± 0.14 ± 0.23, B(B̄0 → D0 ω) = 2.57 ± 0.11 ± 0.14, B(B̄0 → D*0 ω) = 4.55 ± 0.24 ± 0.39, B(B̄0 → D0 η') = 1.48 ± 0.13 ± 0.07, and B(B̄0 → D*0 η') = 1.49 ± 0.22 ± 0.15. We also present the first measurement of the longitudinal polarization fraction of the decay channel D*0ω fL = (66.5 ± 4.7 ± 1.5)%. In the above, the first uncertainty is statistical and the second is systematic. The results are based on a sample of (454 ± 5) x 106 BB̄ pairs collected at the Y(4S) resonance, with the BABAR detector at the PEP-II storage rings at SLAC. The measurements are the most precise determinations of these quantities from a single experiment. They are compared to theoretical predictions obtained by factorization, Soft Collinear Effective Theory (SCET) and perturbative QCD (pQCD). We find that the presence of final state interactions is favored and the measurements are in better agreement with SCET than with pQCD. [ABSTRACT FROM AUTHOR]

We report on the high statistics two-pion correlation functions from p p collisions at √s = 0.9 TeV and √s = 7 TeV, measured by the ALICE experiment at the Large Hadron Collider. The correlation functions as well as the extracted source radii scale with event multiplicity and pair momentum. When analyzed in the same multiplicity and pair transverse momentum range, the correlation is similar at the two collision energies. A three-dimensional femtoscopic analysis shows an increase of the emission zone with increasing event multiplicity as well as decreasing homogeneity lengths with increasing transverse momentum. The latter trend gets more pronounced as multiplicity increases. This suggests the development of space-momentum correlations, at least for collisions producing a high multiplicity of particles. We consider these trends in the context of previous femtoscopic studies in high-energy hadron and heavy-ion collisions and discuss possible underlying physics mechanisms. Detailed analysis of the correlation reveals an exponential shape in the outward and longitudinal directions, while the sideward remains a Gaussian. This is interpreted as a result of a significant contribution of strongly decaying resonances to the emission region shape. Significant nonfemtoscopic correlations are observed, and are argued to be the consequence of "mini-jet"-like structures extending to low Pt. They are well reproduced by the Monte-Carlo generators and seen also in π+ π- correlations. [ABSTRACT FROM AUTHOR]

We show that the discovery channel for dark matter (DM) production at colliders can be through flavor violating interactions resulting in a novel signature of a single top and large missing transverse energy. We discuss several examples where the production of DM is dominated by flavor violating couplings: minima llavor violating models with a large bottom Yukawa, models with horizontal symmetries, and DM nontrivial flavor group representations. Discovery at the 7 TeV LHC with a few fb-1 may already be possible. [ABSTRACT FROM AUTHOR]

The physical meaning of structure scalars is analyzed for charged dissipative spherical fluids and for neutral dust in the presence of cosmological constant. The role played by such factors in the structure scalars is clearly brought out and physical consequences are discussed. Particular attention needs to be paid to the changes introduced by the above mentioned factors in the inhomogeneity factor and the evolution of the expansion scalar and the shear tensor. [ABSTRACT FROM AUTHOR]

The linearized Einstein field equations with the renormalized stress tensor of a massless quantum scalar field as source are solved in the 4-dimensional spacetime near an infinite plane boundary. The motion of particles and light is investigated disclosing a variety of effects. For instance, it is shown that light rays initially parallel to the boundary do not bend. On the other hand, under the same initial conditions, particles will be affected by the presence of the quantum field, being accelerated toward the plane boundary or departing from it depending on the value of the curvature coupling parameter ξ. It is suggested that ξ can be set by measuring the spectral deviation of a light ray travelling perpendicularly to the boundary. [ABSTRACT FROM AUTHOR]

Many theoretical attempts toward reconstructing the potential and dynamics of the scalar fields have been done in the literature by establishing a connection between holographic/agegraphic energy density and a scalar-field model of dark energy. However, in most of these cases the analytical form of the potentials in terms of the scalar field have not been reconstructed due to the complexity of the equations involved. In this paper, by taking Hubble radius as system's IR cutoff, we are able to reconstruct the analytical form of the potentials as a function of scalar field, namely, V = V(φ) as well as the dynamics of the scalar fields as a function of time, namely, φ = φ (t), by establishing the correspondence between holographic energy density and quintessence, tachyon, K-essence, and dilaton energy density in a fiat Friedmann-Robertson-Walker universe. [ABSTRACT FROM AUTHOR]

We discuss several features of the propagation of perturbations in nonlinear scalar field theories using the effective metric. It is shown that the effective metric can be classified according to whether the gradient of the scalar field is timelike, null, or spacelike, and this classification is illustrated with two examples. We shall also show that different signatures for the effective metric are allowed. [ABSTRACT FROM AUTHOR]

If the generalized dynamics of K field theories (i.e., field theories with a nonstandard kinetic term) is taken into account, then the possibility of so-called twinlike models opens up, that is, of different field theories which share the same topological defect solution with the same energy density. These twinlike models were first introduced in [M. Andrews, M. Lewandowski, M. Trodden, and D. Wesley, Phys. Rev. D 82, 105006 (2010)], where the authors also considered possible cosmological implications and gave a geometric characterization of twinlike models. A further analysis of the twinlike models was accomplished in [D. Bazeia, J. D. Dantas, A. R. Gomes, L. Losano, and R. Menezes, Phys. Rev. D 84, 045010 (2011)], with the help of the first order formalism, where also the case with gravitational self-interaction was considered. Here we show that by combining the geometric conditions of [M. Andrews, M. Lewandowski, M. Trodden, and D. Wesley, Phys. Rev. D 82, 105006 (2010)], with the first order formalism of [D. Bazeia, J.D. Dantas, A.R. Gomes, L. Losano, and R. Menezes, Phys. Rev. D 84, 045010 (2011)], one may easily derive a purely algebraic method to explicitly calculate an infinite number of twin field theories for a given theory. We determine this algebraic construction for the cases of scalar field theories, supersymmetric scalar field theories, and self-gravitating scalar fields. Further, we give several examples for each of these cases. [ABSTRACT FROM AUTHOR]