November 2007 arXiv papers — page 49

Alejo Martinez-Sansigre, Mark Lacy, Anna Sajina, Steve Rawlings

We present mid-infrared observations of 18 sources from a sample of 21 z~2 radio-intermediate obscured quasars. The mid-infrared spectra of the sources are continuum dominated, and 12 sources show deep silicate absorption with tau_9.7~1-2. Combining mid-infrared and optical spectra, we achieve 86% spectroscopic completeness which allows us to confirm that mo

Hua Wei, ZhiJiao Deng, XiaoLong Zhang, Mang Feng

Quantum state transfer and teleportation, with qubits encoded in internal states of the atoms in cavities, among spatially separated nodes of a quantum network in decoherence-free subspace are proposed, based on a cavity-assisted interaction by single-photon pulses. We show in details the implementation of a logic-qubit Hadamard gate and a two-logic-qubit co

Martin W. Sørensen, Anders S. Sørensen

We present a full quantum mechanical three dimensional theory describing an electromagnetic field interacting with an ensemble of identical atoms. The theory is constructed such that it describes recent experiments on light-matter quantum interfaces, where the quantum fluctuations of light are mapped onto the atoms and back onto light. We show that the inter

Yang Sun, Philip M. Walker, Fu-Rong Xu, Yu-Xin Liu

A shape phase transition is demonstrated to occur in 190W by applying the Projected Shell Model, which goes beyond the usual mean-field approximation. Rotation alignment of neutrons in the high-j, i_{13/2} orbital drives the yrast sequence of the system, changing suddenly from prolate to oblate shape at angular momentum 10$\hbar$. We propose observables to t

Sudhir Kumar Singh, Vwani P. Roychowdhury, Himawan Gunadhi, Behnam A. Rezaei

We investigate market forces that would lead to the emergence of new classes of players in the sponsored search market. We report a 3-fold diversification triggered by two inherent features of the sponsored search market, namely, capacity constraints and collusion-vulnerability of current mechanisms. In the first scenario, we present a comparative study of t

Jesper Pedersen, Niels Asger Mortensen

Circular dichroism (CD) is in widespread use as a means of determining enantiomeric excess. We show how slow-light phenomena in dispersive structured media allow for a reduction in the required optical path length of an order of magnitude. The same ideas may be used to enhance the sensitivity of CD measurements while maintaining the same optical path length

T. Mei

At first, we state some results in arXiv: 0707.2639, and then, using a positive kinetic energy coordinate condition given by arXiv: 0707.2639, we present an action with positive kinetic energy term for general relativity. Based on this action, the corresponding theory of canonical quantization is discussed.

Peng Dong, Wei-Tou Ni

In this paper, we use the metric coefficients and the equation of motion in the 2nd post-Newtonian approximation in scalar-tensor theory including intermediate range gravity to derive the deflection of light and compare it with previous works. These results will be useful for precision astrometry missions like GAIA (Global Astrometric Interferometer of Astro

Shuichi Muneta

In this article, we introduce an algebraic setup of non-strict multiple zeta values (NMZVs, for short) and prove some relations of NMZVs, which are analogous to Hoffman's relations of multiple zeta values, by using this algebraic setup of NMZVs.

Telikepalli Kavitha, Rogers Mathew

We present two algorithms for maintaining the topological order of a directed acyclic graph with n vertices, under an online edge insertion sequence of m edges. Efficient algorithms for online topological ordering have many applications, including online cycle detection, which is to discover the first edge that introduces a cycle under an arbitrary sequence

Eugenio Carretta, Alejandra Recio-Blanco, Raffaele G. Gratton, Giampaolo Piotto

We find a strong correlation between the extension of the Na-O anticorrelation observed in red giant branch (RGB) stars and the high temperature extension of the horizontal branch (HB) blue tails of Galactic globular clusters (GCs). The longer is the O-depleted tail of the Na-O anticorrelation observed in the RGB stars, the higher is the maximum temperature

J. Bland-Hawthorn, R. Sutherland, O. Agertz, B. Moore

Since its discovery in 1996, the source of the bright H-alpha emission (up to 750 mR) along the Magellanic Stream has remained a mystery. There is no evidence of ionising stars within the HI stream, and the extended hot halo is far too tenuous to drive strong shocks into the clouds. We now present a hydrodynamical model that explains the known properties of

Hiroshi Ohki, Hideo Matsufuru, Tetsuya Onogi

The B* B pi coupling is a fundamental parameter of chiral effective Lagrangian with heavy-light mesons and can constrain the B->pi l nu form factor in the soft pion limit which will be useful for precise determination of |Vub|. We compute the B* B pi coupling with the static heavy quark and the O(a)-improved Wilson light quark. Simulations are carried out wi

Ken-ichi Nakao, Daisuke Ida, Yasunari Kurita

We investigate an infinitesimally thin cylindrical shell composed of counter-rotating dust particles. This system was studied by Apostolatos and Thorne in terms of the C-energy for a bounded domain. In this paper, we reanalyze this system by evaluating the C-energy on the future null infinity. We find that some class of momentarily static and radiation-free

H. D. Gan, H. Z. Zheng, J. F. Bi, Y. Ji

To clarify whether or not (Ga,Cr)As is an intrinsic diluted magnetic semiconductor, a systematic study of the magnetic circular dichroism (MCD) was carried out for a series of (Ga,Cr)As epilayers grown by the low-temperature molecular-beam epitaxy technique. The present work provides unambiguous evidence for the intrinsic ferromagnetism of the (Ga,Cr)As epil

Yitwah Cheung, Alex Eskin

Masur showed that a Teichmuller geodesic that is recurrent in the moduli space of closed Riemann surfaces is necessarily determined by a quadratic differential with a uniquely ergodic vertical foliation. In this paper, we show that a divergent Teichmuller geodesic satisfying a certain slow rate of divergence is also necessarily determined by a quadratic diff

Lauren A. MacArthur, Richard S. Ellis, Tommaso Treu, Vivian U

We report on the first results of a new study aimed at understanding the diversity and evolutionary history of distant galactic bulges in the context of now well-established trends for pure spheroidal galaxies. To this end, bulges have been isolated for a sample of 137 spiral galaxies within the redshift range 0.1<z<1.2 in the GOODS fields. Using proven phot

Hyun Seok Yang

We argue that a field theory defined on noncommutative (NC) spacetime should be regarded as a theory of gravity, which we refer to as the emergent gravity. A whole point of the emergent gravity is essentially originated from the basic property: A NC spacetime is a (NC) phase space. This fact leads to two important consequences: (I) A NC field theory can basi

Chung Kao, Duane Dicus, Rahul Malhotra, Yili Wang

We investigate the prospects for the discovery at the CERN Large Hadron Collider or at the Fermilab Tevatron of neutral Higgs bosons through the channel where the Higgs are produced together with a single bottom quark and the Higgs decays into a pair of tau leptons, $bg \to bϕ^0 \to bτ^+τ^-, ϕ^0 = h^0, H^0, A^0$. We work within the framework of the minimal s

E. W. Rosolowsky, J. E. Pineda, J. B. Foster, M. A. Borkin

We present ammonia observations of 193 dense cores and core candidates in the Perseus molecular cloud made using the Robert F. Byrd Green Bank Telescope. We simultaneously observed the NH3(1,1), NH3(2,2), CCS (2_1 -> 1_0) and CC34S (2_1 -> 1_0) transitions near 23 GHz for each of the targets with a spectral resolution of dv ~ 0.024 km/s. We find ammonia emis

Judith Brinkschulte, C. Denson Hill, Mauro Nacinovich

In Grauert&#39;s paper [G] it is noted that finite dimensionality of cohomology groups sometimes implies vanishing of these cohomomogy groups. Later on Laufer formulated a zero or infinity law for the cohomology groups of domains in Stein manifolds. In this paper we generalize Laufer&#39;s Theorem in [L] and its version for small domains of CR manifolds, pro

Judith Brinkschulte, C. Denson Hill, Mauro Nacinovich

For pseudoconvex abstract CR manifolds, the validity of the Poincare Lemma for (0,1) forms implies local embeddability in C^N. The two properties are equivalent for hypersurfaces of real dimension > or = 5. As a corollary we obtain a criterion for the non validity of the Poicare Lemma for (0,1) forms for a large class of abstract CR manifolds of CR codimensi

Alexander Shatskiy

A spherically symmetric evolution model of self-gravitating matter with the equation of state P=wE (where w=const<-1) is considered. The equations of the model are written in the frame of reference comoving with matter. A criterion for the existence and formation of a horizon is defined. Part of the Einstein equations is integrated analytically. The initial

Judith Brinkschulte, C. Denson Hill, Mauro Nacinovich

In this paper, we consider the boundary M of a weakly pseudoconvex domain in a Stein manifold. We point out a striking difference between the local cohomology and the global cohomology of M, and illustrate this with an example. We also discuss the first and second Cousin problems, and the strong Poincare problem for CR meromorphic functions on the weakly pse

Judith Brinkschulte, C. Denson Hill, Mauro Nacinovich

We make two tiny corrections to our previous paper with the same title, and also obtain, as a bonus, something new.

L. J. Dursi, C. Pfrommer

High-resolution X-ray observations have revealed cavities and `cold fronts&#39; with sharp edges in temperature, density, and metallicity within galaxy clusters. Their presence poses a puzzle since these features are not expected to be hydrodynamically stable, or to remain sharp in the presence of diffusion. However, a moving core or bubble in even a very we

V. S. Zotev, A. N. Matlashov, P. L. Volegov, I. M. Savukov

One of the challenges in functional brain imaging is integration of complementary imaging modalities, such as magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI). MEG, which uses highly sensitive superconducting quantum interference devices (SQUIDs) to directly measure magnetic fields of neuronal currents, cannot be combined with co

C. A. Ballon Bayona, Henrique Boschi-Filho, Nelson R. F. Braga

Deep inelastic structure functions have been calculated by Polchinski and Strassler in gauge/string duality introducing a hard infrared (IR) cut off in AdS space. Here we investigate this problem using a soft IR cut off that leads to linear Regge trajectories for mesons. We calculate the structure functions for scalar particles in the large x regime where su

Gerald E. Marsh

It will be argued here that the cosmological constant problem exists because of the way the vacuum is defined in quantum field theory. It has been known for some time that for QFT to be gauge invariant certain terms--such as part of the vacuum polarization tensor--must be eliminated either explicitly or by some form of regularization followed by renormalizat

Wonkee Kim, F. Marsiglio, C. S. Ting

We calculate the Hall conductivity for a spin-triplet superconductor, using a generalized pairing symmetry dependent on an arbitrary phase, $\vphi$. A promising candidate for such an order parameter is Sr$_{2}$RuO$_{4}$, whose superconducting order parameter symmetry is still subject to investigation. The value of this phase can be determined through Kerr ro

M. Grigoriev, A. A. Tseytlin

Motivated by a desire to find a useful 2d Lorentz-invariant reformulation of the AdS_5 x S^5 superstring world-sheet theory in terms of physical degrees of freedom we construct the Pohlmeyer-reduced version of the corresponding sigma model. The Pohlmeyer reduction procedure involves several steps. Starting with a coset space string sigma model in the conform

William Breslin

We show that a complete hyperbolic n-manifold has a geodesic triangulation such that the tetrahedra contained in the thick part are L-bilipschitz diffeomorphic to the standard Euclidean n-simplex, for some constant L depending only on the dimension and the constant used to define the thick-thin decomposition of M.

Christian Léonard

Generalized entropic projections and dominating points are solutions to convex minimization problems related to conditional laws of large numbers. They appear in many areas of applied mathematics such as statistical physics, information theory, mathematical statistics, ill-posed inverse problems or large deviation theory. By means of convex conjugate duality

S. Risau-Gusman, F. Roma

We study directly the length of the domain walls (DW) obtained by comparing the ground states of the Edwards-Anderson spin glass model subject to periodic and antiperiodic boundary conditions. For the bimodal and Gaussian bond distributions, we have isolated the DW and have calculated directly its fractal dimension $d_f$. Our results show that, even though i

Andrey Penzev, Yoshinori Yasuta, Minoru Kubota

Detailed studies of AC velocity Vac and temperature dependence of torsional oscillator responses of solid 4He are reported. A characteristic onset temperature T0 about 0.5 K is found, below which a significant Vac dependent change occurs in the energy dissipation for the sample at 32 bar. A Vac dependence of the non-classical rotational inertia fraction, NCR

S. G. Turyshev, U. E. Israelsson, M. Shao, N. Yu

Space-based experiments today can uniquely address important questions related to the fundamental laws of Nature. In particular, high-accuracy physics experiments in space can test relativistic gravity and probe the physics beyond the Standard Model; they can perform direct detection of gravitational waves and are naturally suited for precision investigation

Andrei Mikhailov, Sakura Schafer-Nameki

We propose an action for a sine-Gordon-like theory, which reproduces the classical equations of motion of the Green-Schwarz-Metsaev-Tseytlin superstring on AdS(5) x S(5). The action is relativistically invariant. It is a mass-deformed gauged WZW model for SO(4,1) x SO(5) / SO(4) x SO(4) interacting with fermions.

Olaf Lenz, Christian Holm

We have performed MD simulations of a highly charged colloid in a solution of 3:1 and additional 1:1 salt. The dependency of the colloid&#39;s inverted charge on the concentration of the additional 1:1 salt has been studied. Most theories predict, that the inverted charge increases when the concentration of monovalent salt grows, up to what is called &#34;gi

Sebastiano Albergo

The discovery potentials of ATLAS and CMS experiments at the Large Hadron Collider (LHC) for Supersimmetry (SUSY), Extra Dimensions (ED), new Gauge Bosons and R-Hadrons are discussed. Beyond Standard-Model (BSM) searches at LHC require a detailed understanding of the detector performance, reconstruction algorithms and triggering. Precision measurements of St

Dexter Kozen

We give an explicit coinduction principle for recursively-defined stochastic processes. The principle applies to any closed property, not just equality, and works even when solutions are not unique. The rule encapsulates low-level analytic arguments, allowing reasoning about such processes at a higher algebraic level. We illustrate the use of the rule in der

Paul H. Frampton, Thomas W. Kephart

The entropy in the interior of the Universe has many contributions including well understood ones from radiation and relic neutrinos. The gravitational entropy is larger and more subtle. One contribution which provides our lower bound is from supermassive black holes at the centers of galaxies. The remainder is harder to pin down. We suggest an upper bound w

V. A. Dolgushev, V. N. Rubtsov

The formality theorem for Hochschild chains of the algebra of functions on a smooth manifold gives us a version of the trace density map from the zeroth Hochschild homology of a deformation quantization algebra to the zeroth Poisson homology. We propose a version of the algebraic index theorem for a Poisson manifold which is based on this trace density map.

D. V. Bowen, E. B. Jenkins, T. M. Tripp, K. R. Sembach

To probe the distribution and physical characteristics of interstellar gas at temperatures T ~ 3e5 K in the disk of the Milky Way, we have used the Far Ultraviolet Spectroscopic Explorer (FUSE) to observe absorption lines of OVI toward 148 early-type stars situated at distances 1 kpc. After subtracting off a mild excess of OVI arising from the Local Bubble,

Erich J. Mueller

We show that bimodal radio frequency spectra universally arise at intermediate temperatures in models of strongly interacting trapped Fermi gases. The bimodality is independent of superfluidity or pseudogap physics, depending only on the functional form of the equation of state -- which is constrained by dimensional analysis at low temperatures and the viria

D. Grumiller, R. Jackiw

We discuss the Kaluza-Klein reduction of spaces with (anti-)self-dual Weyl tensor and point out the emergence of the Einstein-Weyl equations for the reduction from four to three dimensions. As a byproduct we get a simple expression for the gravitational instanton density in terms of the Kaluza-Klein functions.

Stjepan Meljanac, Zoran Škoda

Given a finite-dimensional Lie algebra, and a representation by derivations on the completed symmetric algebra of its dual, a number of interesting twisted constructions appear: certain twisted Weyl algebras, deformed Leibniz rules, quantized ``star&#39;&#39; product. We first illuminate a number of interrelations between these constructions and then proceed

Anoosheh Niavarani, Nikolai V. Priezjev

Molecular dynamics simulations are carried out to investigate the dynamic behavior of the slip length in thin polymer films confined between atomically smooth thermal surfaces. For weak wall-fluid interactions, the shear rate dependence of the slip length acquires a distinct local minimum followed by a rapid growth at higher shear rates. With increasing flui

Ronnie Jansson, Glennys R. Farrar

We generalize the Maximum Likelihood-type method used to study cross correlations between a catalog of candidate astrophysical sources and Ultrahigh Energy Cosmic Rays (UHECRs), to allow for differing source luminosities. The new method is applicable to any sparse data set such as UHE gamma rays or astrophysical neutrinos. Performance of the original and gen

Sandip Pakvasa, Werner Rodejohann, Thomas J. Weiler

Current experimental data on neutrino mixing are very well described by TriBiMaximal mixing. Accordingly, any phenomenological parametrization of the MNSP matrix must build upon TriBiMaximal mixing. We propose one particularly natural parametrization, which we call &#34;TriMinimal&#34;. The three small deviations of the PDG angles from their TriBiMaximal val

T. W. Brown, P. J. Heslop, S. Ramgoolam

We present a complete basis of multi-trace multi-matrix operators that has a diagonal two point function for the free matrix field theory at finite N. This generalises to multiple matrices the single matrix diagonalisation by Schur polynomials. Crucially, it involves intertwining the gauge group U(N) and the global symmetry group U(M) with Clebsch-Gordan coe

K. Giesel, S. Hofmann, T. Thiemann, O. Winkler

Linear cosmological perturbation theory is pivotal to a theoretical understanding of current cosmological experimental data provided e.g. by cosmic microwave anisotropy probes. A key issue in that theory is to extract the gauge invariant degrees of freedom which allow unambiguous comparison between theory and experiment. When one goes beyond first (linear) o

A. J. Behan, A. Mokhtari, H. J. Blythe, D. Score

Films of ZnO doped with magnetic ions, Mn and Co and, in some cases, with Al have been fabricated with a very wide range of carrier densities. Ferromagnetic behaviour is observed in both insulating and metallic films, but not when the carrier density is intermediate. Insulating films exhibit variable range hopping at low temperatures and are ferromagnetic at

T. L. Todorova, D. I. Tolev

A classical problem in analytic number theory is to study the distribution of $αp$ modulo 1, where $α$ is irrational and $p$ runs over the set of primes. We consider the subsequence generated by the primes $p$ such that $p+2$ is an almost-prime (the existence of infinitely many such $p$ is another topical result in prime number theory) and prove that its dis

Charlie Conroy, Alice E. Shapley, Jeremy L. Tinker, Michael R. Santos

Star-forming galaxies constitute the majority of galaxies with stellar masses >10^10 M_Sun/h^2 at z~2 and dominate the star-formation rate density of the Universe at this early epoch. It is thus critical to understand their origins, evolution, and connection to the underlying dark matter distribution. To this end, we identify the dark matter halos (including

Poul H. Damgaard, Thomas DeGrand, Hidenori Fukaya

In the chiral limit of QCD, the pion decay constant F can be extracted from lattice gauge theory by means of a coupling to isospin chemical potential. Here we compute the leading correction due to finite volume in the epsilon-expansion of chiral perturbation theory. A comparison is made to recent Monte Carlo data.

Asger Tornquist, William Weiss

We prove the following analogue of a Theorem of R.O. Davies: Every $Σ^1_2$ function $f:\R\times\R\to\R$ can be represented as a sum of rectangular $Σ^1_2$ functions if and only if all reals are constructible.

D0 Collaboration, V. M. Abazov

We present the first model-independent measurement of the helicity of $W$ bosons produced in top quark decays, based on a 1 fb$^{-1}$ sample of candidate $t\bar{t}$ events in the dilepton and lepton plus jets channels collected by the D0 detector at the Fermilab Tevatron $p\bar{p}$ Collider. We reconstruct the angle $θ^*$ between the momenta of the down-type

P. E. Bosted, M. E. Christy

An empirical fit is described to measurements of inclusive inelastic electron-deuteron cross sections in the kinematic r ange of four-momentum transfer $0 \le Q^2<10$ GeV$^2$ and final state invariant mass $1.1<W<3.2$ GeV. The deuteron fit relies on a fit of the ratio $R_p$ of longitudinal to transverse cross sections for the proton, and the assumption $R_p=

Asger Tornquist

We prove that orbit equivalence of measure preserving ergodic a.e. free actions of a countable group with the relative property (T) is a complete analytic equivalence relation.

Richard Durran, Andrew Neate, Aubrey Truman

We consider the Bohr correspondence limit of the Schrodinger wave function for an atomic elliptic state. We analyse this limit in the context of Nelson&#39;s stochastic mechanics, exposing an underlying deterministic dynamical system in which trajectories converge to Keplerian motion on an ellipse. This solves the long standing problem of obtaining Kepler&#3

John P. Perdew, Adrienn Ruzsinszky, Gabor I. Csonka, Oleg A. Vydrov

Successful modern generalized gradient approximations (GGA&#39;s) are biased toward atomic energies. Restoration of the first-principles gradient expansion for exchange over a wide range of density gradients eliminates this bias. We introduce PBEsol, a revised Perdew-Burke-Ernzerhof GGA that improves equilibrium properties of densely-packed solids and their

J. A. Tjon, W. Melnitchouk

We compute the corrections from two-photon and photon-Z exchange in parity-violating elastic electron-proton scattering, used to extract the strange form factors of the proton. We use a hadronic formalism that successfully reconciled the earlier discrepancy in the proton&#39;s electron to magnetic form factor ratio, suitably extended to the weak sector. Impl

Jonathan Engle, Etera Livine, Roberto Pereira, Carlo Rovelli

We extend the definition of the &#34;flipped&#34; loop-quantum-gravity vertex to the case of a finite Immirzi parameter. We cover the Euclidean as well as the Lorentzian case. We show that the resulting dynamics is defined on a Hilbert space isomorphic to the one of loop quantum gravity, and that the area operator has the same discrete spectrum as in loop qu

Nikolaos Kidonakis

I present analytical expressions for the collinear and soft gluon corrections to Higgs production via the process b bbar -> H as well as gg -> H through next-to-next-to-next-to-leading order (NNNLO). The soft corrections are complete while the collinear corrections include leading and some subleading logarithms. Numerical results at the Tevatron and the LHC

Erwin Bolthausen, Francesco Caravenna, Béatrice de Tilière

We consider a model for a polymer interacting with an attractive wall through a random sequence of charges. We focus on the so-called diluted limit, when the charges are very rare but have strong intensity. In this regime, we determine the quenched critical point of the model, showing that it is different from the annealed one. The proof is based on a rigoro

Winfried Just, German A. Enciso

Discrete dynamical systems defined on the state space {0,1,...,p-1}^n have been used in multiple applications, most recently for the modeling of gene and protein networks. In this paper we study to what extent well-known theorems by Smale and Hirsch, which form part of the theory of (continuous) monotone dynamical systems, generalize or fail to do so in the

Suvankar Dutta, Rajesh Gopakumar

The dynamics of finite temperature U(N) gauge theories on $S^3$ can be described, at weak coupling, by an effective unitary matrix model. Here we present an exact solution to these models, for any value of $N$, in terms of a sum over representations. Taking the large $N$ limit of this solution provides a new perspective on the deconfinement transition which

Simon Wassermann

It is shown that if $C_1$ and $C_2$ are maximal abelian self-adjoint subalgebras (masas) of C*-algebras $A_1$ and $A_2$, respectively, then the completion $C_1\otimes C_2$ of the algebraic tensor product $C_1\odot C_2$ of $C_1$ and $C_2$ in any C*-tensor product $A_1\otimes_β A_2$ is maximal abelian provided that $C_1$ has the extension property of Kadison a

I. O. Thomas, V. V. Kabanov, A. S. Alexandrov

We analyze the behavior of the longitudinal conductivity $σ_{zz}$ in a field perpendicular to the highly conducting plane of a quasi-2D {\em multiband} metal in the case of closed system and open systems where $τ$ is fixed, $τ$ oscillates due to intra-band scattering and $τ$ oscillates due to inter-band scattering. In all but one case, we find that there are

Paul Fendley, Vyacheslav Krushkal

This paper introduces a conceptual framework, in the context of quantum topology and the algebras underlying it, for analyzing relations obeyed by the chromatic polynomial χ(Q) of planar graphs. Using it we give new proofs and substantially extend a number of classical results concerning the combinatorics of the chromatic polynomial. In particular, we show t

A. M. Bobkov, I. V. Bobkova

The influence of the atomic-scale inhomogeneities of the pairing interaction on the superconducting order parameter distribution and the LDOS is studied in the framework of mean-field BCS theory for two-dimensional lattice model. It is found that the ratio of the local low-temperature gap in differential conductance to the local temperature of vanishing the

Qionglei Chen, Changxing Miao, Zhifei Zhang

We improve and extend some known regularity criterion of weak solution for the 3D viscous Magneto-hydrodynamics equations by means of the Fourier localization technique and Bony&#39;s para-product decomposition.

Roberto Auzzi, Minoru Eto, Walter Vinci

Interactions between non-BPS non-Abelian vortices are studied in non-Abelian U(1) x SU(N) extensions of the Abelian-Higgs model in four dimensions. The distinctive feature of a non-Abelian vortex is the presence of an internal CP^{N-1} space of orientational degrees of freedom. For fine-tuned values of the couplings, the vortices are BPS and there is no net

Ingo Runkel

Defect lines in conformal field theory can be perturbed by chiral defect fields. If the unperturbed defects satisfy su(2)-type fusion rules, the operators associated to the perturbed defects are shown to obey functional relations known from the study of integrable models as T-systems. The procedure is illustrated for Virasoro minimal models and for Liouville

Robert S. Whitney

The perturbative master equation (Bloch-Redfield) is extensively used to study dissipative quantum mechanics - particularly for qubits - despite the 25 year old criticism that it violates positivity (generating negative probabilities). We take an arbitrary system coupled to an environment containing many degrees-of-freedom, and cast its perturbative master e

Milos V. Lokajicek

In the past century it was believed that both the main theories (quantum mechanics and special relativity) predicted the existence of physical processes that could not be explained in the framework of classical physics. However, it has been shown recently that the solutions of Schroedinger equation have described the physical situation practically in full ag

Hristu Culetu

A spacetime endowed with an anisotropic fluid is proposed for the interior of a Schwarzschild black hole. The geometry has an instantaneous Minkowski form and is a solution of Einstein&#39;s equations with a stress tensor on the r.h.s. obeying all the energy conditions. The interior fluid is compressible, with time dependent shear and bulk viscosity coeffici

Yuri Ozhigov

The simple genetic algorithm is proposed for the simulation of quantum many body dynamics. It uses the selection of entangled quantum states and has the inbuilt absolute decoherence that comes from the limitation of classical memory. It utilizes the &#34;pre-quantum field&#34; in the form of interacting between the different &#34;quantum worlds&#34;. It is s

Yoichi Aso, Zsuzsa Marka, Chad Finley, John Dwyer

We present a coincidence search method for astronomical events using gravitational wave detectors in conjunction with other astronomical observations. We illustrate our method for the specific case of the LIGO gravitational wave detector and the IceCube neutrino detector. LIGO trigger-events and IceCube events which occur within a given time window are selec

Gyan Prakash

Let $G$ be a finite abelian group of order $n$. For any subset $B$ of $G$ with $B=-B$, the Cayley graph $G_B$ is a graph on vertex set $G$ in which $ij$ is an edge if and only if $i-j\in B.$ It was shown by Ben Green that when $G$ is a vector space over a finite field $Z/pZ$, then there is a Cayley graph containing neither a complete subgraph nor an independ

Yuri Kornyushin

Present paper is a review of results, obtained in the framework of semiclassical approach in nanophysics. Semiclassical description, based on Electrostatics and Thomas-Fermi model was applied to calculate dimensions of the electronic shell of a fullerene molecule and a carbon nanotube. This simplified approach yields surprisingly accurate results in some cas

Brent Everitt, Paul Turner

We define a homology theory for a certain class of posets equipped with a representation. We show that when restricted to Boolean lattices this homology is isomorphic to the homology of the &#34;cube&#34; complex defined by Khovanov.

V. Apaja, M. Saarela

We present diffusion Monte Carlo (DMC) results on a new metastable, superfluid phase above the crystal ground state in two-dimensional 4He at densities > 0.065 1/A^2. The state is anisotropic with hexatic orbital order. This implies that the liquid--solid phase transition has two stages: A second order phase transition from the isotropic superfluid to the he

C. D. Hu

We studied the microscopic mechanism of multiferroics, in particular with the &#34;spin current&#34; model (Hosho Katsura, Naoto Nagaosa and Aleander V. Balatsky, Phys. Rev. Lett. 95, 057205 (2005)). Starting from a system with helical spin configuration, we solved for the forms of the electron wave functions and analyzed their characteristics. The relation

Szymon Gladysz, Julian C. Christou

We propose a new post-processing technique for the detection of faint companions from a sequence of adaptive optics corrected short exposures. The algorithm exploits the difference in shape between the on-axis and off-axis irradiance distributions and it does not require the signal to be above the noise level. We show that the method is particularly useful i

Eon-Kyung Lee, Sang-Jin Lee

Let $G$ be one of the Artin groups of finite type ${\mathbf B}_n={\mathbf C}_n$, and affine type $\tilde{\mathbf A}_{n-1}$ and $\tilde{\mathbf C}_{n-1}$. In this paper, we show that if $α$ and $β$ are elements of $G$ such that $α^k=β^k$ for some nonzero integer $k$, then $α$ and $β$ are conjugate in $G$. For the Artin group of type $\mathbf A_n$, this was re

Samuel Grushevsky

In this survey we give a brief introduction to, and review the progress made in the last decade in understanding the geometry of the moduli spaces A_g of principally polarized abelian varieties and its compactifications. Topics surveyed include: compactifications; birational geometry: nef and effective cones, canonical models; homology, Chow rings and inters

A. S. Alexandrov

Magneto-oscillations in kinetic and magnetic response functions of a few underdoped cuprates are perhaps one of the most striking observations since many probes of underdoped cuprates clearly point to a non Fermi-liquid normal state. Their observation in the vortex state well below the upper critical field raises a doubt concerning their normal state origin.

Takeshi Oota, Yukinori Yasui

It is shown that the Dirac equations in general higher dimensional Kerr-NUT-de Sitter spacetimes are separated into ordinary differential equations.

Sergey Gubin

Reducing the NP-problems to the convex/linear analysis on the Birkhoff polytope.

Yilmaz Simsek

By using q-Volkenborn integral on Z_{p}, we (simsek, simsekCanada) constructed new generating functions of the (h,q)-Bernoulli polynomials and numbers. By applying the Mellin transformation to the generating functions, we constructed integral representation of the twisted (h,q)-Hurwitz function and twisted (h,q)-two-variable L-function. By using these functi

Changhyun Ahn

Starting from an N=1 supersymmetric electric gauge theory with the multiple product gauge group and the bifundamentals, we apply Seiberg dual to each gauge group, obtain the N=1 supersymmetric dual magnetic gauge theories with dual matters including the gauge singlets. Then we describe the intersecting brane configurations, where there are NS-branes and D4-b

Ruth Durrer, Roy Maartens

Observations provide increasingly strong evidence that the universe is accelerating. This revolutionary advance in cosmological observations confronts theoretical cosmology with a tremendous challenge, which it has so far failed to meet. Explanations of cosmic acceleration within the framework of general relativity are plagued by difficulties. General relati

Satoshi Naito, Daisuke Sagaki

We give an explicit description of the (lowering) Kashiwara operators on Mirković-Vilonen polytopes in types $B$ and $C$, which provides a simple method for generating Mirković-Vilonen polytopes inductively. This description can be thought of as a modification of the original Anderson-Mirković conjecture, which Kamnitzer proved in the case of type $A$, and p

Jiuzu Hong

Let $G$ be a connected, simply-connected, and almost simple algebraic group, and let $\sigma$ be a Dynkin automorphism on $G$. In this paper, we get a bijection between the set of $\st$-invariant MV cycles (polytopes) for $G$ and the set of MV cycles (polytopes) for $G^\st$, which is the fixed point subgroup of $G$; moreover, this bijection can be restricted

Svetlin Tassev, Edmund Bertschinger

When thin accretion disks around black holes are perturbed, the main restoring force is gravity. If gas pressure, magnetic stresses, and radiation pressure are neglected, the disk remains thin as long as orbits do not intersect. Intersections would result in pressure forces which limit the growth of perturbations. We find that a discrete set of perturbations

Dipankar Das, Vasant Natarajan

We have measured hyperfine structure in the first-excited $P$ state ($D$ lines) of all the naturally-occurring alkali atoms. We use high-resolution laser spectroscopy to resolve hyperfine transitions, and measure intervals by locking the frequency shift produced by an acousto-optic modulator to the difference between two transitions. In most cases, the hyper

Ahsan Nazir

Photon correlations in the emission of a resonantly driven quantum dot are investigated, accounting for the influence of the solid-state phonon environment. An analytical expression is derived for the second-order fluorescence intensity correlation function, from which regimes of correlated and uncorrelated photon emission are predicted as the driving field

S. M. Iftiquar, G. R. Karve, Vasant Natarajan

We obtain subnatural linewidth (i.e. $<Γ$) for probe absorption in room-temperature Rb vapor using electromagnetically induced transparency (EIT) in a $Λ$ system. For stationary atoms, the EIT dip for a resonant control laser is as wide as the control Rabi frequency $Ω_c$. But in thermal vapor, the moving atoms fill the transparency band so that the final EI

Z. Wei, A. Sharma, J. Bass, M. Tsoi

We report the first measurements of effects of large current densities on current-perpendicular-to-plane magnetoresistance (MR) of magnetic multilayers containing two antiferromagnetic layers separated by a non-magnetic layer. These measurements were intended to search for a recently predicted antiferromagnetic giant magnetoresistance (AGMR) similar to GMR s