March 2010 arXiv papers — page 43

Jesús Guillera

Our main results are a WZ-proof of a new Ramanujan-like series for $1/π^2$ and a hypergeometric identity involving three series.

Prateek Agrawal, Zackaria Chacko, Can Kilic, Rashmish K. Mishra

We perform a model-independent classification of Weakly Interacting Massive Particle (WIMP) dark matter candidates that have the property that their scattering off nucleons is dominated by spin-dependent interactions. We study renormalizable theories where the scattering of dark matter is elastic and arises at tree-level. We show that if the WIMP-nucleon cro

Luka Grubisic, Vadim Kostrykin, Konstantin A. Makarov, Kresimir Veselic

The first and second representation theorems for sign-indefinite, not necessarily semi-bounded quadratic forms are revisited. New straightforward proofs of these theorems are given. A number of necessary and sufficient conditions ensuring the second representation theorem to hold is proved. A new simple and explicit example of a self-adjoint operator for whi

E. Brussel, E. Tengan

Let F be a field of transcendence degree one over a p-adic field, and let l be a prime not equal to p. Results of Merkurjev and Saltman show that H^2(F,μ_l) is generated by Z/l-cyclic classes. We prove the "Z/l-length" in H^2(F,μ_l) equals the l-Brauer dimension, which Saltman showed to be two. It follows that all F-division algebras of period l are

David J. Green, László Héthelyi, Nadia Mazza

We introduce a strong form of Oliver's p-group conjecture and derive a reformulation in terms of the modular representation theory of a quotient group. The Sylow p-subgroups of the symmetric group S_n and of the general linear group GL_n(F_q) satisfy both the strong conjecture and its reformulation.

Charles P. Boyer

I describe a general scheme which associates conjugacy classes of tori in the contactomorphism group to transverse almost complex structures on a compact contact manifold. Moreover, to tori of Reeb type whose Lie algebra contains a Reeb vector field one can associate a Sasaki cone. Thus, for contact structures of K-contact type one obtains a configuration of

Qing Ai, Yong Li, Hang Zheng, C. P. Sun

In this paper, we systematically study the spontaneous decay phenomenon of a two-level system under the influences of both its environment and continuous measurements. In order to clarify some well-established conclusions about the quantum Zeno effect (QZE) and the quantum anti-Zeno effect (QAZE), we do not use the rotating wave approximation (RWA) in obtain

Ada Ortiz, Luis R. Bellot Rubio, Luc Rouppe van der Voort

We study the velocity field of umbral dots at a resolution of 0.14". Our analysis is based on full Stokes spectropolarimetric measurements of a pore taken with the CRISP instrument at the Swedish 1-m Solar Telescope. We determine the flow velocity at different heights in the photosphere from a bisector analysis of the Fe I 630 nm lines. In addtion, we us

K. Karami, Mubasher Jamil, N. Sahraei

We study the irreversible (non-equilibrium) thermodynamics of FRW universe containing only dark energy. Using the modified entropy-area relation which is motivated from the loop quantum gravity, we calculate the entropy-corrected form of the apparent horizon of FRW universe.

Olivier Minazzoli, Bertrand Chauvineau

The metric recommanded by the IAU2000 resolutions allows propagation of light calculations at the c-3 level in the general relativity framework. In a recent paper [1], motivated by forthcoming space experiments involving propagation of light in the Solar System (ASTROD, GAIA, LATOR, ODYSSEY, SAGAS, SIM, TIPO, ...), we have proposed an extention of the IAU me

Tom Alberts, Kostya Khanin, Jeremy Quastel

We introduce a new disorder regime for directed polymers with one space and one time dimension that is accessed by scaling the inverse temperature parameter βwith the length of the polymer n. We scale β_n := βn^{-α} for alpha non-negative. This scaling sits in between the usual weak disorder (β= 0) and strong disorder regimes (β> 0). The fluctuation exponent

Morten Vierling

We consider the variational discretization of a linear-quadratic optimal control problem with pointwise control and state constraints. In order to allow for a Fréchet smooth norm, the problem is reformulated by means of a reflexive Sobolev space instead of the space of continuous functions. The discretization of the state equation yields a family of perturbe

Vinko Zlatić, Andrea Gabrielli, Guido Caldarelli

We present a new approach of topology biased random walks for undirected networks. We focus on a one parameter family of biases and by using a formal analogy with perturbation theory in quantum mechanics we investigate the features of biased random walks. This analogy is extended through the use of parametric equations of motion (PEM) to study the features o

Aristeu R. P. Lima, Axel Pelster

The quest for quantum degenerate Fermi gases interacting through the anisotropic and long-range dipole-dipole interaction is an exciting and fast developing branch within the cold-atoms research program. Recent experimental progress in trapping, cooling, and controlling polar molecules with large electric dipole moments has, therefore, motivated much theoret

Gennadi Henkin, Matteo Santacesaria

Let $\hat Ω\subset \mathbb R^2$ be a bounded domain with smooth boundary and $\hat σ$ a smooth anisotropic conductivity on $\hat Ω$. Starting from the Dirichlet-to-Neumann operator $Λ_{\hat σ}$ on $\partial \hat Ω$, we give an explicit procedure to find a unique domain $Ω$, an isotropic conductivity $σ$ on $Ω$ and the boundary values of a quasiconformal diff

Jae-Weon Lee

It is shown that the first law of thermodynamics and the holographic principle applied to an arbitrary large cosmic causal horizon naturally demand the zero cosmological constant and non-zero dynamical dark energy in the form of the holographic dark energy. Semiclassical analysis shows that the holographic dark energy has a parameter $d=1$ and an equation of

Markus Kunze, Jan van Neerven

We investigate, in the setting of UMD Banach spaces E, the continuous dependence on the data A, F, G and X_0 of mild solutions of semilinear stochastic evolution equations with multiplicative noise of the form dX(t) = [AX(t) + F(t,X(t))]dt + G(t,X(t))dW_H(t), X(0)=X_0, where W_H is a cylindrical Brownian motion on a Hilbert space H. We prove continuous depen

Nicolai Friis

One of the most fundamental phenomena of quantum physics is entanglement. It describes an inseparable connection between quantum systems, and properties thereof. In a quantum mechanical description even systems far apart from each other can share a common state. This entanglement of the subsystems, although arising from mathematical principles, is no mere ab

A. F. Volkov, K. B. Efetov

We study the dc Josephson effect in a diffusive multilayered SF'FF'S structure, where S is a superconductor and F,F' are different ferromagnets. We assume that the exchange energies in the F' and F layers are different ($% h $ and $H$, respectively) and the middle F layer consists of two layers with parallel or antiparallel magnetization vect

Marc H. E. de Lussanet, Jan W. M. Osse

Among the best-known facts of the brain are the contralateral visual, auditory, sensational, and motor mappings in the forebrain. How and why did these evolve? The few theories to this question provide functional answers, such as better networks for visuomotor control. However, these theories contradict the data, as discussed here. Instead we propose that a

Alexander Stolin

The aim of the present paper is to establish relations between Iwasawa and Bernoulli numbers based on some results by M. Kervaire and M. P. Murthy about the structure of the $K_0$ groups of the integer group rings of cyclic groups of prime power order $p^n .$ In particular, we will prove that $\lambda_{i}\leq p-1$ under assumption that the generalized Bernou

Jian-Li Li, Jian-Pin Wu

The dynamics of a tachyon field plus a barotropic fluid is investigated in spatially curved FRW universe. We perform a phase-plane analysis and obtain scaling solutions accompanying with a discussion on their stability. Furthermore, we construct the form of scalar potential which may give rise to stable solutions for spatially open and closed universe separa

Peter Kopietz, Lorenz Bartosch, Lucio Costa, Aldo Isidori

Using functional methods and the exact renormalization group we derive Ward identities for the Anderson impurity model. In particular, we present a non-perturbative proof of the Yamada-Yosida identities relating certain coefficients in the low-energy expansion of the self-energy to thermodynamic particle number and spin susceptibilities of the impurity. Our

Cristiana Bertolin

Let S be a site. We introduce the notion of extensions of strictly commutative Picard S-stacks. We define the pull-back, the push-down, and the sum of such extensions and we compute their homological interpretation: if P and Q are two strictly commutative Picard S-stacks, the equivalence classes of extensions of P by Q are parametrized by the cohomology grou

Tae Hoon Lee

In Horava's theory of gravity coupled to a global monopole source, we seek for static, spherically symmetric spacetime solutions for general values of $λ$. We obtain the explicit solutions with deficit solid angles, in the IR modified Horava gravity model, at the IR fixed point $λ=1$ and at the conformal point $λ=1/3$. For the other values of $1>λ>0$ we

Nicolas Destainville, Bertrand Georgeot, Olivier Giraud

We build a quantum algorithm which uses the Grover quantum search procedure in order to sample the exact equilibrium distribution of a wide range of classical statistical mechanics systems. The algorithm is based on recently developed exact Monte Carlo sampling methods, and yields a polynomial gain compared to classical procedures.

T. Chwiej, K. Kutorasinski

We theoretically study the single electron transfer through two-terminal quantum ring capacitively coupled to charged dot placed in its center. For this purpose we solve time-dependent Schrodinger equation for fully correlated two-particle system constituted by the transferred electron and the second particle confined in the dot. Analysis of transmission pro

Niels Warburton, Leor Barack

We present a calculation of the scalar field self-force (SSF) acting on a scalar-charge particle in a strong-field orbit around a Kerr black hole. Our calculation specializes to circular and equatorial geodesic orbits. The analysis is an implementation of the standard mode-sum regularization scheme: We first calculate the multipole modes of the scalar-field

Jayme De Luca

The equations for the electromagnetic two-body problem are neutral-delay equations that for generic initial data have solutions with discontinuous derivatives. If one wants to use these neutral-delay equations with arbitrary initial data, solutions with discontinuous derivatives must be allowed. Surprisingly, this same neutrality is compatible with the recen

S. Albino, B. A. Kniehl, G. Kramer

We compare the transverse momentum (p_T) distribution of inclusive light-charged-particle production measured by the CDF Collaboration at the Fermilab Tevatron with the theoretical prediction evaluated at next-to-leading order in quantum chromodynamics (QCD) using fragmentation functions recently determined through a global data fit. While, in the lower p_T

Jesse Alt

We apply the theory of Weyl structures for parabolic geometries developed by A. Cap and J. Slovak in to compute, for a quaternionic contact (qc) structure, the Weyl connection associated to a choice of scale, i.e. to a choice of Carnot-Carathéodory metric in the conformal class. The result of this computation has applications to the study of the conformal Fe

Abhiram Soori, Diptiman Sen

We study charge pumping when a combination of static potentials and potentials oscillating with a time period T is applied in a one-dimensional system of non-interacting electrons. We consider both an infinite system using the Dirac equation in the continuum approximation, and a periodic ring with a finite number of sites using the tight-binding model. The i

Anton Deitmar

We present the theory of higher order invariants and higher order automorphic forms in the simplest case, that of a compact quotient. In this case many things simplify and we are thus able to prove a more precise structure theorem than in the general case.

James W. Anderson, Cyril Lecuire

In this paper we give a complete description of the set of discrete faithful representations SH(M) uniformizing a compact, orientable, hyperbolizable 3-manifold M with incompressible boundary, equipped with the strong topology, with the description given in term of the end invariants of the quotient manifolds. As part of this description, we introduce coordi

Kai Zehmisch

We show that any simple holomorphic disc admits the annulus property, i.e., each interior point is surrounded by an arbitrary small annulus consisting entirely of injective points. As an application we show that interior singularities of holomorphic discs can be resolved after slight perturbation of the almost complex structure. Moreover, for boundary points

Yang Xiang, Shi-Jie Xiong

On the basis of local realism theory, nonlocal information is necessary for violation of Bell's inequality. From a theoretical point of view, nonlocal information is essentially the mutual information on distant outcome and measurement setting. In this work we prove that if the measurement is free and unbiased, the mutual information about the distant ou

Amitai Regev

Closed formulas are known for $S(k,0;n)$, the number of standard Young tableaux of size $n$ and with at most $k$ parts, where $1\le k\le 5$. Here we study the analogue problem for $S(k,\ell;n)$, the number of standard Young tableaux of size $n$ which are contained in the $(k,\ell)$ hook. We deduce some formulas for the cases $k+\ell\le 4$.

Nikolay A. Gromov

The modification of the Electroweak Model with 3-dimensional spherical geometry in the matter fields space is suggested. The Lagrangian of this model is given by the sum of the {\it free} (without any potential term) matter fields Lagrangian and the standard gauge fields Lagrangian. The vector boson masses are generated by transformation of this Lagrangian f

Xuan Thinh Duong, Adam Sikora, Lixin Yan

Let $L$ be a non-negative self adjoint operator acting on $L^2(X)$ where $X$ is a space of homogeneous type. Assume that $L$ generates a holomorphic semigroup $e^{-tL}$ whose kernels $p_t(x,y)$ have Gaussian upper bounds but possess no regularity in variables $x$ and $y$. In this article, we study weighted $L^p$-norm inequalities for spectral multipliers of

Vidhi Rawat, Alok Jain, Vibhakar Shrimali

Digital image plays a vital role in the early detection of cancers, such as prostate cancer, breast cancer, lungs cancer, cervical cancer. Ultrasound imaging method is also suitable for early detection of the abnormality of fetus. The accurate detection of region of interest in ultrasound image is crucial. Since the result of reflection, refraction and defle

C. Peralta, L. Rosales, B. Rodrí guez-Mueller, W. Barreto

We apply the post-quasi--static approximation, an iterative method for the evolution of self-gravitating spheres of matter, to study the evolution of anisotropic non-adiabatic radiating and dissipative distributions in General Relativity. Dissipation is described by viscosity and free-streaming radiation, assuming an equation of state to model anisotropy ind

Ugo Bruzzo, Vladimir Rubtsov

We introduce the notion of skew-holomorphic Lie algebroid on a complex manifold, and explore some cohomologies theories that one can associate to it. Examples are given in terms of holomorphic Poisson structures of various sorts.

Keisuke Fujii, Katsuji Yamamoto

We demonstrate that repeated measurements in disordered systems can induce quantum anti-Zeno effect under certain condition to enhance quantum transport. The enhancement of energy transfer is really exhibited with a simple model under repeated measurements. The optimal measurement interval for the anti-Zeno effect and the maximal efficiency of energy transfe

Bo Hou, Shilin Yang

Suppose that $Q$ is a finite quiver and $G\subseteq \Aut(Q)$ is a finite group, $k$ is an algebraic closed field whose characteristic does not divide the order of $G$. For any algebra $Λ=kQ/{\mathcal {I}}$, $\mathcal {I}$ is an arbitrary ideal of path algebra $kQ$, we give all the indecomposable $ΛG$-modules from indecomposable $Λ$-modules when $G$ is abelia

D. J. Kedziora, C. Simenel

Based on time-dependent Hartree-Fock theory, a new inverse quasifission mechanism is proposed to produce neutron-rich transfermium nuclei, in collision of prolate deformed actinides. Calculations show that collision of the tip of one nucleus with the side of the other results in a nucleon flux toward the latter. The role of nucleon evaporation and impact par

Eitaro Shioji, Ryutaroh Matsumoto, Tomohiko Uyematsu

Silva et al. proposed a universal secure network coding scheme based on MRD codes, which can be applied to any underlying network code. This paper considers a stronger eavesdropping model where the eavesdroppers possess the ability to re-select the tapping links during the transmission. We give a proof for the impossibility of attaining universal security ag

Alexander S. Belyaev, R. Sekhar Chivukula, Neil D. Christensen, Hong-Jian He

The three site Higgsless model has been offered as a benchmark for studying the collider phenomenology of Higgsless models. In this talk, we present how well the three site Higgsless model performs as a general representative of Higgsless models in describing W_L W_L scattering, and which modifications can make it more representative. We employ general sum r

Tao Li, Qiang Han

We study the effect of thermal phase fluctuation on the electron spectral function $A(k,\omega)$ in a d-wave superconductor with Monte Carlo simulation. The phase degree of freedom is modeled by a XY-type model with build-in d-wave character. We find a ridge-like structure emerges abruptly on the underlying Fermi surface in $A(k,\omega=0)$ above the KT-trans

Atsushi Moriwaki

This paper is an enhancement of the previous note "Explicit computations of Zariski decompositions on P_Z^1". In this paper, we observe several properties of a certain kind of an arithmetic divisor D on the n-dimensional projective space over Z and give the exact form of the Zariski decomposition of D on the projective line over Z. Further, we show t

Alexander F. Ritter

We construct the TQFT on symplectic cohomology and wrapped Floer cohomology, possibly twisted by a local system of coefficients, and prove that the TQFT respects Viterbo restriction maps and the canonical maps from ordinary cohomology. We also construct the module structure of wrapped Floer cohomology over symplectic cohomology. These constructions yield new

Brian C. Lemaux, Lori M. Lubin, Alice E. Shapley, Dale D. Kocevski

We present the first results from a near-IR spectroscopic campaign of the Cl1604 supercluster at z~0.9 and the cluster RX J1821.6+6827 at z~0.82 to investigate the nature of [OII] 3727A emission in cluster galaxies at high redshift. Of the 401 members in the two systems, 131 galaxies have detectable [OII] emission with no other signs of current star-formatio

Takashi Hiramatsu, Masahiro Kawasaki, Fuminobu Takahashi

We study Q-ball formation in the expanding universe on 1D, 2D and 3D lattice simulations. We obtain detailed Q-ball charge distributions, and find that the distribution is peaked at Q^{3D}_{peak} \simeq 1.9\times 10^{-2} (|Φ_{in}|/m)^2, which is greater than the existing result by about 60%. Based on the numerical simulations, we discuss how the Q-ball forma

Li-Mei Wang

This survey mainly deals with the tilted Carath{é}odory class by angle $λ$ (denoted by $\mathcal{P}_λ$) an element of which maps the unit disc into the tilted right half-plane $\{w: \Re e^{iλ} w>0\}$. Firstly we will characterize $\mathcal{P}_λ$ from different aspects. In section 3, various estimates of functionals over $\mathcal{P}_λ$ are deduced from the k

Timothy E. Goldberg

In this paper, we develop results in the direction of an analogue of Sjamaar and Lerman's singular reduction of Hamiltonian symplectic manifolds in the context of reduction of Hamiltonian generalized complex manifolds (in the sense of Lin and Tolman). Specifically, we prove that if a compact Lie group acts on a generalized complex manifold in a Hamiltoni

Xin-Lin Zhou, Shuang-Nan Zhang

We use publicly available XMM-Newton data to systematically compare the hard X-ray photon indices, $Γ_{\rm 2-10\ keV}$ and the iron K$α$ emission lines of narrow-line (NL) and broad-line Seyfert 1 (BLS1) galaxies. We compile a flux-limited ($f_{\rm 2-10\ keV} \geq 1 \times 10^{-12}$ erg s$^{-1}$ cm$^{-2}$) sample including 114 radio-quiet objects, with the 2

Hirofumi Sakakibara, Hidetomo Usui, Kazuhiko Kuroki, Ryotaro Arita

In order to explore the reason why the single-layered cuprates, La$_{2-x}$(Sr/Ba)$_x$CuO$_4$ ($T_c\simeq$ 40K) and HgBa$_2$CuO$_{4+δ}$ ($T_c\simeq$ 90K), have such a significant difference in $T_c$, we study a two-orbital model that incorporates the $d_{z^2}$ orbital on top of the $d_{x^2-y^2}$ orbital. It is found, with the fluctuation exchange approximatio

Yasufumi Araki, Tetsuo Hatsuda

Using the strong coupling expansion of the compact and non-compact U(1) lattice gauge theory for monolayer graphene, we show analytically that fermion bandgap and pseudo Nambu--Goldstone exciton (pi-exciton) are dynamically generated due to chiral symmetry breaking. The mechanism is similar to the generation of quark mass and pion excitation in quantum chrom

Lorenz Schabrun

We show that for manifolds of dimension $m\geq5$, the flow of a Seiberg-Witten-type functional admits a global smooth solution on $M \times [0,\infty)$.

Huaxin Lin, Zhuang Niu

Let $A$ and $B$ be unital separable simple amenable \CA s which satisfy the Universal Coefficient Theorem. Suppose {that} $A$ and $B$ are $\mathcal Z$-stable and are of rationally tracial rank no more than one. We prove the following: Suppose that $ϕ, ψ: A\to B$ are unital {monomorphisms}. There exists a sequence of unitaries $\{u_n\}\subset B$ such that $$

N. Zacharias, C. Finch, T. Girard, N. Hambly

The third US Naval Observatory (USNO) CCD Astrograph Catalog, UCAC3 was released at the IAU General Assembly on 2009 August 10. It is the first all-sky release in this series and contains just over 100 million objects, about 95 million of them with proper motions, covering about R = 8 to 16 magnitudes. Current epoch positions are obtained from the observatio

J. P. Bergfield, M. Solis, C. A. Stafford

We predict an enormous order-dependent quantum enhancement of thermoelectric effects in the vicinity of a higher-order `supernode' in the transmission spectrum of a nanoscale junction. Single-molecule junctions based on 3,3'-biphenyl and polyphenyl ether (PPE) are investigated in detail. The nonequilibrium thermodynamic efficiency and power output of

S. Ole Warnaar, Wadim Zudilin

The $q$-binomial coefficients $\qbinom{n}{m}=\prod_{i=1}^m(1-q^{n-m+i})/(1-q^i)$, for integers $0\le m\le n$, are known to be polynomials with non-negative integer coefficients. This readily follows from the $q$-binomial theorem, or the many combinatorial interpretations of $\qbinom{n}{m}$. In this note we conjecture an arithmetically motivated generalisatio

Leonardo Modesto, Andrew Randono

It has been known for some time that there is a deep connection between thermodynamics and gravity, with perhaps the most dramatic implication that the Einstein equations can be viewed as a thermodynamic equation of state. Recently Verlinde has proposed a model for gravity with a simple statistical mechanical interpretation that is applicable in the non-rela

Antal Balog, Kevin A. Broughan, Igor E. Shparlinski

For a prime $p$ and an integer $a \in \Z$ we obtain nontrivial upper bounds on the number of solutions to the congruence $x^x \equiv a \pmod p$, $1 \le x \le p-1$. We use these estimates to estimate the number of solutions to the congruence $x^x \equiv y^y \pmod p$, $1 \le x,y \le p-1$, which is of cryptographic relevance.

G. Hagen, T. Papenbrock, M. Hjorth-Jensen

We perform coupled-cluster calculations of the energies and lifetimes of single-particle states around the doubly magic nucleus 16O based on chiral nucleon-nucleon interactions at next-to-next- to-next-to-leading order. To incorporate effects from the scattering continuum, we solve the coupled- cluster equations with a Gamow-Hartree-Fock basis. Our calculati

Jinshan Wu, Mona Berciu

We demonstrate that the proper calculation of the linear response for finite-size systems can only be performed if the coupling to the leads/baths is explicitly taken into consideration. We exemplify this by obtaining a Kubo-type formula for heat transport in a finite-size system coupled to two thermal baths, kept at different temperatures. We show that the

Martin C. Weisskopf

We review the history of the development of the Chandra X-ray Observatory from our personal perspective. This review is necessarily biased and limited by space since it attempts to cover a time span approaching 5 decades.

Weiwei Zhu, Victoria M. Kaspi

Anomalous X-ray Pulsars (AXPs) are now established to exhibit significant X-ray variability and be prolific glitchers, with some glitches being accompanied by large radiative changes. An open issue is whether AXP glitches are generically accompanied by radiative changes, relevant for understanding magnetar physical properties. Here we report on an analysis o

Elena Mason, G. L. Israel, S. Dall'Osso, L. Stella

A 321.5 s modulation was discovered in 1999 in the X-ray light curve of HM Cnc. In 2001 and 2002, optical photometric and spectroscopic observations revealed that HM Cnc is a very blue object with no intrinsic absorptions but broad (FWHM 1500 km s^-1) low equivalent width emission lines (EW 1-6A), which were first identified with the HeII Pickering series. T

Gregor Dolinar, Alexander E. Guterman, Bojan Kuzma, Marko Orel

Let $\FF$ be a finite field of characteristics different from two. We show that no bijective map transforms permanent into determinant when the cardinality of $\FF$ is sufficiently large. We also give an example of non-bijective map when $\FF$ is arbitrary and an example of a bijective map when $\FF$ is infinite which do transform permanent into determinant.

Xin-She Yang, Y. Young

State-of-the-art review of cellular automata, cellular automata for partial differential equations, differential equations for cellular automata and pattern formation in biology and engineering.

Konstantin Bobkov, Volker Braun, Piyush Kumar, Stuart Raby

We describe a simple and robust mechanism that stabilizes all Kahler moduli in Type IIB orientifold compactifications. This is shown to be possible with just one non-perturbative contribution to the superpotential coming from either a D3-instanton or D7-branes wrapped on an ample divisor. This moduli-stabilization mechanism is similar to and motivated by the

Aaron Robotham, Steve Phillipps, Roberto de Propris

We explore the shape of the galaxy luminosity function (LF) in groups of different mass by creating composite LFs over large numbers of groups. Following previous work using total group luminosity as the mass indicator, here we split our groups by multiplicity and by estimated virial (group halo) mass, and consider red (passive) and blue (star forming) galax

Rongxin Huang, Branimir Lukic, Sylvia Jeney, Ernst-Ludwig Florin

At fast timescales, the self-similarity of random Brownian motion is expected to break down and be replaced by ballistic motion. So far, an experimental verification of this prediction has been out of reach due to a lack of instrumentation fast and precise enough to capture this motion. With a newly developed detector, we have been able to observe the Browni

D. A. Abanin, S. A. Parameswaran, S. A. Kivelson, S. L. Sondhi

The interplay between quantum Hall ordering and spontaneously broken "internal" symmetries in two-dimensional electron systems with spin or pseudospin degrees of freedom gives rise to a variety of interesting phenomena, including novel phases, phase transitions, and topological excitations. Here we develop a theory of broken-symmetry quantum Hall sta

A. A. Kordyuk, D. V. Evtushinsky, V. B. Zabolotnyy, T. Haenke

Powered by effective parquet nesting a commensurate chiral honeycomb superstructure in a trigonally packed transition metal dichalcogenide TaSe$_2$ results in a Dirac cone anomaly in one-particle excitation spectrum. However, the formation of the well defined Dirac point seems to be hindered by effective scattering on 2D plasmons.

Hao Guo, Chih-Chun Chien, K. Levin

We show how the difference between the finite temperature T structure factors, called S_-, associated with spin and density, can be used as a indication of superfluidity in ultracold Fermi gases. This observation can be exploited in two photon Bragg scattering experiments on gases which undergo BCS- Bose Einstein condensation crossover. Essential to our calc

Brian A. Ruzicka, Hui Zhao

We investigate the power dependence of pure spin current injection in GaAs bulk and quantum-well samples by a quantum interference and control technique. Spin separation is measured as a function of the relative strength of the two transition pathways driven by two laser pulses. By keeping the relaxation time of the current unchanged, we are able to relate t

Sean B. Gryb

We propose a definition for background (in)/dependence in dynamical theories of the evolution of configurations that have a continuous symmetry and test this definition on particle models and on gravity. Our definition draws from Barbour's best-matching framework developed for the purpose of implementing spatial and temporal relationalism. Among other in

Joost Melai, Alexey Lyashenko, Amos Breskin, Harry van der Graaf

Preliminary results of a photon detector combining a Micromegas like multiplier coated with a UV-sensitive CsI photocathode are described. The multiplier is made in a CMOS compatible InGrid technology, which allows to post-process it directly on the surface of an imaging IC. This method is aimed at building light-sensitive imaging detectors where all element

Hector Pasten

We prove a result on the representation of squares by second degree polynomials in the field of $p$-adic meromorphic functions in order to solve positively Büchi's $n$ squares problem in this field (that is, the problem of the existence of a constant $M$ such that any sequence $(x_n^2)$ of $M$ - not all constant - squares whose second difference is the c

Yann-Aël Le Borgne, Sylvain Raybaud, Gianluca Bontempi

The Principal Component Analysis (PCA) is a data dimensionality reduction technique well-suited for processing data from sensor networks. It can be applied to tasks like compression, event detection, and event recognition. This technique is based on a linear transform where the sensor measurements are projected on a set of principal components. When sensor m

D. Mendoza, J. L. Benitez, F. Morales, R. Escudero

Synthesis, electrical and magnetic characterization of superconducting FeSe0.85 compound is reported. An anomaly in the magnetization against temperature around 90K is observed. Magnetic characterization of a commercial compound with nominal FeSe stoichiometry is also presented. The overall magnetic behaviors as well as the magnetic anomaly in both compounds

Mikhail Yu. Kalmykov, Bernd A. Kniehl

We briefly sketch a proof concerning the structure of the all-order epsilon-expansions of generalized hypergeometric functions with special sets of parameters.

Maria Santos-Lleo, Norbert Schartel, Harvey Tananbaum, Wallace Tucker

NASA's Chandra X-ray Observatory and ESA's XMM-Newton made their first observations one decade ago. The unprecedented and complementary capabilities of these observatories to detect, image, and measure the energy of cosmic X-rays, achieved less than 50 years after the first detection of an extra-solar X-ray source, represent an increase in sensitivit

Joshua D. Bodyfelt, Tsampikos Kottos, Boris Shapiro

We show, using detailed numerical analysis and theoretical arguments, that the normalized participation number of the stationary solutions of disordered nonlinear lattices obeys a one-parameter scaling law. Our approach opens a new way to investigate the interplay of Anderson localization and nonlinearity based on the powerful ideas of scaling theory.

Alan Frieze, Michael Krivelevich

We say that a $k$-uniform hypergraph $C$ is a Hamilton cycle of type $\ell$, for some $1\le \ell \le k$, if there exists a cyclic ordering of the vertices of $C$ such that every edge consists of $k$ consecutive vertices and for every pair of consecutive edges $E_{i-1},E_i$ in $C$ (in the natural ordering of the edges) we have $|E_{i-1}-E_i|=\ell$. We prove t

Robert Yuncken

Let $σ$ be the involution of the Roe algebra $\Roe{\RR}$ which is induced from the reflection $\RR\to\RR; x\mapsto -x$. A graded Fredholm module over a separable $C^*$-algebra $A$ gives rise to a homomorphism $\tildeρ:A\to\Roe{\RR}^σ$ to the fixed-point subalgebra. We use this observation to give an even-dimensional analogue of a result of Roe. Namely, we sh

Eleazar R. Carrasco, Christopher J. Conselice, I. Trujillo

We present deep K-band adaptive-optics observations of eight very massive (M* ~ 4 x 10^11 Msun) galaxies at 1 < z < 2 utilizing the Gemini NIRI/Altair Laser Guide System. These systems are selected from the Palomar Observatory Wide-Field Infrared (POWIR) survey, and are amongst the most massive field galaxies at these epochs. The depth and high spatial resol

L. B. Castro, A. S. de Castro

It is shown that the paper &#34;Wave functions for a Duffin-Kemmer-Petiau particle in a time-dependent potential&#34;, by Merad and Bensaid [J. Math. Phys. 48, 073515 (2007)] is not correct in using inadvertently a non-Hermitian Hamiltonian in a formalism that does require Hermitian Hamiltonians.

Zhou Li, D. Baillie, C. Blois, F. Marsiglio

We adapt a variational procedure to calculate ground state properties of the Holstein model in the adiabatic limit. At strong coupling, this adaption leads to rapid convergence of results. The intermediate coupling regime is further handled with an adaptive algorithm. We also use semi-classically derived results for the adiabatic end-point, along with weak c

Ad Ridder

The correspondence between the cross-entropy method and the zero-variance approximation to simulate a rare event problem in Markov chains is shown. This leads to a sufficient condition that the cross-entropy estimator is asymptotically optimal.

Agnieszka Pollo, Piotr Rybka, Tsutomu T. Takeuchi

To separate stars and galaxies in the far infrared AKARI All-Sky Survey data, we have selected a sample with the complete color information available in the low extinction regions of the sky and constructed color-color plots for these data. We looked for the method to separate stars and galaxies using the color information. We performed an extensive search f

Mihai Anastasiei

A linear connection $D$ in a Lie algebroid is said to be metrizable if there exists a Riemannian metric $h$ in the Lie algebroid such that $Dh=0$. Conditions for the linear connection $D$ to be metrizable are investigated.

Nicolás González-Jiménez, Cristóbal Petrovich, Andreas Reisenegger

When a rotating neutron star loses angular momentum, the reduction of the centrifugal force makes it contract. This perturbs each fluid element, raising the local pressure and originating deviations from beta equilibrium, inducing reactions that release heat (rotochemical heating). This effect has previously been studied by Fernández and Reisenegger for neut

F. P. Mancini

We study the influence of an external magnetic field h on the phase diagram of a system of Fermi particles living on the sites of a Bethe lattice with coordination number z and interacting through on-site U and nearest-neighbor V interactions. This is a physical realization of the extended Hubbard model in the narrow-band limit. Our results establish that th

Danhong Huang, Godfrey Gumbs

When impurity and phonon scattering coexist, the Boltzmann equation has been solved accurately for nonlinear electron transport in a quantum wire. Based on the calculated non-equilibrium distribution of electrons in momentum space, the scattering effects on both the non-differential (for a fixed dc field) and differential (for a fixed temperature) mobilities

J. Glister, G. Ron, B. W. Lee, R. Gilman

High precision measurements of induced and transferred recoil proton polarization in d(polarized gamma, polarized p})n have been performed for photon energies of 277--357 MeV and theta_cm = 20 degrees -- 120 degrees. The measurements were motivated by a longstanding discrepancy between meson-baryon model calculations and data at higher energies. At the low e

Matthias C. Hoffmann, Dmitry Turchinovich

We demonstrate saturable absorber behavior of n-type semiconductors GaAs, GaP and Ge in THz frequency range at room temperature using nonlinear THz spectroscopy. The saturation mechanism is based on a decrease in electron conductivity of semiconductors at high electron momentum states, due to conduction band nonparabolicity and scattering into satellite vall

Hernan L. Calvo, Horacio M. Pastawski

The time-reversal mirror (TRM) prescribes the reverse playback of a signal to focalize an acoustic excitation as a Loschmidt echo. In the quantum domain, the perfect inverse filter (PIF) processes this signal to ensure an exact reversion provided that the excitation originated outside the cavity delimited by the transducers. We show that PIF takes a simple f