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Abstract: The analyzability of the universe into subsystems requires a concept of the “independence” of the subsystems, of which the relativistic quantum world supports many distinct notions which either coincide or are trivial in the classical setting. The multitude of such notions and the complex relations between them will only be adumbrated here. The emphasis of the discussion is placed upon the warrant for and the consequences of a particular notion of subsystem independence, which, it is proposed, should be viewed as primary and, it is argued, provides a reasonable framework within which to sensibly speak of relativistic quantum subsystems. [Copyright &y& Elsevier]

Like other interfaces, equilibrium grain boundaries are smooth at low temperature and rough at high temperature; however, little attention has been paid to roughening except for faceting boundaries. Using molecular dynamics simulations of face-centered cubic Ni, we studied two closely related grain boundaries with different boundary planes. In spite of their similarity, their boundary roughening temperatures differ by several hundred degrees, and boundary mobility is much larger above the roughening temperature. This has important implications for microstructural development during metallurgical processes. [Copyright &y& Elsevier]

Insufficient bonding between multi-wall carbon nanotubes (MWCNTs) and the matrix reduces the effectiveness of MWCNT reinforcements in sol–gel silica dielectric composites. This paper investigates the efficacy of various surfactants in improving the bonding through morphological and mechanical characterization of MWCNT-reinforced sol–gel silica dielectric films. It is found that use of some surfactants while dispersing MWCNTs improves the modulus and hardness. The improved mechanical properties possibly reduce the delamination problem of Cu/low-k films during flip-chip packaging and wirebonding. [Copyright &y& Elsevier]

The reported experimentally determined bulk modulus for Cr2AlC is 28–40% lower than the value obtained by ab initio calculations. To identify the origin of this extensive difference between theory and experiment, the elastic modulus of thin Cr2AlC films was measured by nanoindentation and the temperature dependence thereof was studied by ab initio molecular dynamics. Our experimental and theoretical elastic modulus data are within the expected error margin and hence consistent with the published ab initio data. [Copyright &y& Elsevier]

The present study shows that nanostructure–dendrite composites successfully synthesize in the Fe–Zr binary eutectic system, exhibiting a better combination of strength and plasticity than bulk metallic glass or nanograined materials. The composites composed of microscaled dendritic phases (Fe2Zr or α-Fe) and nanoscaled lamellar eutectic matrix (Fe2Zr+α-Fe) exhibit high compressive strength (1.8–2.6GPa) and plasticity (2.5–12%) under compression. In particular, the plasticity can be improved when coarsened ductile dendritic phases are reinforced in the fine-scaled lamellar eutectic matrix. [Copyright &y& Elsevier]

Spheroidal microstructures suitable for thixoforming, can be formed by a variety of techniques. From optical microscopy and electron backscattered diffraction observations, the mechanism of formation of such microstructure in an Al–Si alloy conditioned by the so-called deformation–recrystallization technique is described as an internal partition of the deformed dendrites. During heating and partial remelting, low angle boundaries turn into high angle boundaries, whose penetration by the liquid is energetically favorable, thus leading to a dispersion of spheroidal Al-α particles. [Copyright &y& Elsevier]

Quantitative atomic structure and phase analysis in the titanium aluminide intermetallic system of composition Ti–45Al–7.5Nb–0.5C (at.%) was conducted in situ by use of high-energy X-ray diffraction from a synchrotron and evaluated using the Rietveld method, implementing a model for atomic order in the α-phase which describes the order to disorder transition α2 →α at the eutectoid temperature. The order parameter exhibits unexpected behavior and is entangled with the competition of different kinetic processes. [Copyright &y& Elsevier]

Atomistic simulations using an EAM potential are carried out to investigate the first stages of plasticity in aluminium slabs, in particular the effect of both temperature and step geometry on the nucleation of dislocations from surface steps. Temperature is shown to significantly reduce the elastic limit, and to activate the nucleation of dislocation half-loops. Twinning occurs by successive nucleations in adjacent glide planes. The presence of a kinked step is shown to have no influence on the nucleation mechanisms. [Copyright &y& Elsevier]

This paper presents a creep–fatigue-interacted lifetime prediction methodology based on continuum damage mechanics for the Ni-based superalloy under cyclic loading at high temperature. A unified life estimation model has been developed enabling stress–strain curves and cumulative damage to be predicted. Four types of low cycle fatigue tests were carried out at 650°C. The effects of the levels of strain range and strain hold time together with frequency characteristics of fatigue behavior on the lifetime were investigated. [Copyright &y& Elsevier]

A series of wide band gap semiconductors, CuAlS2+x , with a chalcopyrite structure were synthesized in bulk form by spark plasma sintering. p-type conductions for all samples were confirmed by positive Seebeck and Hall coefficients. For excess S introduced into the system, the carrier concentration was highly enhanced, reaching 6.9×1019 cm−3 for the 10% doped sample, which results in a high conductivity of 4.6Scm−1 without decreasing the bang gap. [Copyright &y& Elsevier]

TiB2 particles were observed at the grain boundaries of an Al casting, suggesting they were pushed during solidification; however, a small proportion were retained within the α-Al grains due to engulfment. Crystallographic analysis of the TiB2 with the surrounding α-Al showed that very few particles segregated to the grain boundaries showed any systematic relationship, while 70% of the engulfed particles display one of two orientation relationships, suggesting that the formation of a low-energy crystallographic relationship assists engulfment. [Copyright &y& Elsevier]

Niobium was found to be beneficial for alumina scale formation in newly developed creep-resistant austenitic stainless steels. Additions of both Ti and V degraded alumina scale formation, whereas alloys with individual additions of Ti or V were able to form protective alumina scales. The ability to form external alumina scales was lost in the lower Al- and Nb-containing alloys between 800 and 900°C. Compositions with the potential to form alumina at 900°C were identified. [Copyright &y& Elsevier]

Inspection of pre-polished surfaces of Mg–3Al–1Zn hot-rolled plate following 5% uniaxial compression revealed a distinctive heterogeneous deformation pattern. The pattern differed depending on the face examined. The greater share of the strain was born by regions characterized by grains considerably finer than the average. These regions displayed a favourable alignment for basal slip and were probably formed by shear banding during previous rolling. It is clear that local orientation softening leads to inhomogeneous deformation despite local grain size-hardening and twin activation. [Copyright &y& Elsevier]

Combined addition of strontium and boron led to a much greater decrease in the eutectic grain sizes in near-eutectic Al–Si alloys than that caused by addition of strontium alone. As expected, an increased cooling rate during solidification refines the eutectic grains. The mechanism of this refinement in the presence of strontium and boron is related to the combined effect of increased undercooling of the eutectic reaction and the effective number density of eutectic nuclei. [Copyright &y& Elsevier]

Extruded 15vol.% SiCp/Al–Cu–Mg composite was friction-stir-welded (FSW) and subjected to subsequent post-weld T4-treatment. The formation of Cu2FeAl7 phase with Fe resulting from steel tool wear was identified at or near the SiC particle interfaces by using transmission electron microscopy, high-resolution electron microscopy and differential scanning calorimetry. Two types of Cu2FeAl7 phases were observed: a single crystal phase and a polycrystalline nanostructured phase. No elemental iron was detected. The formation mechanism of the Cu2FeAl7 phase is discussed. [Copyright &y& Elsevier]

Abstract: The Al/p-Si Schottky diodes (33 dots) with the native interfacial insulator layer (SiO2) were fabricated on the same quarter Si wafer. The Schottky barrier height (SBH), ideality factor (n), interface state densities (N ss) and series resistance (R s) of these diodes have been calculated from their experimental forward bias current–voltage (I–V), reverse bias capacitance–voltage (C–V) and conductance–voltage (G/ω–V) measurements. Even though they are identically performed on the same quarter Si wafer, the calculated values of SBH have ranged from 0.680 to 0.736eV, and ideality factor n from 1.62 to 2.87, and interface state densities N ss from 0.395×1013 to 1.2×1013 eV−1 cm−2 and series resistance R s from 623 to 4900Ω. It was found that the values of barrier height Φ B obtained from C–V characteristics is larger than that of the value from I–V characteristics. The energy distribution of surface state density profiles for the selected six samples Al/p-Si Schottky diodes was determined from forward bias I–V characteristics by taking the bias dependence of the effective barrier height into account at room temperature. The experimental values of SBHs distributions obtained from the I–V and C −2–V characteristics have been fitted by a Gaussian function, and their mean values of SBHs have been calculated to be 0.708 and 0.810eV, respectively. Experimental results show that the interface states at a native insulator layer between metal and semiconductor play an important role in the value of the SBH, ideality factor, series resistance and the other main electrical parameters of Schottky diodes. [Copyright &y& Elsevier]

Abstract: The effects of applied transverse field on transition and compensation temperatures of the ternary alloy consisting of spins , , and are investigated by the use of a mean-field theory. The structure and the spin values of the model correspond to the Prussian blue analog of the type . We find that two or even three compensation points may be induced by a transverse field for the system with appropriate values of the parameters in the model Hamiltonian. In particular, the influence of a transverse field on the compensation point in the ground state is examined. [Copyright &y& Elsevier]

Abstract: We conducted nanoindentation to explore the hardness and elastic properties of silica stishovite, synthesized at high pressure and quenched to ambient conditions. A total of 10 crystallographic orientations were examined on selected grains with a maximum load of 4 or 20mN. We observed discontinuity in the load–displacement curve (pop-in) for the and grains subjected to a maximum load of 20mN. The single-crystal hardness at high plastic deformation is quasi-isotropic with an average of , similar to the polycrystalline hardness reported earlier; the theoretical hardness determined from the experiments is about . These two hardnesses suggest that stishovite is one of the hardest oxides. The measured indentation moduli are close to the predictions at low load (minor plasticity) but are considerably lower at high load (high plasticity). Both indentation hardness and modulus decrease with increasing plasticity. Our results underscore the necessity of considering the degree of plastic deformation when interpreting hardness and elastic moduli from indentation experiments. [Copyright &y& Elsevier]

Abstract: Electrical measurements have been performed on spin-coated azo-calix[4]arene derivative on pre-cleaned indium thin oxide (ITO) substrates using current versus voltage, capacitance versus voltage and impedance spectroscopy measurements. The nature of trap states in single layer ITO/azo-calix[4]arene derivative/Al organic diodes has also been investigated. The energy band gap of the thin film containing calixarene derivative has been measured by UV–Vis absorption spectroscopy and is about 2.77eV. The current–voltage characteristics have shown ohmic behavior at low voltages. At high applied bias the I–V characteristics can be successfully modeled by space-charge limited current (SCLC) theory. The impedance dependence of bias and frequency is discussed in terms of the presence of a depletion layer in the bulk. The device is accurately modeled, in a range of frequency between 100Hz and 1MHz, as a single parallel resistor and capacitor network placed in series with a resistance. Their values deduced from fitting experimental data to the model have given a dielectric relaxation time in the ms range and an exponential trap distribution. [Copyright &y& Elsevier]

Abstract: A rheological phase reaction method was developed to synthesize the nanocrystalline lanthanum-substituted lithium–nickel ferrites, Li0.25Ni0.5La x Fe2.25− x O4 (x=0.00, 0.025, 0.05, 0.075, 0.10). The structure, morphology, and magnetic properties of the as-prepared Li0.25Ni0.5La x Fe2.25− x O4 ferrites were characterized by powder X-ray diffractometer (XRD), scanning electron microscope (SEM), and vibrating sample magnetometer (VSM). It was shown that Li0.25Ni0.5La x Fe2.25− x O4 ferrites exhibited the single-phase spinel structure. The lattice parameters increased with increasing the La content, whereas the crystallite sizes decreased. The magnetic properties of Li0.25Ni0.5La x Fe2.25− x O4 ferrites were strongly affected by the La content. The saturation magnetization decreased, while coercivity increased with increasing the La content. [Copyright &y& Elsevier]

Abstract: We have studied the crystalline electric field (CEF) effect of the Ho1− x Dy x Ni2B2C system using the anisotropy and the temperature dependence of magnetic susceptibilities with magnetic field H perpendicular or parallel to c-axis, and estimated the magnetic exchange interaction constant of rare-earth ions perpendicular to the c-axis. The crystalline electric field parameter , the first Steven parameter and the most dominant term in this system, are determined from the and anisotropic Weiss temperatures and then show a broad minimum around x≈0.3, where superconducting transition temperature, T C, and Néel temperature, T N, are similar. [Copyright &y& Elsevier]

Abstract: The two-dimensional electron gas (2DEG) transport properties of two-step growth undoped Al0.25Ga0.75N/GaN heterostructures with semi-insulating buffer, grown by MOCVD, were investigated in a temperature range of 20–350K. Using the quantitative mobility spectrum analysis (QMSA) method, it was shown that significant parallel conduction does not occur in worked structures. In-plain growth axis strains are calculated using the total polarization-induced charge density taken as the sheet carrier density measured from the Hall effect. It was found that the calculated strain values are in good agreement with those reported. Influences of the two-step growth parameters such as growth ramp time, the annealing temperature of the GaN nucleation layer on the mobility, and density of the 2DEG are also discussed. [Copyright &y& Elsevier]

Abstract: Fe-doped ZnO nanorods were prepared using an in situ low-temperature hydrothermal synthesis. Fe-doped ZnO nanorods synthesized in the solution containing 30mM of (CH3CO2)2Fe exhibited a 40% increased I UV/I DLE ratio compared to undoped ZnO nanorods. Oxygen deficiencies were significantly reduced with Fe doping in ZnO nanorods, and Fe was incorporated in ZnO nanostructure in a Fe3+-like state. It is suggested that the addition of Fe3+ into a ZnO nanostructure disturbs the recombination of electrons and holes by bonding with electrons in singly ionized oxygen vacancies. Consequently, green emission is reduced and the optical properties of ZnO nanorods are improved. [Copyright &y& Elsevier]

Abstract: The expressions of the light intensity (Poynting vector) and the transmission coefficient related to counterposition phenomenon are deduced. The counterposition phenomenon in the uniaxial crystal makes no difference to ordinary refraction in terms of energy transport efficiency though it carries the light energy in a different way. [Copyright &y& Elsevier]

Abstract: In this paper we present a study of the energy gaps, dielectric constants and their composition dependence in zinc-blende Cd1− x Zn x Te over the entire composition range (x from 0 to 1) at room temperature using pseudopotential formalism under a modified virtual crystal approximation which takes into account the effect of compositional disorder. It is showed that the theoretical model must include disorder effects in order to get a meaningful agreement with experiment. The theoretical expression which describes the compositional dependence of the fundamental energy gap is in good agreement with that observed by Tobin et al. [J. Electron. Mater. 24 (1995) 697]. [Copyright &y& Elsevier]

Abstract: We have investigated the effect of the partial substitution of Ca by Sm in the Bi-2223 superconducting samples prepared by standard solid-state reaction method. Our investigations consisted of DC electrical resistivity, AC susceptibility, X-ray diffraction (XRD) and scanning electron microscopy (SEM) measurements. We measured the critical transition temperatures, activation energies and irreversibility lines from the resistivity versus temperature curves under DC magnetic fields in the range of 0 and 0.6T. The superconducting transition temperature, , and activation energy, , were found to decrease with increasing Sm concentration and with increasing applied magnetic field. Increasing the Sm content shifted the irreversibility temperature to lower values. The AC susceptibility measurements were carried out at 80A/m field strength and frequency. XRD patterns and SEM micrographs are given to provide information about Bi-2223 and Bi-2212 phases and their grain size. The possible reasons for the observed degradation in microstructural and superconducting properties due to Sm substitution were discussed. [Copyright &y& Elsevier]

Abstract: The spin structure in a magnetic dot is studied as a function of the exchange coupling strength and dot size within the semiclassical approximation on a discrete lattice. As the exchange coupling is decreased or the size is increased, the ground state undergoes a phase change from a homogeneous single-domain ferromagnet (HSDF) to a spin vortex. The line separating these two phases has been calculated numerically for small system sizes. The dipolar interaction has been fully included in our calculations. Magnon frequencies in such a dot have also been calculated in both phases by the linearized equation of motion method. These results have also been reproduced from the Fourier transform of the spin autocorrelation function. From the magnon density of states (DOS), it is possible to identify the magnetic phase of the dot, as well as to compute their finite temperature magnetization or vorticity. Furthermore, the magnon modes have been characterized for both the homogeneous ferromagnetic and the vortex phase, and the magnon instability mechanism leading to the vortex-HSDF transition has also been identified. [Copyright &y& Elsevier]

Abstract: We have studied a left–right symmetric model with mirror fermions based on a grand unified model in order to account for the muon anomaly. The Higgs sector of the model contains two Higgs doublets and the hierarchy condition can be achieved by using two additional Higgs singlets, one even and other odd under -parity. We show that there is a wide range of values for the mass parameters of the model that is consistent with the lepton anomalies. Radiative correction to the mass of the ordinary fermions are considered to be small. [Copyright &y& Elsevier]

Abstract: We determine an approximate expression for the contribution to the kernel of the BFKL equation, which includes all collinear and anticollinear singular contributions. This is derived using recent results on the relation between the GLAP and BFKL kernels (including running-coupling effects to all orders) and on small-x factorization schemes. We present the result in various schemes, relevant both for applications to the BFKL equation and to small-x evolution of parton distributions. [Copyright &y& Elsevier]

Abstract: Recursion relations are derived in the sense of Berends–Giele for the multi-photon processes of noncommutative QED. The relations concern purely photonic processes as well as the processes with two fermions involved, both for arbitrary number of photons at tree level. It is shown that despite of the dependence of noncommutative vertices on momentum, in contrast to momentum-independent color factors of QCD, the recursion relation method can be employed for multi-photon processes of noncommutative QED. [Copyright &y& Elsevier]

Abstract: We assume that the Pauli exclusion principle is violated for neutrinos, and thus, neutrinos obey at least partly the Bose–Einstein statistics. The parameter is introduced that characterizes the bosonic (symmetric) fraction of the neutrino wave function. Consequences of the violation of the exclusion principle for the two-neutrino double beta decays (-decays) are considered. This violation strongly changes the rates of the decays and modifies the energy and angular distributions of the emitted electrons. Pure bosonic neutrinos are excluded by the present data. In the case of partly bosonic (or mixed-statistics) neutrinos the analysis of the existing data allows to put the conservative upper bound . The sensitivity of future measurements of the -decay to is evaluated. [Copyright &y& Elsevier]

Abstract: We systematically analyze the correlations between the various leptonic and hadronic flavor violating processes arising in SUSY Grand Unified Theories. Using the GUT-symmetric relations between the soft SUSY breaking parameters, we assess the impact of hadronic and leptonic flavor observables on the SUSY sources of flavor violation. [Copyright &y& Elsevier]

Abstract: We consider the time-dependence of the Higgs vacuum expectation value (vev) given by the dynamics of the Standard Model and study the non-adiabatic production of both bosons and fermions, which is intrinsically non-perturbative. In the Hartree approximation, we analyze the general expressions that describe the dissipative dynamics due to the back-reaction of the produced particles. In particular, we solve numerically some relevant cases for the Standard Model phenomenology in the regime of relatively small oscillations of the Higgs vev. [Copyright &y& Elsevier]

Abstract: We present ten phenomenologically viable neutrino mass textures, which are approximately symmetric: two for the normal mass hierarchy, three for the inverted mass hierarchy, and five for the quasi-degenerate mass pattern. Each texture falls into two categories characterized by either (referred to as (C1)), or (referred to as (C2)) in the symmetric limit, where and , respectively, stand for the and mixing angles. Our textures that depend on the signs of neutrino masses as well as on (C1) and (C2) are so constructed to satisfy general relations, which ensure that and , where and are neutrino mass differences squared, respectively, for solar and atmospheric neutrinos. Three textures are found to provide . [Copyright &y& Elsevier]

Abstract: In this second paper, we prove a necessity theorem about the topological origin of phase transitions. We consider physical systems described by smooth microscopic interaction potentials , among N degrees of freedom, and the associated family of configuration space submanifolds , with . On the basis of an analytic relationship between a suitably weighed sum of the Morse indexes of the manifolds and thermodynamic entropy, the theorem states that any possible unbound growth with N of one of the following derivatives of the configurational entropy , that is of , for , can be entailed only by the weighed sum of Morse indexes. Since the unbound growth with N of one of these derivatives corresponds to the occurrence of a first- or of a second-order phase transition, and since the variation of the Morse indexes of a manifold is in one-to-one correspondence with a change of its topology, the Main Theorem of the present paper states that a phase transition necessarily stems from a topological transition in configuration space. The proof of the theorem given in the present paper cannot be done without Main Theorem of paper I. [Copyright &y& Elsevier]

Abstract: A Toda equation is specified by a choice of a Lie group and a -gradation of its Lie algebra. The Toda equations associated with loop groups of complex classical Lie groups, whose Lie algebras are endowed with integrable -gradations with finite dimensional grading subspaces, are described in an explicit form. [Copyright &y& Elsevier]

Abstract: By using the super Yangian symmetry of the supersymmetric Haldane–Shastry spin chain, we show that the partition function of this model satisfies a duality relation under the exchange of bosonic and fermionic spin degrees of freedom. As a byproduct of this study of the duality relation, we find a novel combinatorial formula for the super Schur polynomials associated with some irreducible representations of the Yangian algebra. Finally, we reveal an intimate connection between the global symmetry of a spin chain and the boson–fermion duality relation. [Copyright &y& Elsevier]

Abstract: In this first paper, we demonstrate a theorem that establishes a first step toward proving a necessary topological condition for the occurrence of first- or second-order phase transitions: we prove that the topology of certain submanifolds of configuration space must necessarily change at the phase transition point. The theorem applies to smooth, finite-range and confining potentials V bounded below, describing systems confined in finite regions of space with continuously varying coordinates. The relevant configuration space submanifolds are both the level sets of the potential function and the configuration space submanifolds enclosed by the defined by , which are labeled by the potential energy value v, and where N is the number of degrees of freedom. The proof of the theorem proceeds by showing that, under the assumption of diffeomorphicity of the equipotential hypersurfaces , as well as of the , in an arbitrary interval of values for , the Helmholtz free energy is uniformly convergent in N to its thermodynamic limit, at least within the class of twice differentiable functions, in the corresponding interval of temperature. This preliminary theorem is essential to prove another theorem—in paper II—which makes a stronger statement about the relevance of topology for phase transitions. [Copyright &y& Elsevier]

Abstract: Recently an explicit resolution of the Calabi–Yau cone over the inhomogeneous five-dimensional Einstein–Sasaki space was obtained. It was constructed by specialising the parameters in the BPS limit of recently-discovered Kerr–NUT–AdS metrics in higher dimensions. We study the occurrence of such non-singular resolutions of Calabi–Yau cones in a more general context. Although no further six-dimensional examples arise as resolutions of cones over the Einstein–Sasaki spaces, we find general classes of non-singular cohomogeneity-2 resolutions of higher-dimensional Einstein–Sasaki spaces. The topologies of the resolved spaces are of the form of an bundle over a base manifold that is itself an bundle over an Einstein–Kähler manifold. [Copyright &y& Elsevier]

Abstract: We study little Higgs models based on a global symmetry and with two scales (the two vacuum expectation values ) substantially different. We show that all the extra vector boson fields present in these models may be much heavier than the vectorlike T quark necessary to cancel top-quark quadratic corrections. In this case the models become an extension of the Standard Model with a light T quark and a scalar Higgs field with a large singlet component. We obtain that the Yukawa and the gauge couplings of the Higgs are smaller than in the standard model, a fact that may reduce significantly the Higgs production rate through glu–glu and WW fusion. The T quark decay into Higgs boson becomes then the dominant Higgs production channel in hadron colliders. [Copyright &y& Elsevier]

Abstract: Firstly, we generalize a semi-classical limit of open strings on D-branes in group manifolds. The limit gives rise to rigid open strings, whose dynamics can efficiently be described in terms of a matrix algebra. Alternatively, the dynamics is coded in group theory coefficients whose properties are translated in a diagrammatical language. In the case of compact groups, it is a simplified version of rational boundary conformal field theories, while for non-compact groups, the construction gives rise to new associative products. Secondly, we argue that the intuitive formalism that we provide for the semi-classical limit, extends to the case of quantum groups. The associative product we construct in this way is directly related to the boundary vertex operator algebra of open strings on symmetry preserving branes in WZW models, and generalizations thereof, e.g. to non-compact groups. We treat the groups and explicitly. We also discuss the precise relation of the semi-classical open string dynamics to Berezin quantization and to star product theory. [Copyright &y& Elsevier]

Abstract: Lattice power-counting is extended to QCD with staggered fermions. As preparation, the difficulties encountered by Reisz''s original formulation of the lattice power-counting theorem are illustrated. One of the assumptions that is used in his proof does not hold for staggered fermions, as was pointed out long ago by Lüscher. Finally, I generalize the power-counting theorem, and the methods of Reisz''s proof, such that the difficulties posed by staggered fermions are overcome. [Copyright &y& Elsevier]

Abstract: It is a commonly held belief that a consistent dimensional reduction ansatz can be equally well substituted into either the higher-dimensional equations of motion or the higher-dimensional action, and that the resulting lower-dimensional theories will be the same. This is certainly true for Kaluza–Klein circle reductions and for DeWitt group-manifold reductions, where group-invariance arguments guarantee the equivalence. In this paper we address the question in the case of the non-trivial consistent Pauli coset reductions, such as the and reductions of eleven-dimensional supergravity. These always work at the level of the equations of motion. In some cases the reduction ansatz can only be given at the level of field strengths, rather than the gauge potentials which are the fundamental fields in the action, and so in such cases there is certainly no question of being able to substitute instead into the action. By examining explicit examples, we show that even in cases where the ansatz can be given for the fundamental fields appearing in an action, substituting it into the higher-dimensional action may not give the correct lower-dimensional theory. This highlights the fact that much remains to be understood about the way in which Pauli reductions work. [Copyright &y& Elsevier]

Abstract: We derive for deep-inelastic neutrino(ν)–proton(P) scattering in the combination the perturbative QCD corrections to three loops for the charged current structure functions , and . In leading twist approximation we calculate the first five odd-integer Mellin moments in the case of and and the first five even-integer moments in the case of . As a new result we obtain the coefficient functions to while the corresponding anomalous dimensions agree with known results in the literature. [Copyright &y& Elsevier]

Abstract: Inflation allows the problem of the arrow of time to be understood as a question about the structure of spacetime: why was the intrinsic curvature of the earliest spatial sections so much better behaved than it might have been? This is really just the complement of a more familiar problem: what mechanism prevents the extrinsic curvature of the earliest spatial sections from diverging, as classical general relativity suggests? We argue that the stringy version of “creation from nothing”, sketched by Ooguri, Vafa, and Verlinde, solves both of these problems at once. The argument, while very simple, hinges on some of the deepest theorems in global differential geometry. These results imply that when a spatially toral spacetime is created from nothing, the earliest spatial sections are forced to be [quasi-classically] exactly locally isotropic. This local isotropy, in turn, forces the inflaton into its minimal-entropy state. The theory explains why the arrow does not reverse in black holes or in a cosmic contraction, if any. [Copyright &y& Elsevier]

Abstract: Non-perturbative effects are studied for type I strings on the orbifold with Chan–Paton symmetry broken by Wilson lines. Generalizing previous analyses that have focussed on (bi)fundamentals, it is argued that (anti)symmetric representations of the resulting gauge group play a decisive role in generating an ADS-like superpotential in this and related cases. Non-perturbative corrections in the closed string moduli are only allowed if properly dressed with open string fields charged under the anomalous of the orbifold. A general discussion of instanton effects in SYM and string theories is given. Non-perturbative superpotentials induced by both ED5''s and ED1''s are analyzed. The superpotential generated by closed string fluxes, viz. Scherk–Schwarz shifts (torsion), R–R 3-form flux as well as non-geometric fluxes is derived. Some preliminary comments on the compatibility of the two kinds of superpotentials and the issue of moduli stabilization are presented. [Copyright &y& Elsevier]

Abstract: The final state interactions (FSI) model in which soft rescattering of low mass intermediate states dominates is suggested. It explains why the strong interaction phases are large in the channel and are considerably smaller in the one. Direct CP asymmetries of decays which are determined by FSI phases are considered as well. [Copyright &y& Elsevier]

Abstract: We consider the bosonic sector of the maximally supersymmetric SYM model and show that anomalous dimension of the twist-3 single-trace composite operators built of scalar fields, recently calculated up to the four-loop order, can be generated by a compact reciprocity respecting evolution kernel. [Copyright &y& Elsevier]

Abstract: We study the neutral minima of two-Higgs doublet models, showing that these potentials can have at least two such minima with different depths. We analyse the phenomenology of these minima for the several types of two-Higgs doublet potentials, where CP is explicitly broken, spontaneously broken or preserved. We discover that it is possible to have a neutral minimum in these potentials where the masses of the known particles have their standard values, with another deeper minimum where those same particles acquire different masses. [Copyright &y& Elsevier]

Abstract: Quadrupole deformation parameters, , have been deduced for 36,38,40Si from measured inelastic proton-scattering cross sections. Due to the strong subshell gap, low-lying quadrupole collectivity in these nuclei is attributed to the excitation of valence neutrons. Enhanced collectivity at indicates a reduced shell gap at large neutron excess in this chain of isotopes. Data are compared to large-scale shell-model calculations and prior Coulomb excitation measurements on 36,38Si. [Copyright &y& Elsevier]