September 2009 arXiv papers — page 10

Pierre Comon, Giorgio Ottaviani

We determine the rank of a general real binary form of degree d=4 and d=5. In the case d=5, the possible values of the rank of such general forms are 3,4,5. The existence of three typical ranks was unexpected. We prove that a real binary form of degree d with d real roots has rank d.

Miao Zhang, H. Y. Jia, J. S. Huang, L. F. Wei

An electron floating on the liquid Helium is proposed to be trapped (by a micro-electrode set below the liquid Helium) in a high finesse cavity. Two lowest levels of the vertical motion of the electron acts as a two-level "atom", which could resonantly interact with the THz cavity. In the Lamb-Dicke regime, wherein the electron's in-plane activit

Najib Mahdou, Mohammed Tamekkante

In this paper, we compare the Gorenstein homological dimension of a ring $R$ and of its trivial ring extension by an module $E$.

V. L. Grigoryan, A. Matos Abiague, S. M. Badalyan

We study the spin edge states, induced by the combined effect of spin-orbit interaction (SOI) and hard-wall confining potential, in a two-dimensional electron system, exposed to a perpendicular magnetic field. We find an exact solution of the problem and show that the spin resolved edge states are separated in space. The SOI generated rearrangement of the sp

Y. Robiah, S. Siti Rahayu, M. Mohd Zaki, S. Shahrin

Malware is a type of malicious program that replicate from host machine and propagate through network. It has been considered as one type of computer attack and intrusion that can do a variety of malicious activity on a computer. This paper addresses the current trend of malware detection techniques and identifies the significant criteria in each technique t

S. Rathi, K. Thanuskodi

Mobile IPv6 will be an integral part of the next generation Internet protocol. The importance of mobility in the Internet gets keep on increasing. Current specification of Mobile IPv6 does not provide proper support for reliability in the mobile network and there are other problems associated with it. In this paper, we propose Virtual Private Network (VPN) b

Paul Ramsden

Let G be a locally compact group, and let 1 < p < \infty. In this paper we investigate the injectivity of the left L^1(G)-module L^p(G). We define a family of amenability type conditions called (p,q)-amenability, for any 1 <= p <= q. For a general locally compact group G we show if L^p(G) is injective, then G must be (p,p)-amenable. For a discrete group G we

Won Sang Cho, Kiwoon Choi, Yeong Gyun Kim, Chan Beom Park

We discuss the M_T2-kink method to determine the masses of both the dark matter WIMP and its mother particle produced at the LHC. We then introduce a new kinematic variable, the M_T2-Assisted-On-Shell (MAOS) momentum, that provides a systematic approximation to the invisible particle momenta in hadron collider events producing a pair of invisible particles,

N. N. Bogolubov, A. K. Prykarpatsky

The work is devoted to studying some new classical electrodynamics models of interacting charged point particles and the aspects of the quantization via the Dirac procedure related to them. Based on the vacuum field theory no-geometry approach developed in [6,7,9], the Lagrangian and Hamiltonian reformulations of some alternative classical electrodynamics mo

Shao-Ming Fei, Ming-Jing Zhao, Kai Chen, Zhi-Xi Wang

We present a way of experimentally determining the concurrence in terms of the expectation values of local observables for arbitrary multipartite pure states. In stead of the joint measurements on two copies of a state in the experiment for two-qubit systems [S. P. Walborn et al. Nature (London)440, 20(2006)], we only need one copy of the state in every meas

Sandipan Sengupta, Romesh K. Kaul

A canonical formulation of the N=1 supergravity theory containing the topological Nieh-Yan term in its Lagrangian density is developed. The constraints are analysed without choosing any gauge. In the time gauge, the theory is shown to be described in terms of real SU(2) variables.

Alan L. Carey, Bai-Ling Wang

In this paper, we establish the Riemann-Roch theorem in twisted K-theory extending our earlier results. As an application, we prove a twisted index formula and show that D-brane charges in Type I and Type II string theory are classified by twisted KO-theory and twisted K-theory respectively in the presence of B-fields as proposed by Witten.

Noam Soker

I argue that the Doppler shift asymmetries observed in some young stellar object (YSO) result from the interaction of the jets with the circumstellar gas, rather than from jets&#39; rotation. The jets do rotate, but at a velocity much below claimed values. During the meeting I carefully examined new claims, and found problems with the claimed jets&#39; rotat

K. A. Penson, P. Blasiak, G. H. E. Duchamp, A. Horzela

We construct explicit solutions of a number of Stieltjes moment problems based on moments of the form $ρ_{1}^{(r)}(n)=(2rn)!$ and $ρ_{2}^{(r)}(n)=[(rn)!]^{2}$, $r=1,2,...$, $n=0,1,2,...$, \textit{i.e.} we find functions $W^{(r)}_{1,2}(x)>0$ satisfying $\int_{0}^{\infty}x^{n}W^{(r)}_{1,2}(x)dx = ρ_{1,2}^{(r)}(n)$. It is shown using criteria for uniqueness and

Paolo Bellingeri, Cattabriga Alessia

Let $\H_g$ be a genus $g$ handlebody and $\MCG_{2n}(\T_g)$ be the $2n$-punctured mapping class group of $\T_g=\partial\H_g$. In this paper we study two particular subgroups of $\MCG_{2n}(\T_g)$ which generalize Hilden groups. As well as Hilden groups are related to plate closures of braids, these generalizations are related to Heegaard splittings of manifold

Alexander Kleshchev

This is an expository article. We survey some fundamental trends in representation theory of symmetric groups and related objects which became apparent in the last fifteen years. The emphasis is on connections with Lie theory via categorification. We present results on branching rules and crystal graphs, decomposition numbers and canonical bases, graded repr

Wei-Min Gu, Li Xue, Tong Liu, Ju-Fu Lu

We revisit the vertical structure of black hole accretion disks in spherical coordinates. By comparing the advective cooling with the viscous heating, we show that advection-dominated disks are geometrically thick, i.e., with the half-opening angle > 2π/5, rather than slim as supposed previously in the literature.

Ajay Gupta, Dileep Kumar, Vaishali Phatak

Nanoscale diffusion at the interfaces in multilayers plays a vital role in controlling their physical properties for a variety of applications. In the present work depth-dependent interdiffusion in a Si/Fe/Si trilayer has been studied with sub-nanometer depth resolution, using x ray standing waves. High depth-selectivity of the present technique allows one t

B. J. Wundt, U. D. Jentschura

We calculate the relativistic corrections of relative order (Z alpha)^2$ to the two-photon decay rate of higher excited S and D states in ionic atomic systems, and we also evaluate the leading radiative corrections of relative order alpha (Z alpha)^2 ln[(Z alpha)^(-2)]. We thus complete the theory of the two-photon decay rates up to relative order alpha^3 ln

Yan-Jun Chu, Fang Huang, Zhu-Jun Zheng

Analogue to commutants in the theory of associative algebras, one can construct a new subalgebra of vertex algebra known as a vertex algebra commutant. In this paper, for the adjoint representation $V$ of Lie algebra $sl(2,\C)$, we describe a commutant of $βγ$- System $S(V)$ by giving its generators, moreover, we get a new Howe pair of vertex algebras.

Luis Daniel Abreu

Motivated by potential applications in multiplexing and by recent results on Gabor analysis with Hermite windows due to Gröchenig and Lyubarskii, we investigate vector-valued wavelet transforms and vector-valued wavelet frames, which constitute special cases of super-wavelets, with a particular attention to the case when the analyzing wavelet vector is relat

Saverio E. Spagnolie, Eric Lauga

Motile eukaryotic cells propel themselves in viscous fluids by passing waves of bending deformation down their flagella. An infinitely long flagellum achieves a hydrodynamically optimal low-Reynolds number locomotion when the angle between its local tangent and the swimming direction remains constant along its length. Optimal flagella therefore adopt the sha

Thomas Church, Benson Farb

Consider the kernel Mag_g of the Magnus representation of the Torelli group and the kernel Bur_n of the Burau representation of the braid group. We prove that for g >= 2 and for n >= 6 the groups Mag_g and Bur_n have infinite rank first homology. As a consequence we conclude that neither group has any finite generating set. The method of proof in each case c

Jose L. Martinez-Morales

In absence of explicit solutions of the perturbation equation of a static symmetrical homogeneous space-time, the best we can do is to construct a {\it quasi-}transformation. In this framework, we solve the perturbation equation with initial data and a number of results are derived. Far from the horizon of a black hole of even space dimension $N$, a mass-les

Karyn Le Hur

Spin-boson models are essentially useful in the understanding of quantum optics, nuclear physics, quantum dissipation, and quantum computation. We discuss quantum phase transitions in various spin-boson Hamiltonians, compare, and contrast them. We summarize the theoretical concepts and results, open questions and implementations of those ideas in cold atomic

D. Hsieh, Y. Xia, D. Qian, L. Wray

We show that the strongly spin-orbit coupled materials Bi2Te3 and Sb2Te3 (first non-Bi topological insulator) and their derivatives belong to the Z2 (Time-Reversal-Protected, elastic backscattering suppressed) topological-insulator class. Using a combination of first-principles theoretical calculations and photoemission spectroscopy, we directly show that Bi

Hisayuki Hara, Tomonari Sei, Akimichi Takemura

For statistical analysis of multiway contingency tables we propose modeling interaction terms in each maximal compact component of a hierarchical model. By this approach we can search for parsimonious models with smaller degrees of freedom than the usual hierarchical model, while preserving conditional independence structures in the hierarchical model. We di

Y. E. Lyubarsky

The acceleration of relativistic jets from the Poynting to the matter dominated stage is considered. The are generally two collimation regimes, which we call equilibrium and non-equilibrium, correspondingly. In the first regime, the jet is efficiently accelerated till the equipartition between the kinetic and electro-magnetic energy. We show that after the e

Zhi Jiang

Let $f: X\to Y$ be a surjective morphism of smooth $n$-dimensional projective varieties, with $Y$ of maximal Albanese dimension. Hacon and Pardini studied the structure of $f$ assuming $P_m(X)=P_m(Y)$ for some $m\geq 2$. We extend their result by showing that, under the above assumtions, $f$ is birationally equivalent to a quotient by a finite abelian group.

D0 Collaboration, V. Abazov

We present a direct measurement of the width of the W boson using the shape of the transverse mass distribution of W->enu candidates selected in 1 fb-1 of data collected with the D0 detector at the Fermilab Tevatron collider in ppbar collisions at sqrt{s}=1.96 TeV. We use the same methods and data sample that were used for our recently published W boson mass

David J. Masiello, George C. Schatz

A many-body Green&#39;s function approach to the microscopic theory of plasmon-enhanced spectroscopy is presented within the context of localized surface-plasmon resonance spectroscopy and applied to investigate the coupling between quantum-molecular and classical-plasmonic resonances in monolayer-coated silver nanoparticles. Electronic propagators or Green&

Cristian D. Gonzalez-Aviles

Let F be a global field and let S denote a nonempty finite set of primes of F containing the set S&#39; of archimedean primes of F. In this paper we study the Neron S-class group C_{A,F,S} of an abelian variety A defined over F. In the well-known analogy that exists between the Birch and Swinnerton-Dyer conjecture for A over F and Dirichlet&#39;s analytic cl

J. Viana-Gomes, Vitor M. Pereira, N. M. R. Peres

We study the magnetization of square and hexagonal graphene dots. It is shown that two classes of hexagonal dots have a second order phase transition at a critical Hubbard energy $U$, whoose value is similar to the one in bulk graphene, albeit the dots do not have a density of states proportional to the absolute value of the energy, relatively to the Dirac p

Peter Hinow

Motivated by a problem arising from pharmaceutical science [B. Baeumer et al., Discr. Contin. Dyn. Sys. B 12], we study random walks on the contact graph of a bidisperse random sphere packing. For a random walk on the unweighted graph that terminates in a specified target set, we compare the number of steps and the total euclidean length of the walk. We find

Cecilia E. Gerber

I report on the observation of electroweak production of single top quarks in proton anti-proton collisions at a center of mass energy of 1.96 TeV using 2.3 inverse-fb of data collected with the D0 detector at the Fermilab Tevatron Collider. Using events containing an isolated electron or muon, missing transverse energy, two, three or four jets, with one or

R. Falewicz, P. Rudawy, M. Siarkowski

Standard model of solar flares comprises a bulk expansion and rise of abruptly heated plasma (the chromospheric evaporation). Emission from plasma ascending along loops rooted on the visible solar disk should be often dominated, at least temporally, by a blue-shifted emission. However, there is only a very limited number of published observations of solar fl

Andreas Hackl, Matthias Vojta

We analyze the thermoelectric response in layered metals with spontaneously broken rotation symmetry. We identify the anisotropy of the quasiparticle Nernst signal as an extremely sensitive probe of Fermi surface distortions characteristic of the ordered state. This is due to a subtle interplay of different transport anisotropies which become additionally en

Manoel Moraes, Marcos Diaz

The HR Del nova remnant was observed with the IFU-GMOS at Gemini North. The spatially resolved spectral data cube was used in the kinematic, morphological and abundance analysis of the ejecta. The line maps show a very clumpy shell with two main symmetric structures. The first one is the outer part of the shell seen in H-alpha, that forms two rings projected

Haydee Herrera, Rafael Herrera

We prove the vanishing of higher A-hat-genera, in the sense of Browder and Hsiang, on smooth manifolds with effective circle actions and with finite second and fourth homotopy groups

R. Flint, H. -T. Yi, P. Chandra, S. -W. Cheong

Ca_3Co_{2-x}Mn_xO_6 (x ~ 0.96) is a multiferroic with spin-chains of alternating Co(2+) and Mn(4+) ions. The spin state of Co(2+) remains unresolved, due to a discrepancy between high temperature X-ray absorption (S=3/2) and low temperature neutron (S=1/2) measurements. Using a combination of magnetic modeling and crystal-field analysis, we show that the exi

Maqbool Ahmed, David Rideout

A large class of the dynamical laws for causal sets described by a classical process of sequential growth yield a cyclic universe, whose cycles of expansion and contraction are punctuated by single `origin elements&#39; of the causal set. We present evidence that the effective dynamics of the immediate future of one of these origin elements, within the conte

M. Saffman, T. G. Walker, K. Molmer

Rydberg atoms with principal quantum number n >> 1 have exaggerated atomic properties including dipole-dipole interactions that scale as n^4 and radiative lifetimes that scale as n^3. It was proposed a decade ago to take advantage of these properties to implement quantum gates between neutral atom qubits. The availability of a strong, long-range interaction

Christine Bachoc

These lecture notes where presented as a course of the CIMPA summer school in Manila, July 20-30, 2009, Semidefinite programming in algebraic combinatorics. This version is an update June 2010.

Edward Farhi, Jeffrey Goldstone, David Gosset, Sam Gutmann

We construct a set of instances of 3SAT which are not solved efficiently using the simplest quantum adiabatic algorithm. These instances are obtained by picking random clauses all consistent with two disparate planted solutions and then penalizing one of them with a single additional clause. We argue that by randomly modifying the beginning Hamiltonian, one

Akbar Ghasemi, Abolfazl Seyed Motahari, Amir Keyvan Khandani

We consider the $K$-user Multiple Input Multiple Output (MIMO) Gaussian interference channel with $M$ antennas at each transmitter and $N$ antennas at each receiver. It is assumed that channel coefficients are constant and are available at all transmitters and at all receivers. The main objective of this paper is to characterize the Degrees of Freedom (DoF)

Jacek Jakubowski, Maciej Wisniewolski

In this paper we investigate general linear stochastic volatility models with correlated Brownian noises. In such models the asset price satisfies a linear SDE with coefficient of linearity being the volatility process. This class contains among others Black-Scholes model, a log-normal stochastic volatility model and Heston stochastic volatility model. For a

Qing Xu, Sabre Kais, Maxim Naumov, Ahmed Sameh

Using the Trace Minimization Algorithm, we carried out an exact calculation of entanglement in a 19-site two-dimensional transverse Ising model. This model consists of a set of localized spin-1/2 particles in a two dimensional triangular lattice coupled through exchange interaction J and subject to an external magnetic field of strength h. We demonstrate, fo

Ron-Chou Hsieh, Hsiang-nan Li

We include effects of nonlocal quark condensates into QCD sum rules (QSR) via the K$\ddot{\mathrm{a}}$ll$\acute{\mathrm{e}}$n-Lehmann representation for a dressed fermion propagator, in which a negative spectral density function manifests their nonperturbative nature. Applying our formalism to the pion form factor as an example, QSR results are in good agree

Kazuki Koshino, Satoshi Ishizaka, Yasunobu Nakamura

We theoretically present a method to realize a deterministic photon-photon (SWAP)^{1/2} gate using a three-level lambda system interacting with single photons in reflection geometry. The lambda system is used completely passively as a temporary memory for a photonic qubit; the initial state of the lambda system may be arbitrary, and active control by auxilia

Zhaohu Nie

The Law of Vector Fields is a term coined by Gottlieb for a relative Poincaré-Hopf theorem. It was first proved by Morse and expresses the Euler characteristic of a manifold with boundary in terms of the indices of a generic vector field and the inner part of its tangential projection on the boundary. We give two differential-geometric proofs of this topolog

Jason D. Hartline, Brendan Lucier

The principal problem in algorithmic mechanism design is in merging the incentive constraints imposed by selfish behavior with the algorithmic constraints imposed by computational intractability. This field is motivated by the observation that the preeminent approach for designing incentive compatible mechanisms, namely that of Vickrey, Clarke, and Groves; a

Philipp P. Kronberg, Katherine J. Newton-McGee

Using a new, expanded compilation of extragalactic source Faraday rotation measures (RM) we investigate the broad underlying magnetic structure of the Galactic disk at latitudes $|b|$ $\lesssim 15^{\circ}$ over all longitudes $l$, where our total number of RM&#39;s in this low-latitude range of the Galactic sky is comparable to those in the combined Canadian

Jeffrey C. Y. Teo, C. L. Kane

We show that three dimensional superconductors, described within a Bogoliubov de Gennes framework can have zero energy bound states associated with pointlike topological defects. The Majorana fermions associated with these modes have non-Abelian exchange statistics, despite the fact that the braid group is trivial in three dimensions. This can occur because

Friedwardt Winterberg

Exact solutions of a magnetized plasma in a vorticity containing shear flow for constant temperature are presented. This is followed by the modification of these solutions by thermomagnetic currents in the presence of temperature gradients. It is shown that solutions which are unstable for a subsonic flow, are stable if the flow is supersonic. The results ar

L. A. Harland-Lang, V. A. Khoze, M. G. Ryskin, W. J. Stirling

Motivated by the recent experimental observation of exclusive chi_c events at the Tevatron, we revisit earlier studies of central exclusive scalar chi_c0 meson production, before generalising the existing formalism to include chi_c1 and chi_c2 mesons. Although chi_c0 production was previously assumed to be dominant, we find that the chi_c1 and chi_c2 rates f

Brendan Hassett, Yuri Tschinkel

We propose a general framework governing the intersection properties of extremal rays of irreducible holomorphic symplectic manifolds under the Beauville-Bogomolov form. Our main thesis is that extremal rays associated to Lagrangian projective subspaces control the behavior of the cone of curves. We explore implications of this philosophy for examples like H

Hisham Sati

The massless supermultiplet of eleven-dimensional supergravity can be generated from the decomposition of certain representation of the exceptional Lie group F4 into those of its maximal compact subgroup Spin(9). In an earlier paper, a dynamical Kaluza-Klein origin of this observation is proposed with internal space the Cayley plane, OP2, and topological asp

E. Tomasi-Gustafsson, M. Osipenko, E. A. Kuraev, Yu. Bystritsky

World data on the lepton-charge asymmetry in the elastic and inelastic lepton scattering off the proton and nuclei are compiled and discussed. After reviewing the published results, we compare the elastic data to a model calculation of the two-photon exchange mechanism. We show that the existing data do not provide any evidence for the two-photon contributio

Arvind Ayyer

We construct a direct natural bijection between descending plane partitions without any special part and permutations. The directness is in the sense that the bijection avoids any reference to nonintersecting lattice paths. The advantage of the bijection is that it provides an interpretation for the seemingly long list of conditions needed to define descendi

Xavier Cabre

We consider the class of semi-stable solutions to semilinear equations $-Δu=f(u)$ in a bounded smooth domain $Ω$ of $R^n$ (with $Ω$ convex in some results). This class includes all local minimizers, minimal, and extremal solutions. In dimensions $n \leq 4$, we establish an priori $L^\infty$ bound which holds for every positive semi-stable solution and every

Árpád Bényi, Diego Maldonado, Virginia Naibo, Rodolfo H. Torres

Bilinear pseudodifferential operators with symbols in the bilinear analog of all the Hörmander classes are considered and the possibility of a symbolic calculus for the transposes of the operators in such classes is investigated. Precise results about which classes are closed under transposition and can be characterized in terms of asymptotic expansions are

K. Narayan

We continue exploring free strings in the background of null Kasner-like cosmological singularities, following arXiv:0904.4532 [hep-th]. We study the free string Schrodinger wavefunctional along the lines of arXiv:0807.1517 [hep-th]. We find the wavefunctional to be nonsingular in the vicinity of singularities whose Kasner exponents satisfy certain relations

Ilias Diakonikolas, Rocco A. Servedio, Li-Yang Tan, Andrew Wan

We give a &#34;regularity lemma&#34; for degree-d polynomial threshold functions (PTFs) over the Boolean cube {-1,1}^n. This result shows that every degree-d PTF can be decomposed into a constant number of subfunctions such that almost all of the subfunctions are close to being regular PTFs. Here a &#34;regular PTF is a PTF sign(p(x)) where the influence of

Bui Xuan Hai

Let $D$ be a division ring with the center $F$ and $D^*$ be the multiplicative group of $D$. In this paper we study locally nilpotent maximal subgroups of $D^*$. We give some conditions that influence the existence of locally nilpotent maximal subgroups in division ring with infinite center. Also, it is shown that if $M$ is a locally nilpotent maximal subgro

Michael Blomqvist, Edvard Mortsell

Inhomogeneous universe models have been proposed as an alternative explanation for the apparent acceleration of the cosmic expansion that does not require dark energy. In the simplest class of inhomogeneous models, we live within a large, spherically symmetric void. Several studies have shown that such a model can be made consistent with many observations, i

Michael Batanin, Denis-Charles Cisinski, Mark Weber

One of the open problems in higher category theory is the systematic construction of the higher dimensional analogues of the Gray tensor product. In this paper we continue the work of [7] to adapt the machinery of globular operads [4] to this task. The resulting theory includes the Gray tensor product of 2-categories and the Crans tensor product [12] of Gray

S. Capozziello, M. De Laurentis, V. Faraoni

We survey the landscape of $f(R)$ theories of gravity in their various formulations, which have been used to model the cosmic acceleration as alternatives to dark energy and dark matter. Besides, we take into account the problem of gravitational waves in such theories. We discuss some successes of $f(R)$-gravity (where $f(R)$ is a generic function of Ricci s

Yoshikata Kida

We compute the automorphism groups of the Torelli complex and the complex of separating curves for all but finitely many compact orientable surfaces. As an application, we show that the abstract commensurators of the Torelli group and the Johnson kernel for such surfaces are naturally isomorphic to the extended mapping class group.

Juergen Herzog, Takayuki Hibi, Freyja Hreinsdottir, Thomas Kahle

We introduce binomial edge ideals attached to a simple graph $G$ and study their algebraic properties. We characterize those graphs for which the quadratic generators form a Gröbner basis in a lexicographic order induced by a vertex labeling. Such graphs are chordal and claw-free. We give a reduced squarefree Gröbner basis for general $G$. It follows that al

Piotr Badziag, Ingemar Bengtsson, Adan Cabello, Helena Granstrom

Klyachko and coworkers consider an orthogonality graph in the form of a pentagram, and in this way derive a Kochen-Specker inequality for spin 1 systems. In some low-dimensional situations Hilbert spaces are naturally organised, by a magical choice of basis, into SO(N) orbits. Combining these ideas some very elegant results emerge. We give a careful discussi

Willie Wai-Yeung Wong

It is shown in this note that a class of Lagrangian field theories closely related to the wave-map equation and the Skyrme model obeys the dominant energy condition, and hence by Hawking&#39;s theorem satisfies finite speed of propagation. The subject matter is a generalization of a recent result of Gibbons.

Y. V. Fyodorov, A. Ossipov, A. Rodriguez

We demonstrate that by considering disordered single-particle Hamiltonians (or their random matrix versions) on ultrametric spaces one can generate an interesting class of models exhibiting Anderson metal-insulator transition. We use the weak disorder virial expansion to determine the critical value of the parameters and to calculate the values of the multif

Jaume Amoros, Monica Manjarin, Marcel Nicolau

In this article we study compact Kähler manifolds $X$ admitting non-singular holomorphic vector fields with the aim of extending to this setting the classical birational classification of projective varieties with tangent vector fields. We prove that any such a Kähler manifold $X$ admits an arbitrarily small deformation of a particular type which is a suspen

Massimo Giovannini

When the last electron-photon scattering takes place in a magnetized environment, the degree of circular polarization of the outgoing radiation depends upon the magnetic field strength. After deriving the scattering matrix of the process, the generalized radiative transfer equations are deduced in the presence of the relativistic fluctuations of the geometry

Tanja Eisner

We study the asymptotic behaviour of contractive operators and strongly continuous semigroups on separable Hilbert spaces using the notion of rigidity. In particular, we show that a &#34;typical&#34; contraction $T$ contains the unit circle times the identity operator in the strong limit set of its powers, while $T^{n_j}$ converges weakly to zero along a seq

Harold Steinacker

We show how Newtonian gravity emerges on 4-dimensional non-commutative spacetime branes in Yang-Mills matrix models. Large matter clusters such as galaxies are embedded in large-scale harmonic deformations of the space-time brane, which screen gravity for long distances. On shorter scales, the local matter distribution reproduces Newtonian gravity via local

Kristian Lindgren

We show that there is a class of stochastic baker&#39;s transformations that is equivalent to the class of equilibrium solutions of two-dimensional spin systems with finite interaction. The construction is such that the equilibrium distribution of the spin lattice is identical to the invariant measure in the corresponding baker&#39;s transformation. We also

Jaime Cuadros

We study null Sasakian structures in dimension five. First, based on a result due to Koll\'ar [Ko], we improve a result by Boyer, Galicki and Matzeu in [BGM] and prove that simply connected manifolds diffeomorphic to $# k(S^2\times S^3)$ admit null Sasaki $\eta$-Einstein structures if and only if $k\in \{3,..., 21\}$. After this, we determine the moduli spac

Otto C. W. Kong, Hung-Yi Lee

Based on a linear realization formulation of a quantum relativity -- the proposed relativity for quantum `space-time&#39;, we introduce the Poincaré-Snyder relativity and Snyder relativity as relativities in between the latter and the well known Galilean and Einstein cases. We discuss how the Poincaré-Snyder relativity may provide a stronger framework for th

Kenzo Inoue, Hirofumi Kubo, Naoki Yamatsu

We consider models with a noncompact symmetry in the framework of $\mathcal{N}=1$ supersymmetry. Contrary to the conventional approach, the noncompact symmetry is realized linearly on all fields without constraints. The models are constructed using noncanonical Kähler function and gauge kinetic function, which is introduced for the local case. It is explaine

Kinjal Banerjee, Aseem Paranjape

We explore in detail the semiclassical environment of collapsing shells of matter, and determine the semiclassical flux measured by a variety of observers. This study is a preliminary step in a broader investigation of thermodynamic properties of the geometry of collapsing objects. Specifically, in this paper we consider spherically symmetric null and timeli

Jian Tang, Walter Winter

The geometric effects of the beam in near detectors at a neutrino factory are discussed. The refined systematics treatment, including cross section errors, flux errors and background uncertainties, is compared with the IDS-NF one. Different near detector setups are included. We also probe their effects both at the measurements of standard neutrino oscillatio

Daniele Tommasini, Albert Ferrando, Humberto Michinel, Marcos Seco

We study how to search for photon-photon scattering in vacuum at present petawatt laser facilities such as HERCULES, and test Quantum Electrodynamics and non-standard models like Born-Infeld theory or scenarios involving minicharged particles or axion-like bosons. First, we compute the phase shift that is produced when an ultra-intense laser beam crosses a l

F. Nesti, R. Percacci

We show how to obtain a single chiral family of an SO(10) GUT, starting from a Majorana-Weyl representation of a unifying (&#34;GraviGUT&#34;) group SO(3,11), which contains the gravitational Lorentz group SO(3,1). An action is proposed, which reduces to the correct fermionic GUT action in the broken phase.

L. J. P. Ament, G. Khaliullin

We present two different theories for Raman scattering and Resonant Inelastic X-ray Scattering (RIXS) in the low temperature ferromagnetic phase of YTiO$_3$ and compare this to the available experimental data. For description of the orbital ground-state and orbital excitations, we consider two models corresponding to two theoretical limits: one where the $t_

Giuseppe Di Bernardo, Carmelo Evoli, Daniele Gaggero, Dario Grasso

We use our numerical code, DRAGON, to study the implications of recent data on our knowledge of the propagation properties of cosmic ray nuclei in the Galaxy. We show that B/C (as well as N/O and C/O) data, including those recently taken by CREAM, and ${\bar p}/p$ data, especially including recent PAMELA results, can consistently be fitted within a unique di

Pedro Macias Marques

It is a longstanding problem in Algebraic Geometry to determine whether the syzygy bundle $E_{d_1,...,d_n}$ on $\mathbb{P}^N$ defined as the kernel of a general epimorphism \[ϕ:\mathcal{O}(-d_1)\oplus...\oplus\mathcal{O}(-d_n) \to\mathcal{O}\] is (semi)stable. In this thesis, attention is restricted to the case of syzygy bundles $\mathrm{Syz}(f_1,...,f_n)$ o

Håvard Haugen, Daniel Huertas-Hernando, Arne Brataas, Xavier Waintal

We investigate the transport properties of three-terminal graphene devices, where one terminal is superconducting and two are normal metals. The terminals are connected by nanoribbons. Electron transfer (ET) and crossed Andreev reflection (CAR) are identified via the non-local signal between the two normal terminals. Analytical expressions for ET and CAR in

Pramod Kumar Mishra

Lattice model of directed self avoiding walk has been solved analytically to investigate adsorption desorption phase transition behaviour of a semiflexible sequential copolymer chain on a two dimensional impenetrable surface perpendicular to the preferred direction of the walk of the copolymer chain in three dimensions. The stiffness of the chain has been ac

Daniel Boer, Piet J. Mulders, Cristian Pisano

The imbalance of dijets produced in hadronic collisions has been used to extract the average transverse momentum of partons inside the hadrons. In this paper we discuss new contributions to the dijet imbalance that could complicate or even hamper this extraction. They are due to polarization of initial state partons inside unpolarized hadrons that can arise

Luis Guijarro, Gerard Walschap

We study submetries between Alexandrov spaces and show how some of the usual features of Riemannian submersions fail due to the lack of smoothness.

Selcen Yuksel Perktas, Erol Kilic, Sadik Keles

In this paper, we study the invariant and noninvariant hypersurfaces of (1,1,1) almost contact manifolds, Lorentzian almost paracontact manifolds and Lorentzian para-Sasakian manifolds, respectively. We show that a noninvariant hypersurface of an (1,1,1) almost contact manifold admits an almost product structure. We investigate hypersurfaces of affinely cosy

D. J. Papoular, G. V. Shlyapnikov, J. Dalibard

We investigate the possibility to control the s-wave scattering length for the interaction between cold bosonic atoms by using a microwave field. Our scheme applies to any atomic species with a ground state that is split by hyperfine interaction. We discuss more specifically the case of alkali-metal atoms and calculate the change in the scattering length for

Hai-Yang Cheng, Chun-Khiang Chua

We reanalyze the $B\to M$ tensor form factors in a covariant light-front quark model, where $M$ represents a vector meson $V$, an axial-vector meson $A$, or a tensor meson $T$. The treatment of masses and mixing angles in the $K_{1A,1B}$ systems is improved, where $K_{1A}$ and $K_{1B}$ are the $^3P_1$ and $^1P_1$ states of the axial-vector meson $K_1$, respe

Benjamin A. Burton, J. Hyam Rubinstein, Stephan Tillmann

In this paper we settle Thurston&#39;s old question of whether the Weber-Seifert dodecahedral space is non-Haken, a problem that has been a benchmark for progress in computational 3-manifold topology over recent decades. We resolve this question by combining recent significant advances in normal surface enumeration, new heuristic pruning techniques, and a ne

Guillaume Roux

We investigate finite size effects in quantum quenches on the basis of simple energetic arguments. Distinguishing between the low-energy part of the excitation spectrum, below a microscopic energy-scale, and the high-energy regime enables one to define a crossover number of particles that is shown to diverge in the small quench limit. Another crossover numbe

Atsuo Kuniba, Tomoki Nakanishi, Junji Suzuki

The T-systems and Y-systems are classes of algebraic relations originally associated with quantum affine algebras and Yangians. Recently the T-systems were generalized to quantum affinizations of a wide class of quantum Kac-Moody algebras by Hernandez. In this note we introduce the corresponding Y-systems and establish a relation between T and Y-systems. We

Yuan-Wei Wu, Ye Xu, Ji Yang, Jing-Jing Li

We present a multi-line study of the massive star-forming region IRAS 22506+5944. A new 6.7 GHz methanol maser was detected. 12CO, 13CO, C18O and HCO+ J = 1-0 transition observations reveal a star formation complex consisting mainly of two cores. The dominant core has a mass of more than 200 solar mass, while another one only about 35 solar mass. Both cores

Lenneke M Jong, Andrew D. Greentree

We show that techniques of spatial adiabatic passage can be used to realise an electron interferometer in a geometry analogous to a conventional Aharonov-Bohm ring, with transport of the particle through the device modulated using coherent transport adiabatic passage. This device shows an interesting interplay between the adiabatic and non-adiabatic behaviou

K. E. Gabanyi, N. Marchili, T. P. Krichbaum, L. Fuhrmann

Short time-scale flux density variations of flat spectrum radio sources are often explained by the scattering of radio waves in the turbulent, ionized Interstellar Matter of the Milky Way. One of the most convincing observational arguments in favor of this is the annual modulation of the variability time-scale caused by the Earth orbital motion around the Su