May 2009 arXiv papers — page 25
Showing 2,401–2,500 of 5,084 papers
C. F. Berger, Z. Bern, L. J. Dixon, F. Febres Cordero
In this talk, we report on a recent next-to-leading order QCD calculation of the production of a W boson in association with three jets at hadron colliders. The computation is performed by combining two programs, BlackHat for the computation of the virtual one-loop matrix elements and Sherpa for the real emission part.
Temperature dependence of hydrogen local mode frequencies in the ordering bcc metal hydrides
cond-mat.mtrl-sciI. G. Ratishvili, N. Z. Namoradze
A simple physical conception explaining the experimentally observed temperature dependence of the local mode frequencies in the ordering metal hydrides is proposed. Calculations are performed for bcc vanadium deuterides. The model can be applied to other physical phenomena which are related to the hydrogen motion in metal lattices.
Feng Qi, Senlin Guo, Bai-Ni Guo
In the present paper, we establish necessary and sufficient conditions for the functions $x^α\bigl\lvertψ^{(i)}(x+β)\bigr\lvert$ and $α\bigl\lvertψ^{(i)}(x+β)\bigr\lvert-x\bigl\lvertψ^{(i+1)}(x+β)\bigr\lvert$ respectively to be monotonic and completely monotonic on $(0,\infty)$, where $i\in\mathbb{N}$, $α>0$ and $β\ge0$ are scalars, and $ψ^{(i)}(x)$ are poly
Analytical solutions of the Schrödinger equation with the Woods-Saxon potential for arbitrary $l$ state
math-phV. H. Badalov, H. I. Ahmadov, A. I. Ahmadov
In this work, the analytical solution of the radial Schrödinger equation for the Woods-Saxon potential is presented. In our calculations, we have applied the Nikiforov-Uvarov method by using the Pekeris approximation to the centrifugal potential for arbitrary $l$ states. The bound state energy eigenvalues and corresponding eigenfunctions are obtained for var
Ahmadjon Abdujabbarov, Bobomurat Ahmedov
Analytical solutions of Maxwell equations in background spacetime of black hole in braneworld immersed in external uniform magnetic field have been found. Influence of both magnetic and brane parameters on effective potential of the radial motion of charged test particle around slowly rotating black hole in braneworld immersed in uniform magnetic field has b
Hiroyuki Kawamura, Kazuhiro Tanaka
The $B$-meson light-cone distribution amplitude (LCDA) is defined as the matrix element of a quark-antiquark bilocal light-cone operator in the heavy-quark effective theory (HQET) and is a building block of QCD factorization formula for exclusive $B$-meson decays. When the corresponding bilocal HQET operator has a light-like distance $t$ between the quark an
Hideyuki Mori, Yoshiaki Hyodo, Takeshi Go Tsuru, Masayoshi Nobukawa
A 20' \times 16' elliptical ring-like structure has been found near the Galactic center in the narrow energy band corresponding to the K$α$ line from He-like sulfur. In the ring, two diffuse sources are found, a supernova remnant candidate G359.79-0.26 and an unidentified source G359.77-0.09. The X-ray spectrum of G359.77-0.09 is similar to that of G
Xing Li, Yonghui Wu, Zhihai Rong, Zhongzhi Zhang
The conventional wisdom is that scale-free networks are prone to cooperation spreading. In this paper we investigate the cooperative behaviors on the structured scale-free network. On the contrary of the conventional wisdom that scale-free networks are prone to cooperation spreading, the evolution of cooperation is inhibited on the structured scale-free netw
M. Bukai, A. Eidelman, T. Elperin, N. Kleeorin
We study an effect of large-scale coherent structures on global properties of turbulent convection in laboratory experiments in air flow in a rectangular chamber with aspect ratios $A \approx 2$ and $A\approx 4$ (with the Rayleigh numbers varying in the range from $5 \times 10^6$ to $10^8$). The large-scale coherent structures comprise the one-cell and two-c
Edward Witten
Geometric Langlands duality is usually formulated as a statement about Riemann surfaces, but it can be naturally understood as a consequence of electric-magnetic duality of four-dimensional gauge theory. This duality in turn is naturally understood as a consequence of the existence of a certain exotic supersymmetric conformal field theory in six dimensions.
Achievable Rate and Optimal Physical Layer Rate Allocation in Interference-Free Wireless Networks
cs.ITTao Cui, Tracey Ho, Joerg Kliewer
We analyze the achievable rate in interference-free wireless networks with physical layer fading channels and orthogonal multiple access. As a starting point, the point-to-point channel is considered. We find the optimal physical and network layer rate trade-off which maximizes the achievable overall rate for both a fixed rate transmission scheme and an impr
O. P. Sushkov
The idea of condensation of the Goldstone $π$-meson field in nuclear matter had been put forward a long time ago. However, it was established that the normal nuclear density is too low, it is not sufficient to condensate $π$-mesons. This is why the $π$-condensation has never been observed. Recent experimental and theoretical studies of high temperature cupra
Qiang Lin, Jessie Rosenberg, Xiaoshun Jiang, Kerry J. Vahala
In this work we combine the large per-photon optical gradient force with the sensitive feedback of a high quality factor whispering-gallery microcavity. The cavity geometry, consisting of a pair of silica disks separated by a nanoscale gap, shows extremely strong dynamical backaction, powerful enough to excite giant coherent oscillations even under heavily d
Dmitriy Melnikov, Guinevere Strack, Marcos Pita, Vladimir Privman
In this work we demonstrate both experimentally and theoretically that the analog noise generation by a single enzymatic logic gate can be dramatically reduced to yield gate operation with virtually no input noise amplification. This is achieved by exploiting the enzyme's specificity when using a co-substrate that has a much lower affinity than the prima
Areejit Samal, Hildegard Meyer-Ortmanns
We study a model for the evolution of chemical species under a combination of population dynamics on a short time scale and a selection mechanism on a longer time scale. Least fit nodes are replaced by new nodes whose links are attached to the nodes of the given network via preferential attachment. In contrast to a random attachment of newly incoming nodes t
Conservation of high-flux backbone in alternate optimal and near-optimal flux distributions of metabolic networks
q-bio.MNAreejit Samal
Constraint-based flux balance analysis (FBA) has proven successful in predicting the flux distribution of metabolic networks in diverse environmental conditions. FBA finds one of the alternate optimal solutions that maximizes the biomass production rate. Almaas et al have shown that the flux distribution follows a power law, and it is possible to associate w
Alexander Friedland, Maurizio Giannotti, Michael Graesser
Unparticle behavior is shown to be realized in the Randall-Sundrum 2 (RS 2) and the Lykken-Randall (LR) brane scenarios when brane-localized Standard Model currents are coupled to a massive vector field living in the five-dimensional warped background of the RS 2 model. By the AdS/CFT dictionary these backgrounds exhibit certain properties of the unparticle
Programming Realization of Symbolic Computations for Non-linear Commutator Superalgebras over the Heisenberg--Weyl Superalgebra: Data Structures and Processing Methods
hep-thA. Kuleshov, A. A. Reshetnyak
We suggest a programming realization of an algorithm for verifying a given set of algebraic relations in the form of a supercommutator multiplication table for the Verma module, which is constructed according to a generalized Cartan procedure for a quadratic superalgebra and whose elements are realized as a formal power series with respect to non-commuting e
Noam Soker
I propose a feedback model to explain the correlation between the supermassive black hole (SMBH) mass and the host galaxy bulge mass. The feedback is based on narrow jets that are launched by the central SMBH, and expel large amounts of mass to large distances. The condition is that the jets do not penetrate through the inflowing gas, such that they can depo
Shamik Banerjee, Rajesh Kumar Gupta
It is known that non-holomorphic corrections are necessary in order to get duality invariant free energy and entropy function. However the present methods of incorporating non-holomorphic corrections are in conflict with special geometry properties of moduli space. The moduli fields do not transform in duality covariant way and their duality transformation a
A. L. Agore
We prove that both, the embedding of the category of Hopf algebras into that of bialgebras and the forgetful functor from the category of Hopf algebras to the category of algebras, have right adjoints; in other words: every bialgebra has a Hopf coreflection and on every algebra there exists a cofree Hopf algebra. In this way we give an affirmative answer to
Bao-Feng Feng, Ken-ichi Maruno, Yasuhiro Ohta
A self-adaptive moving mesh method is proposed for the numerical simulations of the Camassa-Holm equation. It is an integrable scheme in the sense that it possesses the exact N-soliton solution. It is named a self-adaptive moving mesh method, because the non-uniform mesh is driven and adapted automatically by the solution. Once the non-uniform mesh is evolve
Spin-Related Current Suppression in a Semiconductor-Quantum-Dot Spin-Diode Structure
cond-mat.mes-hallK. Hamaya, M. Kitabatake, K. Shibata, M. Jung
We experimentally study the transport features of electrons in a spin-diode structure consisting of a single semiconductor quantum dot (QD) weakly coupled to one nonmagnetic (NM) and one ferromagnetic (FM) lead, in which the QD has an artificial atomic nature. A Coulomb stability diamond shows asymmetric features with respect to the polarity of the bias volt
Frank Close, Clark Downum
Pion exchange in S-wave between hadrons that are themselves in a relative S-wave can shift energies by hundreds of MeV. In the case of charmed mesons $D,D^*,D_0,D_1$ a spectroscopy of quasi-molecular states may arise consistent with enigmatic charmonium states observed above 4 GeV in $e^+e^-$ annihilation. A possible explanation of $Y(4260)\to ψππ$ and $Y(43
Rong-Jia Yang, Shuang Nan Zhang
The age problem in the $Λ$CDM model is re-examined. We define the elapsed time $T$ of an object is its age plus the age of the Universe when it was born. Therefore in any cosmology, $T$ must be smaller than the age of the Universe. For the old quasar APM 08279+5255 at $z=3.91$, previous studies have determined the best-fit value of $T$, 1 $σ$ lower limit and
Elena Agliari, Raffaella Burioni
We study the random walk problem on a class of deterministic Scale-Free networks displaying a degree sequence for hubs scaling as a power law with an exponent $γ=\log 3/\log2$. We find exact results concerning different first-passage phenomena and, in particular, we calculate the probability of first return to the main hub. These results allow to derive the
De-Jun Feng, Wen Hunag
For general asymptotically sub-additive potentials (resp. asymptotically additive potentials) on general topological dynamical systems, we establish some variational relations between the topological entropy of the level sets of Lyapunov exponents, measure-theoretic entropies and topological pressures in this general situation. Most of our results are obtain
Da-Wei Pang
We investigate several aspects of exact black hole solutions in asymptotically Lifshitz spacetime, which were proposed in 0812.0530. Firstly, we calculate the tidal forces and find that in the near horizon region of such black hole backgrounds, the tidal forces diverge in the near extremal limit. Secondly, we evaluate the Wilson loops in both extremal and fi
Xian-Hui Ge, Sang-Jin Sin, Shao-Feng Wu, Guo-Hong Yang
We calculate the ratio of shear viscosity to entropy density for charged black branes in third order Lovelock theory. For chargeless black branes, the result turns out to be consistent with the prediction made in $\rm arXiv:0808.3498[\rm hep-th] $. We find that, the third order Lovelock gravity term does not contribute to causality violation unlike the Gauss
Manoj K. Yadav
Let $G$ be a finite group and $M(G)$ be the subgroup of $G$ generated by all non-central elements of $G$ that lie in the conjugacy classes of the smallest size. Recently several results have been proved regarding the nilpotency class of $M(G)$ and $F(M(G))$, where $F(M(G))$ denotes the Fitting subgroup of $M(G)$. We prove some conditional results regarding t
Fernando G. S. L. Brandao, Nilanjana Datta
We obtain expressions for the optimal rates of one- shot entanglement manipulation under operations which generate a negligible amount of entanglement. As the optimal rates for entanglement distillation and dilution in this paradigm, we obtain the max- and min-relative entropies of entanglement, the two logarithmic robustnesses of entanglement, and smoothed
R. N. Karasev
In this paper we prove that it is possible to inscribe a regular crosspolytope (multidimensional octahedron) into a smooth convex body in $\mathbb R^d$, where $d$ is an odd prime power. Some generalizations of this statement are also proved.
Robert J. Rutten
I first review trends in current solar spectrometry and then concentrate on comparing various spectroscopic diagnostics of the solar chromosphere. Some are actually not at all chromospheric but just photospheric or clapotispheric and do not convey information on chromospheric heating, even though this is often assumed. Balmer Halpha is the principal displaye
A Monte Carlo generator of nucleon configurations in complex nuclei including Nucleon-Nucleon correlations
nucl-thM. Alvioli, H. -J. Drescher, M. Strikman
We developed a Monte Carlo event generator for production of nucleon configurations in complex nuclei consistently including effects of Nucleon-Nucleon (NN) correlations. Our approach is based on the Metropolis search for configurations satisfying essential constraints imposed by short- and long-range NN correlations, guided by the findings of realistic calc
Zakirjon Kanokov, Juern W. P. Schmelzer, Avazbek K. Nasirov
The effect of ultralow-frequency or static magnetic and electric fields on biological processes is of huge interest for researchers due to the resonant change of the intensity of biochemical reactions although the energy in such fields is small. A simplified model to study the effect of the weak magnetic and electrical fields on fluctuation of the random ion
Timo Hanke, Jack Sonn
Since Amitsur's discovery of noncrossed product division algebras more than 35 years ago, their existence over more familiar fields has been an object of investigation. Brussel's work was a culmination of this effort, exhibiting noncrossed products over the rational function field k(t) and the Laurent series field k((t)) over any global field k -- th
Giovanni Petri, Henrik Jeldtoft Jensen, John W. Polak
A generic network flow model of transport (of relevance to information transport as well as physical transport) is studied under two different control protocols. The first involves information concerning the global state of the network, the second only information about nodes' nearest neighbors. The global protocol allows for a larger external drive befo
Hua-Wei Shen, Xue-Qi Cheng, Jia-Feng Guo
It has been shown that the communities of complex networks often overlap with each other. However, there is no effective method to quantify the overlapping community structure. In this paper, we propose a metric to address this problem. Instead of assuming that one node can only belong to one community, our metric assumes that a maximal clique only belongs t
H. Razmi, A. MohammadKazemi
The intrinsic angular momentum, or spin, is a cornerstone of modern physics with profound applications from nuclear magnetic resonance to spintronics. While its mathematical structure within quantum theory is well-defined, its fundamental origin is often less emphasized. This paper revisits the genesis of spin by examining its emergence in relativistic wave
M. Jaaskelainen, U. Zuelicke
We have obtained numerically exact results for the spin-related geometric quantum phases that arise in p-type semiconductor ring structures. The interplay between gate-controllable (Rashba) spin splitting and quantum-confinement-induced mixing between hole-spin states causes a much higher sensitivity of magnetoconductance oscillations to external parameters
Jacques Distler, Skip Garibaldi
We analyze certain subgroups of real and complex forms of the Lie group E8, and deduce that any "Theory of Everything" obtained by embedding the gauge groups of gravity and the Standard Model into a real or complex form of E8 lacks certain representation-theoretic properties required by physical reality. The arguments themselves amount to representat
Kamel Aouiche, Daniel Lemire, Robert Godin
Increasingly, business projects are ephemeral. New Business Intelligence tools must support ad-lib data sources and quick perusal. Meanwhile, tag clouds are a popular community-driven visualization technique. Hence, we investigate tag-cloud views with support for OLAP operations such as roll-ups, slices, dices, clustering, and drill-downs. As a case study, w
Immersivity of the contact line bundle of a complex-contact manifold and an application to the automorphism group
math.DGOsami Yasukura
A connected Fano complex-contact manifold is isomorphic to the kaehlerian C-space of Boothby type with a natural complex-contact structure corresponding to a non-abelian simple complex Lie algebra if the contact line bundle is very ample. A. Beauville relaxed the provision to two assumptions that the contact line bundle is generically finite and that the aut
Joohan Lee, Tae Hoon Lee, Taeyoon Moon, Phillial Oh
We consider a cosmology with a non-compact nonlinear sigma model.The target space is of de-Sitter type and four scalar fields are introduced.The potential is absent but cosmological constant term $Λ$ is added. One of the scalar fields is time dependent and the remaining three fields have no time dependence but only spatial dependence. We show that a very sim
Jacob Fox, Benny Sudakov
The Gallai-Milgram theorem says that the vertex set of any digraph with stability number k can be partitioned into k directed paths. In 1990, Hahn and Jackson conjectured that this theorem is best possible in the following strong sense. For each positive integer k, there is a digraph D with stability number k such that deleting the vertices of any k-1 direct
David Fisher, Boris Kalinin, Ralf Spatzier
We show that sufficiently irreducible totally non-symplectic Anosov actions of higher rank abelian groups on tori and nilmanifolds are smoothly conjugate to affine actions.
Disorder effect on the spin susceptibility of the two-dimensional one-valley electron gas
cond-mat.str-elS De Palo, S Moroni, G Senatore
Starting from the quantum Monte Carlo (QMC) prediction for the ground-state energy of a clean two-dimensional one-valley (2D1V) electron gas, we estimate the energy correction due to scattering sources present in actual devices such as AlAs quantum wells and GaAs heterostructures. We find that the effect of uncorrelated disorder, in the lowest (second) order
Thomas Chen, Nataša Pavlović, Nikolaos Tzirakis
We consider solutions of the focusing cubic and quintic Gross-Pitaevskii (GP) hierarchies. We identify an observable corresponding to the average energy per particle, and we prove that it is a conserved quantity. We prove that all solutions to the focusing GP hierarchy at the $L^2$-critical or $L^2$-supercritical level blow up in finite time if the energy pe
Victor Gryaznov, Igor Iosilevski, Eugene Yakub, Vladimir Fortov
The paper presents a model for liquid uranium dioxide, obtained by improving a simplified ionic model, previously adopted to describe the equation of state of this substance [1]. A "chemical picture" is used for liquid UO2 of stoichiometric and non-stoichiometric composition. Several ionic species are considered here: U(5+), U(4+), U(3+), O(2-) and O
M. R. Dietrich, A. Avril, R. Bowler, N. Kurz
Individually trapped 137Ba+ in an RF Paul trap is proposed as a qubit ca ndidate, and its various benefits are compared to other ionic qubits. We report the current experimental status of using this ion for quantum computation. Fut ure plans and prospects are discussed.
The Araucaria Project. The Distance to the Sculptor Galaxy NGC 247 from Near-Infrared Photometry of Cepheid Variables
astro-ph.COW. Gieren, G. Pietrzynski, I. Soszynski, O. Szewczyk
We have obtained deep near-infrared images in J and K filters of four fields in the Sculptor Group spiral galaxy NGC 247 with the ESO VLT and ISAAC camera. For a sample of ten Cepheids in these fields, previously discovered by Garc{í}a-Varela et al. from optical wide-field images, we have determined mean J and K magnitudes and have constructed the period-lum
Raluca Balan
In this article, we establish a probabilistic representation for the second-order moment of the solution of stochastic heat equation in $[0,1] \times \bR^d$, with multiplicative noise, which is fractional in time and colored in space. This representation is similar to the one given in Dalang, Mueller and Tribe (2008) in the case of an s.p.d.e. driven by a Ga
J. F. Cariñena, Miguel Rodriguez-Olmos
We develop a theory of gauge and dynamical equivalence for Lagrangian systems on Lie algebroids, also studying its relationship with Noether and non-Noether conserved quantities.
Jonathan P. Hall, Stephen F. King
We discuss neutralino dark matter arising from supersymmetric models with extra inert Higgsinos and singlinos, where inert means that their scalar partners do not get vacuum expectation values. As an example, we consider the extended neutralino sector of the E$_6$SSM, which predicts three families of Higgs doublet pairs, plus three singlets, plus a $Z'$,
Hydrodynamical simulations of convection-related stellar micro-variability. II. The enigmatic granulation background of the COROT target HD49933
astro-ph.SRH. -G. Ludwig, R. Samadi, M. Steffen, T. Appourchaux
Local-box hydrodynamical model atmospheres provide statistical information about a star's emergent radiation field which allows one to predict the level of its granulation-related micro-variability. Space-based photometry is now sufficiently accurate to test model predictions. We aim to model the photometric granulation background of HD49933 as well as t
M. C. Davis, R Carretero-González, Z. Shi, K. J. H. Law
We consider the manipulation of Bose-Einstein condensate vortices by optical potentials generated by focused laser beams. It is shown that for appropriate choices of the laser strength and width it is possible to successfully transport vortices to various positions inside the trap confining the condensate atoms. Furthermore, the full bifurcation structure of
Rolando Magnanini, Giorgio Talenti
Theories of monochromatic high-frequency electromagnetic fields have been designed by Felsen, Kravtsov, Ludwig and others with a view to portraying features that are ignored by geometrical optics. These theories have recourse to eikonals that encode information on both phase and amplitude -- in other words, are complex-valued. The following mathematical prin
Optical spectra obtained from amorphous films of rubrene: Evidence for predominance of twisted isomer
cond-mat.softM. Kytka, L. Gisslen, A. Gerlach, U. Heinemeyer
In order to investigate the optical properties of rubrene we study the vibronic progression of the first absorption band (lowest π-> π^* transition). We analyze the dielectric function of rubrene in solution and thin films using the displaced harmonic oscillator model and derive all relevant parameters of the vibronic progression. The findings are supplement
Ya. I. Rodionov, I. S. Burmistrov, A. S. Ioselevich
We study the dissipation in a system consisting of a small metallic island coupled to a gate electrode and to a massive reservoir via single tunneling junction. The dissipation of energy is caused by a slowly oscillating gate voltage. We compute it in the regimes of weak and strong Coulomb blockade. We focus on the regime of not very low temperatures when el
Theoretical Study of Atomic Structure and Elastic Properties of Branched Silicon Nanowires
cond-mat.mes-hallPavel B. Sorokin, Alexander G. Kvashnin, Dmitry G. Kvashnin, Pavel V. Avramov
The atomic structure and elastic properties of Y-silicon nanowire junctions of fork- and bough-types were theoretically studied and effective Young modulus were calculated using the Tersoff interatomic potential. In the final stages of bending, new bonds between different parts of the Y-shaped wires are formed. It was found that the stiffness of the nanowire
Local-moment ferromagnetism and unusual magnetic domains in Fe$_{1/4}$TaS$_{2}$ crystals
cond-mat.str-elM. D. Vannette, S. Yeninas, E. Morosan, R. J. Cava
Single crystals of Fe$_{1/4}$TaS$_{2}$ have been studied by using magneto-optical (MO) imaging and radio-frequency (rf) magnetic susceptibility, $χ$. Real time MO images reveal unusual, slow dynamics of dendritic domain formation, the details of which are strongly dependent upon magnetic and thermal history. Measurements of $χ(T)$ show well-defined, local mo
Majid Jahangiri
Let $p$ be a prime and $a$ a quadratic non-residue $\bmod p$. Then the set of integral solutions of the diophantine equation $x_0^2 - ax_1^2 -px_2^2 + apx_3^2=1$ form a cocompact discrete subgroup $Γ_{p,a}\subset SL(2,\mathbb{R})$ and is commensurable with the group of units of an order in a quaternion algebra over $\mathbb{Q}$. The problem addressed in this
Strong electron-electron correlation and weak localization in CeO_{0.9}F_{0.1}Fe_{1-x}Co_xAs
cond-mat.supr-conS. J. Singh, J. Prakash, S. Patnaik, A. K. Ganguli
Electron-doping of the semimetal (CeOFeAs) by either fluorine (max Tc ~ 43 K)or cobalt (max Tc ~ 11 K) leads to superconductivity. Here we show the effect of transition metal (Co) substitution at the iron site on the superconducting properties of CeO0.9F0.1FeAs (Tc ~38 K)to understand the interplay of charge carriers in both the rare earth-oxygen and Fe-As l
G. Botelho, D. Diniz, D. Pellegrino, E. Teixeira
In this note we answer a question concerning lineability of the set of non-absolutely summing operators.
Samir M. Perlaza, Merouane Debbah, Samson Lasaulce, Hanna Bogucka
We study the network spectral efficiency of decentralized vector multiple access channels (MACs) when the number of accessible dimensions per transmitter is strategically limited. Considering each dimension as a frequency band, we call this limiting process bandwidth limiting (BL). Assuming that each transmitter maximizes its own data rate by water-filling o
F. W. S. Lima, Tarik Hadzibeganovic, Dietrich Stauffer
Using Monte Carlo simulations, we study the evolution of contigent cooperation and ethnocentrism in the one-move game. Interactions and reproduction among computational agents are simulated on {\it undirected} and {\it directed} Barabási-Albert (BA) networks. We first replicate the Hammond-Axelrod model of in-group favoritism on a square lattice and then gen
Jaap van Oosten
We employ the notions of `sequential function' and `interrogation' (dialogue) in order to define new partial combinatory algebra structures on sets of functions. These structures are analyzed using J. Longley's preorder-enriched category of partial combinatory algebras and decidable applicative structures. We also investigate total combinatory al
M. Sharif, G. Abbas
In this paper, the effect of electromagnetic field has been investigated on the spherically symmetric collapse with the perfect fluid in the presence of positive cosmological constant. Junction conditions between the static exterior and non-static interior spherically symmetric spacetimes are discussed. We study the apparent horizons and their physical signi
M. Sharif, Sajid Sultan
This paper is devoted to explore tilted kinematic self-similar solutions of the the general cylindrical symmetric spacetimes. These solutions are of the first, zeroth, second and infinite kinds for the perfect fluid and dust cases. Three different equations of state are used to obtain these solutions. We obtain a total of five independent solutions. The corr
Multi-frequency measurements of the NVSS foreground sources in the Cosmic Background Imager fields. I. Data release
astro-ph.COE. Angelakis, A. Kraus, A. C. S. Readhead, J. A. Zensus
We present the results of the flux density measurements at 4.85 GHz and 10.45 GHz of a sample of 5998 NVSS radio sources with the Effelsberg 100 m telescope. The initial motivation was the need to identify the NVSS radio sources that could potentially contribute significant contaminating flux in the frequency range at which the Cosmic Background Imager exper
Walid Saad, Zhu Han, Merouane Debbah, Are Hjørungnes
Collaborative spectrum sensing among secondary users (SUs) in cognitive networks is shown to yield a significant performance improvement. However, there exists an inherent trade off between the gains in terms of probability of detection of the primary user (PU) and the costs in terms of false alarm probability. In this paper, we study the impact of this trad
Juan Li, Zhi-Qiang Shen, Atsushi Miyazaki, Lei Huang
We have performed monitoring observations of the 3-mm flux density toward the Galactic Center compact radio source Sgr A* with the Australia Telescope Compact Array since 2005 October. Careful calibrations of both elevation-dependent and time-dependent gains have enabled us to establish the variability behavior of Sgr A*. Sgr A* appeared to undergo a high an
D. J. E. Floyd, N. F. Bate, R. L. Webster
We present single-epoch multi-wavelength optical-NIR observations of the "anomalous" lensed quasar SDSS J0924+0219, made using the Magellan 6.5-metre Baade telescope at Las Campanas Observatory, Chile. The data clearly resolve the anomalous bright image pair in the lensed system, and exhibit a strong decrease in the anomalous flux ratio with decreasing wavel
T. Kyle Petersen, Luis Serrano
We show that the set R(w_0) of reduced expressions for the longest element in the hyperoctahedral group exhibits the cyclic sieving phenomenon. More specifically, R(w_0) possesses a natural cyclic action given by moving the first letter of a word to the end, and we show that the orbit structure of this action is encoded by the generating function for the maj
Soumya Banerjee
An immune system inspired Artificial Immune System (AIS) algorithm is presented, and is used for the purposes of automated program verification. Relevant immunological concepts are discussed and the field of AIS is briefly reviewed. It is proposed to use this AIS algorithm for a specific automated program verification task: that of predicting shape of progra
Li-yun Hu, Xue-xiang, Hong-yi Fan
We investigate the statistical properties of the photon-subtractions from the two-mode squeezed vacuum state and its decoherence in a thermal environment. It is found that the state can be considered as a squeezed two-variable Hermite polynomial excitation vacuum and the normalization of this state is the Jacobi polynomial of the squeezing parameter. The com
Christian Buth, Kenneth J. Schafer
Using attoscience, we study the electron correlations responsible for Auger decay in krypton atoms. The Auger decay is induced by a pulse train or a twin pulse composed of subpulses of attosecond duration. During the Auger decay an optical dressing laser may be present. Interference effects between the ejected Auger electron wave packets are predicted.
Xiang He, Aylin Yener
Recent results have shown that lattice codes can be used to construct good channel codes, source codes and physical layer network codes for Gaussian channels. On the other hand, for Gaussian channels with secrecy constraints, efforts to date rely on random codes. In this work, we provide a tool to bridge these two areas so that the secrecy rate can be comput
Xiang He, Aylin Yener
In this work, we consider achievable secrecy rates for symmetric $K$-user ($K \ge 3$) interference channels with confidential messages. We find that nested lattice codes and layered coding are useful in providing secrecy for these channels. Achievable secrecy rates are derived for very strong interference. In addition, we derive the secure degrees of freedom
Matthew M. Glenz
In this dissertation, we introduce a general way of modeling inflation in a framework that is independent of the exact nature of the inflationary potential. Because of the choice of our initial conditions and the continuity of the scale factor in its first two derivatives, we obtain non-divergent results without the need for any renormalization beyond what i
Xiang He, Aylin Yener
We investigate the $K$-user many-to-one interference channel with confidential messages in which the $K$th user experiences interference from all other $K-1$ users, and is at the same time treated as an eavesdropper to all the messages of these users. We derive achievable rates and an upper bound on the sum rate for this channel and show that the gap between
Narayana Santhanam, Martin J. Wainwright
The problem of graphical model selection is to correctly estimate the graph structure of a Markov random field given samples from the underlying distribution. We analyze the information-theoretic limitations of the problem of graph selection for binary Markov random fields under high-dimensional scaling, in which the graph size $p$ and the number of edges $k
Tian De Cao, Tie Bang Wang
The competition between singlet and triplet superconductivity is examined in consideration of correlations on an extended Hubbard model. It is shown that the triplet superconductivity may not be included in the common Hubbard model since the strong correlation favors the singlet superconductivity, and thus the triplet superconductivity should be induced by t
Krzysztof Bogdan, Tomasz Grzywny, Michał Ryznar
We give sharp estimates for the heat kernel of the fractional Laplacian with Dirichlet condition for a general class of domains including Lipschitz domains.
Hubert L. Bray, Marcus A. Khuri
In this paper, we show how to reduce the Penrose conjecture to the known Riemannian Penrose inequality case whenever certain geometrically motivated systems of equations can be solved. Whether or not these special systems of equations have general existence theories is therefore an important open problem. The key tool in our method is the derivation of a new
Sergey A. Antonyan
Let X be a Hausdorff topological group and G a locally compact subgroup of X. We show that the natural action of G on X is proper in the sense of R. Palais. This is applied to prove that there exists a closed set F of X such that FG=X and the restriction of the quotient projection X -> X/G to F is a perfect map F -> X/G. This is a key result to prove that ma
The effect of baryons on the variance and the skewness of the mass distribution in the universe at small scales
astro-ph.COT. Guillet, R. Teyssier, S. Colombi
We study the dissipative effects of baryon physics on cosmic statistics at small scales using a cosmological simulation of a (50 Mpc/h)^3 volume of the universe. The MareNostrum simulation was performed using the AMR code RAMSES, and includes most of the physical ingredients which are part of the current theory of galaxy formation, such as metal-dependent co
Jakob Palmkvist
The three-algebras used by Bagger and Lambert in N=6 theories of ABJM type are in one-to-one correspondence with a certain type of Lie superalgebras. We show that the description of three-algebras as generalized Jordan triple systems naturally leads to this correspondence. Furthermore, we show that simple three-algebras correspond to simple Lie superalgebras
A. N. Sergeev, A. P. Veselov
We prove that Euler supercharacters for orthosymplectic Lie superalgebras can be obtained as a certain specialization of super Jacobi polynomials. A new version of Weyl type formula for super Schur functions and specialized super Jacobi polynomials play a key role in the proof.
A. N. Sergeev, A. P. Veselov
Jacobi-Trudy formula for a generalisation of Schur polynomials related to any sequence of orthogonal polynomials in one variable is given. As a corollary we have Giambelli formula for generalised Schur polynomials.
Justin Lovegrove
Autocorrelation analyses of the optical continua of 57 of the 59 MACHO quasars reveal structure at proper time lags of 544 +- 5.2 days with a standard deviation of 77 light days. Interpreted in the context of reverberation from elliptical outflow winds as proposed by Elvis (2000) [1], this implies an approximate characteristic size scale for winds in the MAC
Tom Kennedy
Real space renormalization group maps, e.g., the majority rule transformation, map Ising type models to Ising type models on a coarser lattice. We show that each coefficient of the renormalized Hamiltonian in the lattice gas variables depends on only a finite number of values of the renormalized Hamiltonian. We introduce a method which computes the values of
Y. -J. Han, Y. -H. Chan, W. Yi, A. J. Daley
It is hard to stabilize the p-wave superfluid state of cold atomic gas in free space due to inelastic collisional losses. We consider the p-wave Feshbach resonance in an optical lattice, and show that it is possible to have a stable p-wave superfluid state where the multi-atom collisional loss is suppressed through the quantum Zeno effect. We derive the effe
Samson Saneblidze
Let $A$ be a special homotopy G-algebra over a commutative unital ring $\Bbbk$ such that both $H(A)$ and $\operatorname{Tor}_{i}^{A}(\Bbbk,\Bbbk)$ are finitely generated $\Bbbk$-modules for all $i$, and let $τ_{i}(A)$ be the cardinality of a minimal generating set for the $\Bbbk$-module $\operatorname{Tor}_{i}^{A}(\Bbbk,\Bbbk).$ Then the set ${τ_{i}(A)} $ is
Patrick Delorme
We define the Fourier transform of compactly supported Whittaker functions on a reductive p-adic group and we characterize the image of this transformation.
A. V. Gulov, V. V. Skalozub
An approach to the model-independent searching for the Z' gauge boson as a virtual state in scattering processes is developed. It accounts for as a basic requirement the renormalizability of underlying unspecified in other respects model. This results in a set of relations between low energy couplings of Z' to fermions that reduces in an essential wa
Emily B. Fox, Erik B. Sudderth, Michael I. Jordan, Alan S. Willsky
We consider the problem of speaker diarization, the problem of segmenting an audio recording of a meeting into temporal segments corresponding to individual speakers. The problem is rendered particularly difficult by the fact that we are not allowed to assume knowledge of the number of people participating in the meeting. To address this problem, we take a B
Jason Bell, Stanley Burris, Karen Yeats
Characteristic points have been a primary tool in the study of a generating function defined by a single recursive equation. We investigate the proper way to adapt this tool when working with multi-equation recursive systems.
A. Esquivel, A. Lazarian
We used magnetohydrodynamic (MHD) simulations of interstellar turbulence to study the probability distribution functions (PDFs) of increments of density, velocity, and magnetic field. We found that the PDFs are well described by a Tsallis distribution, following the same general trends found in solar wind and Electron MHD studies. We found that the PDFs of d
The contribution of the kinematic Sunyaev-Zel'dovich Effect from the Warm Hot Intergalactic Medium to the Five-Year WMAP Data
astro-ph.CORicardo Genova-Santos, Fernando Atrio-Barandela, Jan Muecket, Jochen Klar
We study the contribution of the kinematic Sunyaev-Zel'dovich (kSZ) effect, generated by the warm-hot intergalactic medium (WHIM), to the cosmic microwave background (CMB) temperature anisotropies in the Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) data. We explore the concordance LambdaCDM cosmological model, with and without this kSZ contribut