April 2010 arXiv papers — page 15

David Conlon, Jacob Fox, Benny Sudakov

A beautiful conjecture of Erdős-Simonovits and Sidorenko states that if H is a bipartite graph, then the random graph with edge density p has in expectation asymptotically the minimum number of copies of H over all graphs of the same order and edge density. This conjecture also has an equivalent analytic form and has connections to a broad range of topics, s

Zhi-zhong Xing, Deshan Yang, Shun Zhou

We apply the discrete S_3 flavor symmetry to both lepton and quark sectors of the standard model extended by introducing one Higgs triplet and realizing the type-II seesaw mechanism for finite neutrino masses. The resultant mass matrices of charged leptons (M_l), neutrinos (M_nu), up-type quarks (M_u) and down-type quarks (M_d) have a universal form consisti

Chuanwei Zhang

We propose a scheme for generating Rashba spin-orbit coupling and perpendicular Zeeman field simultaneously for cold fermionic atoms in a harmonic trap through the coupling between atoms and laser fields. The realization of Rashba spin-orbit coupling and perpendicular Zeeman field provides opportunities for exploring many topological phenomena using cold fer

Zhong Wang, Xiao-Liang Qi, Shou-Cheng Zhang

We propose a topological order parameter for interacting topological insulators, expressed in terms of the full Green's functions of the interacting system. We show that it is exactly quantized for a time reversal invariant topological insulator, and it can be experimentally measured through the topological magneto-electric effect. This topological order par

Sergio Giardino, Hector L. Carrion

The purpose of this study is to extend the concept of a generalized Lie $3-$ algebra, known to the divisional algebra of the octonions $\mathbb{O}$, to split-octonions $\mathbb{SO}$, which is non-divisional. This is achieved through the unification of the product of both of the algebras in a single operation. Accordingly, a notational device is introduced to

Lori McDonnell

We consider a conjecture of Watanabe and Yoshida concerning the Hilbert - Kunz multiplicity of an ideal in a Cohen-Macaulay ring and provide a proof of the conjecture in the case the ring is graded.

Gongguo Tang, Arye Nehorai

The stability of sparse signal reconstruction is investigated in this paper. We design efficient algorithms to verify the sufficient condition for unique $\ell_1$ sparse recovery. One of our algorithm produces comparable results with the state-of-the-art technique and performs orders of magnitude faster. We show that the $\ell_1$-constrained minimal singular

Nathaniel Craig

The observed hierarchy of fermion masses and mixings may be generated by renormalization group flow if the Standard Model is coupled to a near-conformal sector at high energies. If the conformal sector is supersymmetric, these effects are rendered calculable by a combination of superconformal symmetry and a-maximization. The viability of such models depends

Brian D. Metzger

A small fraction of core collapse supernovae (SNe) show evidence that the outgoing blast wave has encountered a substantial mass ~ 1-10 M_sun of circumstellar matter (CSM) at radii ~100-1000 AU, much more than can nominally be explained by pre-explosion stellar winds. In extreme cases this interaction may power the most luminous, optically-energetic SNe yet

Daniel Arean, Eduardo Conde, Alfonso V. Ramallo, Dimitrios Zoakos

We obtain gravity duals to supersymmetric gauge theories in two and three spacetime dimensions with unquenched flavor. The supergravity solutions are generated by a set of color branes wrapping a compact cycle in a Calabi-Yau threefold, together with another set of flavor branes extended along the directions orthogonal to the cycle wrapped by the color brane

Denis Pollney, Christian Reisswig

In addition to the dominant oscillatory gravitational wave signals produced during binary inspirals, a non-oscillatory component arises from the nonlinear "memory" effect, sourced by the emitted gravitational radiation. The memory grows significantly during the late inspiral and merger, modifying the signal by an almost step-function profile, and mak

Florent Jouve, Fernando Rodriguez-Villegas

This paper is partly a survey of known results on quadratic forms that are hard to find in the literature. Our main focus is a twisted form of a construction due to Bezout. This skew Bezoutian is a symplectic (resp. quadratic) space associated to a pair of reciprocal (or skew reciprocal) coprime polynomials of same degree. The isometry group of this space tu

D. Yu. Akimov, H. M. Araujo, E. J. Barnes, V. A. Belov

The design, optimisation and construction of an anti-coincidence veto detector to complement the ZEPLIN-III direct dark matter search instrument is described. One tonne of plastic scintillator is arranged into 52 bars individually read out by photomultipliers and coupled to a gadolinium-loaded passive polypropylene shield. Particular attention has been paid

Beatriz Gato, Beatriz Gato-Rivera

We introduce the `Complete Wave Function' and deduce that all living beings, not just Schroedinger's cat, are actually described by a superposition of `alive' and `dead' quantum states; otherwise they would never die. Therefore this proposal provides a quantum mechanical explanation to the world-wide observation that we all pass away. Next we

Yichao Tian

Let $\cO_K$ be a complete discrete valuation ring of residue characteristic $p>0$, and $G$ be a finite flat group scheme over $\cO_K$ of order a power of $p$. We prove in this paper that the Abbes-Saito filtration of $G$ is bounded by a simple linear function of the degree of $G$. Assume $\cO_K$ has generic characteristic 0 and the residue field of $\cO_K$ i

Laura Schaefer, Bruce Fegley

We use thermodynamic calculations to model atmospheric chemistry on terrestrial exoplanets that are hot enough for chemical equilibira between the atmosphere and lithosphere, as on Venus. The results of our calculations place constraints on abundances of spectroscopically observable gases, the surface temperature and pressure, and the mineralogy of the surfa

A. V. Smirnov, A. V. Petukhov

For a fixed Feynman graph one can consider Feynman integrals with all possible powers of propagators and try to reduce them, by linear relations, to a finite subset of integrals, the so-called master integrals. Up to now, there are numerous examples of reduction procedures resulting in a finite number of master integrals for various families of Feynman integ

Wu-yen Chuang, Duiliu-Emanuel Diaconescu, Guang Pan

A conjectural recursive relation for the Poincaré polynomial of the Hitchin moduli space is derived from wallcrossing in the refined local Donaldson-Thomas theory of a curve. A doubly refined generalization of this theory is also conjectured and shown to similarly determine the Hodge polynomial of the same moduli space.

Bruno Iochum, Thierry Masson, Thomas Schücker, Andrzej Sitarz

We construct discrete versions of $κ$-Minkowski space related to a certain compactness of the time coordinate. We show that these models fit into the framework of noncommutative geometry in the sense of spectral triples. The dynamical system of the underlying discrete groups (which include some Baumslag--Solitar groups) is heavily used in order to construct

Cristóbal Rivas

We study the space of left-orderings on groups with finitely many Conradian orderings. We show that, within this class of groups, having an isolated left-ordering is equivalent to having finitely many left-orderings.

Francis Bailly, Giuseppe Longo, Maël Montévil

This paper proposes an abstract mathematical frame for describing some features of biological time. The key point is that usual physical (linear) representation of time is insufficient, in our view, for the understanding key phenomena of life, such as rhythms, both physical (circadian, seasonal ...) and properly biological (heart beating, respiration, metabo

Piero Olla

The optimal strategy for a microscopic swimmer to migrate across a linear shear flow is discussed. The two cases, in which the swimmer is located at large distance, and in the proximity of a solid wall, are taken into account. It is shown that migration can be achieved by means of a combination of sailing through the flow and swimming, where the swimming str

O. Lübben, L. Dudy, A. Krapf, C. Janowitz

In the Bi cuprates, the presence of a near 1$\times$5 superstructure is well known. Usually, this superstructure is suppressed by the substitution of lead, but there have been reports of a phase separation in so called α and β phases. This paper shows in high detail time how and why the phase separation develops and what happens to the quasi-1$\times$5 super

Aleksey Kostenko, Alexander Sakhnovich, Gerald Teschl

We investigate the eigenvalues of perturbed spherical Schrödinger operators under the assumption that the perturbation $q(x)$ satisfies $x q(x) \in L^1(0,1)$. We show that the square roots of eigenvalues are given by the square roots of the unperturbed eigenvalues up to an decaying error depending on the behavior of $q(x)$ near $x=0$. Furthermore, we provide

Jiro Akahori, Takafumi Amaba, Sachiyo Uraguchi

In this paper, we will give a new perspective to the Cameron-Martin-Maruyama-Girsanov formula by giving a totally algebraic proof to it. It is based on the exponentiation of the Malliavin-type differentiation and its adjointness.

Nick Wright

In this paper we prove that the asymptotic dimension of a finite-dimensional CAT(0) cube complex is bounded above by the dimension. To achieve this we prove a controlled colouring theorem for the complex. We also show that every CAT(0) cube complex is a contractive retraction of an infinite dimensional cube. As an example of the dimension theorem we obtain b

Fan Qin

For skew-symmetric acyclic quantum cluster algebras, we express the quantum $F$-polynomials and the quantum cluster monomials in terms of Serre polynomials of quiver Grassmannians of rigid modules. As byproducts, we obtain the existence of counting polynomials for these varieties and the positivity conjecture with respect to acyclic seeds. These results comp

Fabio Caccioli, Susanne Still, Matteo Marsili, Imre Kondor

We consider the problem of portfolio optimization in the presence of market impact, and derive optimal liquidation strategies. We discuss in detail the problem of finding the optimal portfolio under Expected Shortfall (ES) in the case of linear market impact. We show that, once market impact is taken into account, a regularized version of the usual optimizat

Piotr Przytycki, Jennifer Schultens

Kakimizu complex of a knot is a flag simplicial complex whose vertices correspond to minimal genus Seifert surfaces and edges to disjoint pairs of such surfaces. We discuss a general setting in which one can define a similar complex. We prove that this complex is contractible, which was conjectured by Kakimizu. More generally, the fixed-point set (in the Kak

Sourav K. Mandal, Mihoko Nojiri, Matthew Sudano, Tsutomu T. Yanagida

The hierarchy of the Yukawa couplings is an outstanding problem of the standard model. We present a class of models in which the first and second generation fermions are SUSY partners of pseudo-Nambu-Goldstone bosons that parameterize a non-compact Kahler manifold, explaining the small values of these fermion masses relative to those of the third generation.

Wei-Bo Gao, Xing-Can Yao, Jian-Ming Cai, He Lu

The paradigm of measurement-based quantum computation opens new experimental avenues to realize a quantum computer and deepens our understanding of quantum physics. Measurement-based quantum computation starts from a highly entangled universal resource state. For years, clusters states have been the only known universal resources. Surprisingly, a novel frame

Pekka Salmi

We show that there is a one-to-one correspondence between compact quantum subgroups of a co-amenable locally compact quantum group $\mathbb{G}$ and certain left invariant C*-subalgebras of $C_0(\mathbb{G})$. We also prove that every compact quantum subgroup of a co-amenable quantum group is co-amenable. Moreover, there is a one-to-one correspondence between

J. F. DiTusa, R. G. Goodrich, N. Harrison, E. S. Choi

We have measured de Haas-van Alphen oscillations of Cr$_{1-x}$V$_x$, $0 \le x \le 0.05$, at high fields for samples on both sides of the quantum critical point at $x_c=0.035$. For all samples we observe only those oscillations associated with a single small hole band with magnetic breakdown orbits of the reconstructed Fermi surface evident for $x<x_c$. The a

C. Male

Let X_N= (X_1^(N), ..., X_p^(N)) be a family of N-by-N independent, normalized random matrices from the Gaussian Unitary Ensemble. We state sufficient conditions on matrices Y_N =(Y_1^(N), ..., Y_q^(N)), possibly random but independent of X_N, for which the operator norm of P(X_N, Y_N, Y_N^*) converges almost surely for all polynomials P. Limits are describe

Swarup kumar Mitra, Ayon Chakraborty, Subhajit Mandal, M. K. Naskar

This paper has been withdrawn by the author due to a crucial sign error in equation 1

Peter Tankov

Improved bounds on the copula of a bivariate random vector are computed when partial information is available, such as the values of the copula on a given subset of $[0,1]^2$, or the value of a functional of the copula, monotone with respect to the concordance order. These results are then used to compute model-free bounds on the prices of two-asset options

Jean-Daniel Bancal, Nicolas Gisin, Stefano Pironio

Finding all Bell inequalities for a given number of parties, measurement settings, and measurement outcomes is in general a computationally hard task. We show that all Bell inequalities which are symmetric under the exchange of parties can be found by examining a symmetrized polytope which is simpler than the full Bell polytope. As an illustration of our met

A. Cano, M. Civelli, I. Eremin, I. Paul

The interplay between the structural and magnetic phase transitions occurring in the Fe-based pnictide superconductors is studied within a Ginzburg-Landau approach. We show that the magnetoelastic coupling between the corresponding order parameters is behind the salient features observed in the phase diagram of these systems. This naturally explains the coin

Stefano Giusto, Samir D. Mathur

The traditional black hole has a horizon, with a singularity inside the horizon. But actual microstates of black holes are `fuzzballs&#39;, with no horizon and a complex internal structure. We take the simplest hole in string theory -- the extremal 2-charge D1D5 hole -- and study a simple effect that is a consequence of this internal structure of the fuzzbal

J. Z. Farkas, P. Hinow

We consider a linear size-structured population model with diffusion in the size-space. Individuals are recruited into the population at arbitrary sizes. The model is equipped with generalized Wentzell-Robin (or dynamic) boundary conditions. This allows modelling of "adhesion" at extremely small or large sizes. We establish existence and positivity of soluti

Martin Hartvig, Ken H. Andersen, Jan E. Beyer

We synthesise traditional unstructured food webs, allometric body size scaling, trait-based modelling, and physiologically structured modelling to provide a novel and ecologically relevant tool for size-structured food webs. The framework allows food web models to include ontogenetic growth and life-history omnivory at the individual level by resolving the p

Piotr Szankowski, Eryk Infeld, Marek Trippenbach, George Rowlands

We investigate the properties of three component BEC systems with spin exchange interactions. We consider different coupling constants from those leading to exact solutions known in the literature. When two solitons collide, an oscillation of the emerging entities is observed. This behavior seems to be generic. A mathematical model is derived for the emergin

R. Dvorak, J. Schneider, V. Eybl

We propose a method to be able to decide whether the planets of CoRoT-7 are moving on mutually inclined orbits in the order of i > 10 degrees. The extrasolar system CoRoT-7 is very special with respect to the closeness of the planets to the host star, which results in a fast dynamical development. It would therefore be possible to determine the inclination o

Emanuel Gluskin

One-ports named &#34;f-circuits&#34;, composed of similar conductors described by a monotonic polynomial, or quasi-polynomial (i.e. with positive but not necessarily integer, powers) characteristic i = f(v) are studied, focusing on the algebraic map f --> F. Here F(.) is the input conductivity characteristic; i.e., iin = F(vin) is the input current. The &#34

Anna Benini, Luca Giuzzi, Anita Pasotti

Let G&#39; be a subgraph of a graph G. We define a down-link from a (K_v,G)-design B to a (K_n,G&#39;)-design B&#39; as a map f:B->B&#39; mapping any block of B into one of its subgraphs. This is a new concept, closely related with both the notion of metamorphosis and that of embedding. In the present paper we study down-links in general and prove that any (

Lene Sælen, Erik Waltersson, J. P. Hansen, Eva Lindroth

We demonstrate that conditional as well as unconditional basic operations which are prerequisite for universal quantum gates can be performed with almost 100% fidelity within a strongly interacting two-electron quantum ring. Both sets of operations are based on a quantum control algorithm that optimizes a driving electromagnetic pulse for a given quantum gat

A. P. Bakulev, S. V. Mikhailov, N. G. Stefanis

Results on the resummation of non-power-series expansions of the Adler function of a scalar, $D_S$, and a vector, $D_V$, correlator are presented within fractional analytic perturbation theory (FAPT). The first observable can be used to determine the decay width $Γ_{H\to b\bar{b}}$ of a scalar Higgs boson to a bottom-antibottom pair, while the second one is

Jeongho Bang, Seokwon Yoo, James Lim, Junghee Ryu

We propose a quantum heuristic algorithm to solve a traveling salesman problem by generalizing Grover search. Sufficient conditions are derived to greatly enhance the probability of finding the tours with extremal costs, reaching almost to unity and they are shown characterized by statistical properties of tour costs. In particular for a Gaussian distributio

Mark Oxborrow, Pierre-Yves Bourgeois, Yann Kersalé, Vincent Giordano

The zero-field Fe3+:sapphire whispering-gallery-mode maser oscillator exhibits several alluring features: Its output is many orders of magnitude brighter than that of an active hydrogen maser and thus far less degraded by spontaneous-emission (Schawlow-Townes) and/or receiving-amplifier noise. Its oscillator loop is confined to a piece of mono-crystalline ro

David Barnes, Constanze Roitzheim

We discuss the monoidal structure on Franke&#39;s algebraic model for the $K_{(p)}$-local stable homotopy category at odd primes and show that its Picard group is isomorphic to the integers.

V. V. Kiselev, S. A. Timofeev

We argue for a model of low-energy correction to the inflationary potential as caused by the gauge-mediated breaking down the supersymmetry at the scale of $μ_\textsc{x}\sim 10^4$ GeV, that provides us with the seesaw mechanism of thin domain wall fluctuations in the flat vacuum. The fluctuations are responsible for the vacuum with the cosmological constant

Zuzana Carikova, Augustin Skopal

In the optical, the spectrum of symbiotic binaries consists of contributions from the cool giant, symbiotic nebula and the hot star. Strong emission lines are superposed on the continuum. In this paper we introduce a simple method to extract individual components of radiation from photometric UBV magnitudes. We applied the method to classical symbiotic stars

Arpita Ghosh, Somenath Chakrabarty

Following an extremely interesting idea \cite{R1}, published long ago, the work function associated with the emission of ultra-relativistic electrons from magnetically deformed metallic crystal of astrophysical relevance is obtained using relativistic version of Thomas-Fermi type model. In the present scenario, surprisingly, the work function becomes anisotr

J. Hejtmánek, E. Šantavá, K. Knížek, M. Maryško

The magnetic, electric and thermal properties of the ($Ln_{1-y}$Y$_{y}$)$_{0.7}$Ca$_{0.3}$CoO$_3$ perovskites ($Ln$~=~Pr, Nd) were investigated down to very low temperatures. The main attention was given to a peculiar metal-insulator transition, which is observed in the praseodymium based samples with $y=0.075$ and 0.15 at $T_{M-I}=64$ and 132~K, respectivel

Avraham Gal

I conjecture that the time modulated decay rates reported in single ion measurements of two body electron capture decay of hydrogen like heavy ions at GSI may be related to neutrino spin precession in the static magnetic field of the storage ring. These `GSI Oscillations&#39; arise from interference between amplitudes of decay within and without the magnetic

L. Fabbietti, H. Angerer, R. Beck, M. Berger

We report on the development of a GEM-based TPC prototype for the PANDA experiment. The design and requirements of this device will be illustrated, with particular emphasis on the properties of the recently tested GEM-detector, the characterization of the read-out electronics and the development of the tracking software that allows to evaluate the GEM-TPC da

Kazutoshi Ohta, Norisuke Sakai

A mechanism using the position-dependent gauge coupling is proposed to localize non-Abelian gauge fields on domain walls in five-dimensional space-time. Low-energy effective theory posseses a massless vector field, and a mass gap. The four-dimensional gauge invariance is maintained intact. We obtain perturbatively the four-dimensional Coulomb law for static

Jean-Claude Belfiore, Frédérique Oggier

We propose the notion of secrecy gain as a code design criterion for wiretap lattice codes to be used over an additive white Gaussian noise channel. Our analysis relies on the error probabilites of both the legitimate user and the eavesdropper. We focus on geometrical properties of lattices, described by their theta series, to characterize good wiretap codes

Olivier Delmas, Sylvain Gravier, Mickael Montassier, Aline Parreau

Identifying codes have been introduced in 1998 to model fault-detection in multiprocessor systems. In this paper, we introduce two variations of identifying codes: weak codes and light codes. They correspond to fault-detection by successive rounds. We give exact bounds for those two definitions for the family of cycles.

Elahe Zohoorian Azad, Philippe Chassaing

In this paper we consider the normalized lengths of the factors of some factorizations of random words. First, for the \emph{Lyndon factorization} of finite random words with $n$ independent letters drawn from a finite or infinite totally ordered alphabet according to a general probability distribution, we prove that the limit law of the normalized lengths o

Mubasher Jamil, M. Akbar, M. R. Setare

It is shown that the Bekenstein-Hawking entropy of an axially symmetric dilaton-axion black hole can be expressed as a Cardy-Verlinde formula. By utilizing the first order quantum correction in the Bekenstein-Hawking entropy we find the modified expressions for the Casimir energy and pure extensive energy. The first order correction to the Cardy-Verlinde for

Benjamin J. Galow, Zoltán Harman, Christoph H. Keitel

During the past decade, the interaction of high-intensity lasers with solid targets has attracted much interest, regarding its potential in accelerating charged particles. In spite of tremendous progress in laser-plasma based acceleration, it is still not clear which particle beam quality will be accessible within the upcoming multi petawatt (1 PW = 10$^{15}

Ansis Rosmanis

I introduce a new type of continuous-time quantum walk on graphs called the quantum snake walk, the basis states of which are fixed-length paths (snakes) in the underlying graph. First I analyze the quantum snake walk on the line, and I show that, even though most states stay localized throughout the evolution, there are specific states which most likely mov

Haidong Yuan, Christiane Koch, Peter Salamon, David Tannor

We consider the optimal control problem of transferring population between states of a quantum system where the coupling proceeds only via intermediate states that are subject to decay. We pose the question whether it is generally possible to carry out this transfer. For a single intermediate decaying state, we recover the Stimulated Raman Adiabatic Passage

Chi Li

In this note, using Calabi&#39;s method, we construct rotationally symmetric Kahler-Ricci solitons on the total space of direct sum of fixed hermitian line bundle and its projective compactification, where the curvature of hermitian line bundle is Kahler-Einstein. These examples generalize the construction of Koiso, Cao and Feldman-Ilmanen-Knopf.

Hong Ma, Zuanming Jin, Lihua Wang, Guohong Ma

Electron spin dynamics in intrinsic bulk Indium Phosphide (InP) semiconductor is studied by time resolved pump probe reflectivity (TRPPR) technique using the co- and counter-circularly polarized femtosecond pulses at room temperature and 70 K. The reflectivity change from bleaching into absorption is observed with increasing pump photon energy, which can be

Sujit K. Mondal

One pot synthetic technique was used to synthesize mesoporous fullerene using highly ordered mesoporous template such as KIT6-150 and SBA-15-150. Highly ordered porous fullerene with cross linkage between the fullerene molecules was obtained at high temperature 900 0C. This type of highly ordered and high surface area mesoporous fullerence was used as cataly

Yukimichi Tamaki, Yu Kataoka, Takashi Miyazaki

A new strategy with bone tissue engineering by mesenchymal stem cell transplantation on titanium implant has been dawn attention. The surface scaffold properties of titanium surface play an important role in bone regenerative potential of cells. The surface topography and chemistry are postulated to be two major factors increasing the scaffold properties of

Takafumi Kanamori, Hiroaki Uehara, Masakazu Jimbo

We study the group test for DNA library screening based on probabilistic approach. Group test is a method of detecting a few positive items from among a large number of items, and has wide range of applications. In DNA library screening, positive item corresponds to the clone having a specified DNA segment, and it is necessary to identify and isolate the pos

Jongjeong Kim, Weonjong Lee, Stephen R. Sharpe

We present results for one-loop perturbative matching factors using bilinear operators composed of improved staggered fermions, using unimproved (Wilson) and improved (Symanzik, Iwasaki, and DBW2) gluon actions. We consider two fermions actions---HYP/$\bar{\text{Fat7}}$-smeared and &#34;asqtad&#34;. The former is being used in calculations of electroweak mat

Jan de Gier, Bernard Nienhuis, Anita Ponsaing

Employing an inhomogeneous solvable lattice model, we derive an exact expression for a boundary-to-boundary edge current on a lattice of finite width. This current is an example of a class of parafermionic observables recently introduced in an attempt to rigorously prove conformal invariance of the scaling limit of critical two-dimensional lattice models. It

Christopher M. Graney

G. B. Riccioli&#39;s 1651 Almagestum Novum contains a table of diameters of stars measured by Riccioli and his associates with a telescope. These telescopically measured star diameters are spurious, caused by the diffraction of light waves through the circular aperture of the telescope, but astronomers of the time, including Riccioli and Galileo Galilei, wer

Bin Hu, Xiao-Lin Chen, Zhi-Gang Luo, Peng-Zhi Huang

The P-wave charm-strange mesons $D_{s0}(2317)$ and $D_{s1}(2460)$ lie below the $DK$ and $D^\ast K$ threshold respectively. They are extremely narrow because their strong decays violate the isospin symmetry. We study the possible heavy molecular states composed of a pair of excited charm strange mesons. As a byproduct, we also present the numerical results f

Xin Chen, Rhonda Dzakpasu

Complexity in the temporal organization of neural systems may be a reflection of the diversity of its neural constituents. These constituents, excitatory and inhibitory neurons, comprise an invariant ratio in vivo and form the substrate for rhythmic oscillatory activity. To begin to elucidate the dynamical mechanisms that underlie this balance, we construct

Daniel Skodlerack

P. Broussous and S. Stevens studied maps between enlarged Bruhat-Tits buildings to construct types for p-adic unitary groups. They needed maps which respect the Moy-Prasad filtrations. That property is called (CLF), i.e. compatibility with the Lie algebra filtrations. In the first part of this thesis we generalise their results on such maps to the Quaternion

Bacim Alali, Robert Lipton

A methodology is presented for investigating the dynamics of heterogeneous media using the nonlocal continuum model given by the peridynamic formulation. The approach presented here provides the ability to model the macroscopic dynamics while at the same time resolving the dynamics at the length scales of the microstructure. Central to the methodology is a n

Christian Iliadis, Richard Longland, Art Champagne, Alain Coc

Numerical values of charged-particle thermonuclear reaction rates for nuclei in the A=14 to 40 region are tabulated. The results are obtained using a method, based on Monte Carlo techniques, that has been described in the preceding paper of this series (Paper I). We present a low rate, median rate and high rate which correspond to the 0.16, 0.50 and 0.84 qua

Anirban Dasgupta, Ravi Kumar, Tamás Sarlós

Dimension reduction is a key algorithmic tool with many applications including nearest-neighbor search, compressed sensing and linear algebra in the streaming model. In this work we obtain a {\em sparse} version of the fundamental tool in dimension reduction --- the Johnson--Lindenstrauss transform. Using hashing and local densification, we construct a spars

Alan Frieze, Gregory Sorkin

We consider multi-dimensional assignment problems in a probabilistic setting. Our main results are: (i) A new efficient algorithm for the 3-dimensional planar problem, based on enumerating and selecting from a set of &#34;alternating-path trees&#34;; (ii) A new efficient matching-based algorithm for the 3-dimensional axial problem.

David Broadhurst

This is an expansion of a talk for mathematics and physics students of the Manchester Grammar and Manchester High Schools. It deals with numbers such as the Riemann zeta value zeta(3)=sum_{n>0}1/n^3. Zeta values appear in the description of sunshine and of relics from the Big Bang. They also result from Feynman diagrams, which occur in the quantum field theo

Graham Denham, Mathias Schulze

We describe dualities and complexes of logarithmic forms and differentials for central affine and corresponding projective arrangements. We generalize the Borel-Serre formula from vector bundles to sheaves on projective d-space with locally free resolutions of length one. Combining these results we present a generalization of a formula due to Mustata and Sch

ETM Collaboration, Chris Michael, Andrea Shindler, Marc Wagner

We investigate the continuum limit of the low lying static-light meson spectrum using Wilson twisted mass lattice QCD with N_f = 2 dynamical quark flavours. We consider three values of the lattice spacing a ~ 0.051 fm, 0.064 fm, 0.080 fm and various values of the pion mass in the range 280 MeV < m_PS < 640 MeV. We present results in the continuum limit for l

Carl Boettiger, Jonathan Dushoff, Joshua S. Weitz

We derive an expression for the variation between parallel trajectories in phenotypic evolution, extending the well known result that predicts the mean evolutionary path in adaptive dynamics or quantitative genetics. We show how this expression gives rise to the notion of fluctuation domains - parts of the fitness landscape where the rate of evolution is ver

Jose J. Lunazzi, Daniel S. F. Magalhaes, Rolando L. Serra

In this paper we describe one setup employed for the recording of two types of holographic screens that can be used in white-light applications. We show how to obtain holographic screens with areas up to 1370 cm2 and diffraction efficiency of 17%. We analyze the holographic screens in their relevant aspects as to focal lengths, theoretical approach, sizes an

Alexander Mann, A. K. Hartmann

The solution-space structure of the 3-Satisfiability Problem (3-SAT) is studied as a function of the control parameter alpha (ratio of number of clauses to the number of variables) using numerical simulations. For this purpose, one has to sample the solution space with uniform weight. It is shown here that standard stochastic local-search (SLS) algorithms li

Ren-Min Ma, Rupert F Oulton, Volker J Sorger, Xiang Zhang

Plasmon lasers create and sustain intense and coherent optical fields below light&#39;s diffraction limit with the unique ability to drastically enhance light-matter interactions bringing fundamentally new capabilities to bio-sensing, data storage, photolithography and optical communications. However, these important applications require room temperature ope

Jihye Seo

This thesis studies meta- and exactly stable supersymmetry breaking mechanisms in heterotic and type IIB string theories and constructs an F-theory Grand Unified Theory model for neutrino physics in which neutrino mass is determined by the supersymmetry breaking mechanism. Focussing attention on heterotic string theory compactified on a 4-torus, stability of

Gennady Lyubeznik

Let k be a field, let R be a ring of polynomials in a finite number of variables over k, let D be the ring of k-linear differential operators of R and let f be a non-zero element of R. It is well-known that R_f, with its natural D-module structure, has finite length in the category of D-modules. We give a characteristic-free proof of this fact. To the best o

Ankur Moitra, Gregory Valiant

Given data drawn from a mixture of multivariate Gaussians, a basic problem is to accurately estimate the mixture parameters. We give an algorithm for this problem that has a running time, and data requirement polynomial in the dimension and the inverse of the desired accuracy, with provably minimal assumptions on the Gaussians. As simple consequences of our

Ohad Giladi, Assaf Naor

It is shown that if (X,||.||_X) is a Banach space with Rademacher type p \ge 1, then for every integer n there exists an even integer m < Cn^{2-1/p}log n (C is an absolute constant), such that for every f:Z_m^n --> X, \Avg_{x,\e}[||f(x+ m\e/2)-f(x)}||_X^p] < C(p,X) m^p\sum_{j=1}^n\Avg_x[||f(x+e_j)-f(x)||_X^p], where the expectation is with respect to uniform

Lay Nam Chang, Djordje Minic, Tatsu Takeuchi

We argue that the combination of the principles of quantum theory and general relativity allow for a dynamical energy-momentum space. We discuss the freezing of vacuum energy in such a dynamical energy-momentum space and present a phenomenologically viable seesaw formula for the cosmological constant in this context.

Gerald A. Miller

Nucleon structure is currently understood from a unified light-front, infinite-momentum-frame framework. The specific examples of the neutron transverse charge distribution and the shape of the proton are discussed here.

Ilia Gogoladze, Bin He, Qaisar Shafi

Unification at M_{GUT}\sim 3\times 10^{16} GeV of the three Standard Model (SM) gauge couplings can be achieved by postulating the existence of a pair of vectorlike fermions carrying SM charges and masses of order 300 GeV -- 1 TeV. The presence of these fermions significantly modifies the vacuum stability and perturbativity bounds on the mass of the SM Higgs

Alan P. Sexton, Richard Swinbank

The M-tree is a paged, dynamically balanced metric access method that responds gracefully to the insertion of new objects. To date, no algorithm has been published for the corresponding Delete operation. We believe this to be non-trivial because of the design of the M-tree&#39;s Insert algorithm. We propose a modification to Insert that overcomes this proble

Masamune Oguri, Masahiro Takada, Nobuhiro Okabe, Graham P. Smith

We present new measurements of dark matter distributions in 25 X-ray luminous clusters by making a full use of the two-dimensional (2D) weak lensing signals obtained from high-quality Subaru/Suprime-Cam imaging data. Our approach to directly compare the measured lensing shear pattern with elliptical model predictions allows us to extract new information on t

Jonathan L. Feng, Marc Kamionkowski, Samuel K. Lee

Light gravitinos, with mass in the eV to MeV range, are well-motivated in particle physics, but their status as dark-matter candidates is muddled by early-Universe uncertainties. We investigate how upcoming data from colliders may clarify this picture. Light gravitinos are produced primarily in the decays of the next-to-lightest supersymmetric particle, resu

V. I. Kucheryavy

By self-consistent renormalization (SCR) it is meant that all formal relations between UV-divergent Feynman amplitudes are automatically retained as well as between their regular values obtained in the framework of the SCR. The SCR is efficiently applicable on equal grounds both to renormalizable and nonrenormalizable theories. SCR furnishes new means for th

Benoit Kriegk, Michel Van den Bergh

We discuss the representation theory of the bialgebra end(A) introduced by Manin. As a side result we give a new proof that Koszul algebras are distributive and furthermore we show that some well-known N-Koszul algebras are also distributive.

B. J. Wundt, U. D. Jentschura

The theoretical treatment of Rydberg states in one-electron ions is facilitated by the virtual absence of the nuclear-size correction, and fundamental constants like the Rydberg constant may be in the reach of planned high-precision spectroscopic experiments. The dominant nuclear effect that shifts transition energies among Rydberg states therefore is due to

A. A. Gusev, O. Chuluunbaatar, V. P. Gerdt, V. A. Rostovtsev

A computation scheme for solving elliptic boundary value problems with axially symmetric confining potentials using different sets of one-parameter basis functions is presented. The efficiency of the proposed symbolic-numerical algorithms implemented in Maple is shown by examples of spheroidal quantum dot models, for which energy spectra and eigenfunctions v