April 2009 arXiv papers — page 41

J Tolar, G Chadzitaskos

Our previous work on quantum mechanics in Hilbert spaces of finite dimensions N is applied to elucidate the deep meaning of Feynman's path integral pointed out by G. Svetlichny. He speculated that the secret of the Feynman path integral may lie in the property of mutual unbiasedness of temporally proximal bases. We confirm the corresponding property of t

B. Georges, J. Grollier, V. Cros, A. Fert

We demonstrate the strong impact of the oscillator agility on the line broadening by studying spin transfer induced microwave emission in MgO-based tunnel junctions with current. The linewidth is almost not affected by decreasing the temperature. At very low currents, a strong enhancement of the linewidth at low temperature is attributed to an increase of th

Peter Grassberger

We simulate directed site percolation on two lattices with 4 spatial and 1 time-like dimensions (simple and body-centered hypercubic in space) with the standard single cluster spreading scheme. For efficiency, the code uses the same ingredients (hashing, histogram re-weighing, and improved estimators) as described in Phys. Rev. {\bf E 67}, 036101 (2003). Apa

Anis Biswas, Tapas Samanta, S. Banerjee, I. Das

Some recent experimental studies show the invisibility of antiferromagnetic transition in the cases of manganites when their particle size is reduced to nanometer scale. In complete contrast to these cases, we have observed the signature of antiferromagnetic transition in the magnetocaloric properties of nanocrystalline La$_{0.125}$Ca$_{0.875}$MnO$_{3}$ of a

Yohei Kashima

Four point correlation functions for many electrons at finite temperature in periodic lattice are analyzed by the perturbation theory with respect to the coupling constant. The correlation functions are characterized as a limit of finite dimensional Grassmann integrals. A lower bound on the radius of convergence and an upper bound on the perturbation series

Pasquale Blasi, Pasquale D. Serpico

A recently proposed model (arXiv:0903.2794) explains the rise in energy of the positron fraction measured by the PAMELA satellite in terms of hadronic production of positrons in aged supernova remnants, and acceleration therein. Here we present a preliminary calculation of the anti-proton flux produced by the same mechanism. While the model is consistent wit

Ari J. Hietanen, Kari Rummukainen, Kimmo Tuominen

We measure the evolution of the coupling constant using the Schroedinger functional method in the lattice formulation of SU(2) gauge theory with two massless Dirac fermions in the adjoint representation. We observe strong evidence for an infrared fixed point, where the theory becomes conformal. We measure the continuum beta-function and the coupling constant

Blake Winter

We consider ribbon n-knots for n\geq 2. For such knots we define a set of moves on ribbon disks, and show that any two ribbon disks for isotopic knots are related by a finite sequence of such moves and ambient isotopies. Using this we are able to prove that there is a natural geometric correspondence between ribbon n-knots and ribbon m-knots which is bijecti

Nils Carqueville

Amplitudes in open topological string theory may be described completely by certain A-infinity-categories. We detail a general construction of all cyclic minimal models for a given A-infinity-algebra and apply this result to the case of N=2 supersymmetric Landau-Ginzburg models. This allows to solve the tree-level theory in the sense that all amplitudes and

David Pritchard, Deeparnab Chakrabarty

The main focus of this paper is a pair of new approximation algorithms for certain integer programs. First, for covering integer programs {min cx: Ax >= b, 0 <= x <= d} where A has at most k nonzeroes per row, we give a k-approximation algorithm. (We assume A, b, c, d are nonnegative.) For any k >= 2 and eps>0, if P != NP this ratio cannot be improved to k-1

Christophe Arene, Tanja Lange, Michael Naehrig, Christophe Ritzenthaler

This paper proposes new explicit formulas for the doubling and addition step in Miller&#39;s algorithm to compute the Tate pairing. For Edwards curves the formulas come from a new way of seeing the arithmetic. We state the first geometric interpretation of the group law on Edwards curves by presenting the functions which arise in the addition and doubling. C

Ji-Wei Xie, Ji-Lin Zhou

Recent observations show that planet can reside in close binary systems with stellar separation of only about 20 AU. However, planet formation in such close binary systems is a challenge to current theory. One of the major theoretical problems occurs in the intermediate stage-planetesimals accretion into planetary embryos-during which the companion&#39;s per

Xiannan Li

The problem of finding upper bounds for L-functions at the edge of the critical strip has a long and interesting history. Here, the situation for classical L-functions such as Dirichlet L-functions is relatively well understood. The reason for this is because the size of the coefficients of these L-functions is known to be small. Although L-functions are gen

M. Alimohammadi, N. Olanj

Considering the most general one-species reaction-diffusion processes on a Cayley tree, it has been shown that there exist two integrable models. In the first model, the reactions are the various creation processes, i.e. $\circ\circ\to\bullet\circ$, $\circ\circ\to\bullet\bullet$ and $\circ\bullet\to\bullet\bullet$, and in the second model, only the diffusion

Atsushi Nakayashiki

The tau function corresponding to the affine ring of a certain plane algebraic curve, called (n,s)-curve, embedded in the universal Grassmann manifold is studied. It is neatly expressed by the multivariate sigma function. This expression is in turn used to prove fundamental properties on the series expansion of the sigma function established in a previous pa

Jie-Qiao Liao, Jin-Feng Huang, Yu-xi Liu, Le-Man Kuang

We propose and study an approach to realize quantum switch for single-photon transport in a coupled superconducting transmission line resonator (TLR) array with one controllable hopping interaction. We find that the single-photon with arbitrary wavevector can transport in a controllable way in this system. We also study how to realize controllable hopping in

Nefton Pali

These are lecture notes on a recent remarkable preprint of Ein-Popa, which simplifies the algebraic proof of the finite generation of the canonical ring given by the team BCHM. The Ein-Popa extension result has been translated in the analytic language by Berndson-Paun and Paun. In these notes we follow the analytic language used in Berndson-Paun and Paun. Th

Takayuki Hori

A modified version of the bilocal particle is presented in terms of complex space time. Unusual constraint structure of the model is studied, and a new concept of the physical equivalence is proposed in accordance with Dirac&#39;s conjecture. It is found that in the quantum theory the physical state conditions are compatible with existence of eigenstates of

Shohei Shimizu, Takashi Washio, Aapo Hyvarinen, Seiya Imoto

Many statistical methods have been proposed to estimate causal models in classical situations with fewer variables than observations (p<n, p: the number of variables and n: the number of observations). However, modern datasets including gene expression data need high-dimensional causal modeling in challenging situations with orders of magnitude more variable

Masaharu Ishikawa

We study compatible contact structures of fibered Seifert multilinks in homology 3-spheres and especially give a necessary and sufficient condition for the contact structure to be tight in the case where the Seifert fibration is positively twisted. As a corollary we determine the strongly quasipositivity of fibered Seifert links in the 3-sphere. We also stud

Xiaolin Luo, Pavel V. Shevchenko

An efficient adaptive direct numerical integration (DNI) algorithm is developed for computing high quantiles and conditional Value at Risk (CVaR) of compound distributions using characteristic functions. A key innovation of the numerical scheme is an effective tail integration approximation that reduces the truncation errors significantly with little extra e

Gianluca Calcagni

We study the ultraviolet complete non-relativistic theory recently proposed by Horava. After introducing a Lifshitz scalar for a general background, we analyze the cosmology of the model in Lorentzian and Euclidean signature. Vacuum solutions are found and it is argued the existence of non-singular bouncing profiles. We find a general qualitative agreement w

P. Abbamonte, J. P. Reed, Y. I. Joe, Yu Gan

Inelastic x-ray scattering (IXS) now a widely used technique for studying the dynamics of electrons in condensed matter. We previously posed a solution to the phase problem for IXS [P. Abbamonte, et. al., Phys. Rev. Lett. {\bf 92}, 237401 (2004)], that allows explicit reconstruction of the density propagator of a system. The propagator represents, physically

M. Anand, P. R. Kumar

We examine the extent to which Gaussian relay networks can be approximated by deterministic networks, and present two results, one negative and one positive. The gap between the capacities of a Gaussian relay network and a corresponding linear deterministic network can be unbounded. The key reasons are that the linear deterministic model fails to capture the

Gregory P. Dresden

It is well known that sin(aπ/b), cos(aπ/b), etc., are only rational numbers for a few select integers a and b. We show that this is equivalent to the fact that only for d = 1,2,3,4, and 6 is the primitive dth root of unity of degree 2 over Q.

Yutaka Matsumura, Hiraku Ogino, Shigeru Horii, Yukari Katsura

We have discovered new nickel-based pnictide oxide superconductors, (Ni2Pn2)(Sr4Sc2O6) (Pn = P, As). These compounds have a tetragonal unit cell with a space group of P4/nmm and they consist of alternate stacking of anti-fluorite Ni2Pn2 layers and K2NiF4-type Sr4Sc2O6 blocking layers. Lattice parameters were a = 4.044 A and c = 15.23 A for (Ni2P2)(Sr4Sc2O6)

M. Shifman, A. Yung

In N=2 supersymmetric QCD with the U(N) gauge group and N_f>N we study the crossover transition from the weak coupling regime at large ξto strong coupling at small ξwhere ξis the Fayet--Iliopoulos parameter. We find that at strong coupling a dual non-Abelian weakly coupled N=2 theory exists which describes low-energy physics at small ξ. The dual gauge group

Christopher Eltschka, Andreas Osterloh, Jens Siewert

We discuss the possibility to interpret the residual entanglement for more than three qubits in terms of distributed multipartite entanglement, or, in other words, possible extensions of the Coffman-Kundu-Wootters monogamy equality to higher qubit numbers. Existing knowledge on entanglement in multipartite systems puts narrow constraints on the form of such

Sergio del Campo, Ramon Herrera, Adolfo Toloza

The tachyonic inflationary universe model in the context of intermediate inflation is studied. General conditions for this model to be realizable are discussed. In the slow-roll approximation, we describe in great details the characteristics of this model.

F. H. Busse, R. D. Simitev

It is proposed that convection driven dynamos operating in planetary cores could be oscillatory even when the oscillations are not directly noticeable from the outside. Examples of dynamo simulations are pointed out that exhibit oscillations in the structure of the azimuthally averaged toroidal magnetic flux while the mean poloidal field shows only variation

Pierrette Cassou-Nogues, Anatoly Libgober

We describe methods for calculation of polytopes of quasiadjunction for plane curve singularities which are invariants giving a Hodge theoretical refinement of the zero sets of multivariable Alexander polynomials. In particular we identify some hyperplanes on which all polynomials in multivariable Bernstein ideal vanish.

R. T. Stebbins

The LISA science requirements and conceptual design have been fairly stable for over a decade. In the interest of reducing costs, the LISA Project at NASA has looked for simplifications of the architecture, at downsizing of subsystems, and at descopes of the entire mission. This is a natural activity of the formulation phase, and one that is particularly tim

Sadok Kallel

We discuss various aspects of `braid spaces&#39; or configuration spaces of unordered points on manifolds. First we describe how the homology of these spaces is affected by puncturing the underlying manifold, hence extending some results of Fred Cohen, Goryunov and Napolitano. Next we obtain a precise bound for the cohomological dimension of braid spaces. Th

Masaaki Yoshida

In the paper `Automorphic functions for a Whitehead-complement group&#39;, [Osaka J Math 43 (2006) 63-77] Matsumoto, Nishi and Yoshida constructed automorphic functions on real 3-dimensional hyperbolic space for a Kleinian group called the Whitehead-link-complement group. For a Kleinian group (of the first kind), no automorphic function/form has been studied

Akira Arai, Makoto Uemura, Mahito Sasada, Sergei A. Trushkin

We report detailed, long term near-infrared (NIR) light curves of GRS 1915+105 in 2007-2008, covering its long &#34;soft state&#34; for the first time. From our NIR monitoring and the X-ray data of the All Sky Monitor (ASM) onboard Rossi X-ray Timing Explorer (RXTE), we discovered that the NIR flux dropped by > 1 mag during short X-ray flares with a time-sca

J. Froehlich, M. Griesemer, I. M. Sigal

We prove the limiting absorption principle for the standard model of the non-relativistic quantum electrodynamics (QED) and for the Nelson model describing interactions of electrons with phonons. To this end we use the spectral renormalization group technique on the continuous spectrum in conjunction with the Mourre theory.

Fridolin Roth

We calculate the Lusternik-Schnirelmann category of the k-th ordered configuration spaces F(R^n,k) of R^n and give bounds for the category of the corresponding unordered configuration spaces B(R^n,k) and the sectional category of the fibrations pi^n_k: F(R^n,k) --> B(R^n,k). We show that secat(pi^n_k) can be expressed in terms of subspace category. In many c

Igor R. Klebanov, Silviu S. Pufu, Fabio D. Rocha

We use direct Kaluza-Klein reduction to calculate the spectrum of spin-2 modes around a warped product of AdS_4 and a certain squashed and stretched 7-sphere. The modes turn out to be polynomials in the four complex variables parameterizing the sphere, and their complex conjugates. The background, which possesses U(1)_R x SU(3) symmetry, has been conjectured

Michael E. Anderson, Joel N. Bregman, Suzanne C. Butler, C. R. Mullis

Clusters of galaxies provide a closed box within which one can determine the chemical evolution of the gaseous baryons with cosmic time. We studied this metallicity evolution in the hot X-ray emitting baryons through an analysis of XMM-Newton observations of 29 galaxy clusters in the redshift range 0.3 < z < 1.3. Taken alone, this data set does not show evid

Juno Mukai

The present paper gives a proof of the author&#39;s paper in the Proceeding of the International Conference on Homotopy Theory and Related Topics at Korea University (2005), 109--113, on the orders of Whitehead products of iota_n with alpha in pi^n_{n+k}, (n > k+1, k < 25) and improves and extends it. The method is to use composition methods in the homotopy

Margarida Mendes Lopes, Rita Pardini

Let S be a smooth minimal complex projective surface of maximal Albanese dimension. Under the assumption that the canonical class of S is ample and the irregularity of S, q(S), is greater or equal to 5 we show that K^2>= 4χ(S)+(10/3)q(S)-8, thus improving the well known Severi inequality K^2>=4χ(S). We also give stronger inequalities under extra assumptions

Wolfgang Bein, Leah Epstein, Lawrence L. Larmore, John Noga

We consider the online list s-batch problem, where all the jobs have processing time 1 and we seek to minimize the sum of the completion times of the jobs. We give a Java program which is used to verify that the competitiveness of this problem is 619/583.

Luis C. B. Crispino, Sam R. Dolan, Ednilton S. Oliveira

We present a study of scattering of massless planar scalar waves by a charged non-rotating black hole. Partial wave methods are applied to compute scattering and absorption cross sections, for a range of incident wavelengths. We compare our numerical results with semi-classical approximations from a geodesic analysis, and find excellent agreement. The glory

Evghenii Gaburov, James Lombardi, Simon Portegies Zwart

The onset of runaway stellar collisions in young star clusters is more likely to initiate with an encounter between a binary and a third star than between two single stars. Using the initial conditions of such three-star encounters from direct $N$-body simulations, we model the resulting interaction by means of Smoothed Particle Hydrodynamics (SPH). We find

D. R. Ballantyne

A X-ray background synthesis model is used to calculate the contribution of Active Galactic Nuclei (AGNs) to the 1.4 GHz number counts between 100 nJy and 10 mJy. The number counts are broken down into contributions from radio-quiet and radio-loud AGNs, obscured and unobscured AGNs, and for different ranges in redshift and 2-10 keV X-ray luminosity, L_X. Com

Weiyu Xu, M. Amin Khajehnejad, Salman Avestimehr, Babak Hassibi

It is now well understood that $\ell_1$ minimization algorithm is able to recover sparse signals from incomplete measurements [2], [1], [3] and sharp recoverable sparsity thresholds have also been obtained for the $\ell_1$ minimization algorithm. However, even though iterative reweighted $\ell_1$ minimization algorithms or related algorithms have been empiri

J. Zemen, J. Kucera, K. Olejnik, T. Jungwirth

We present a theoretical survey of magnetocrystalline anisotropies in (Ga,Mn)As epilayers and compare the calculations to available experimental data. Our model is based on an envelope function description of the valence band holes and a spin representation for their kinetic-exchange interaction with localised electrons on Mn ions, treated in the mean-field

Douglas Henderson

It is well known that equilibrium in a thermodynamic system results from a competition or balance between lowering the energy and increasing the entropy, or at least the product of the temperature and entropy. This is remarkably similar to the Taoist concept of yin, a downward influence, and yang, an upward influence, where harmony is established by balancin

M. Angeles Perez-Garcia, J. Navarro, A. Polls

Landau&#39;s Fermi Liquid parameters are calculated for non-superfluid pure neutron matter in the presence of a strong magnetic field at zero temperature. The particle-hole interactions in the system, where a net magnetization may be present, are characterized by these parameters in the framework of a multipolar formalism. We use either zero- or finite-range

Sahbi Sidhom

In the era of the information society, the impact of the information systems on the economy of material and immaterial is certainly perceptible. With regards to the information resources of an organization, the annotation involved to enrich informational content, to track the intellectual activities on a document and to set the added value on information for

Roy A. Briere

Precision results on the leptonic, semileptonic, and hadronic decays of charm mesons are reviewed. These results are important for timely progress in weak flavor physics both in their own right and as checks of theoretical calculations. Recent years have seen much progress on weak decays of charm, in both theory and experiment, a trend we expect to continue.

L. Vostrikova

In exponential semi-martingale setting for risky asset we estimate the difference of prices of options when initial physical measure $P$ and corresponding martingale measure $Q$ change to $\tilde{P}$ and $\tilde{Q}$ respectively. Then, we estimate $L_1$-distance of option&#39;s prices for corresponding parametric models with known and estimated parameters. T

P. -E. Tremblay, P. Bergeron, J. Dupuis

We present new calculations for the Stark broadening of the hydrogen line profiles in the dense atmospheres of white dwarf stars. Our improved model is based on the unified theory of Stark broadening from Vidal, Cooper & Smith, but it also includes non-ideal gas effects from the Hummer & Mihalas occupation probability formalism directly inside the line profi

S. Alexakis, A. D. Ionescu, S. Klainerman

We prove that a regular stationary black-hole solution of the Einstein vacuum equations which is &#34;close&#34; to some Kerr solution is, in fact, isometric to that Kerr solution.

F. G. Alvarenga, A. B. Batista, J. C. Fabris, M. J. S. Houndjo

The effect of quantum particle production near the big rip singularity has been investigated previously, with the conclusion that the energy of the produced particle decreases as the future singularity is approached. Hence, the effect of particle production would not be effective to avoid the big rip singularity. That calculation was performed by introducing

Guy Freeman, Jim Q. Smith

The class of chain event graph models is a generalisation of the class of discrete Bayesian networks, retaining most of the structural advantages of the Bayesian network for model interrogation, propagation and learning, while more naturally encoding asymmetric state spaces and the order in which events happen. In this paper we demonstrate how with complete

Martin Eckstein, Marcus Kollar, Philipp Werner

We use non-equilibrium dynamical mean-field theory to demonstrate the existence of a critical interaction in the real-time dynamics of the Hubbard model after an interaction quench. The critical point is characterized by fast thermalization and separates weak-coupling and strong-coupling regimes in which the relaxation is delayed due to prethermalization on

Huaiyu Duan, James P Kneller

Rapid progress has been made during recent years in the understanding of the flavour oscillations that occur as neutrinos traverse through supernova. The previous paradigm has given way and it is now clear that the neutrino signals we shall receive from future Galactic supernovae will allow us both to peer inside these extraordinary cosmic events and to prob

Oleg I. Berngardt, Alexander P. Potekhin

In the paper within the approximation of the two-fluid magnetohydrodynamics and geometrooptical approximation the dispersion relation was found for ionacoustic instabilities of the ionospheric plasma at 80-200km altitudes in three-dimensional weakly irregular ionosphere. Low freqeuncy solution was found. The difference between obtained and standard solution

Stanislav Popovych

The Spectral Problem is to describe possible spectra $σ(A_j)$ for an irreducible $n$-tuple of Hermitian operators s.t. $A_1+...+A_n$ is a scalar operator. In case when $m_j= | σ(A_j)|$ are finite and a rooted tree ${\rm T}_{m_1,..., m_n}$ with $n$ branches of lengths $m_1, ..., m_n$ is a Dynkin graph the explicit answer to the Spectral Problem was given rece

Leonardo Zapponi

Belyi&#39;s theorem asserts that a smooth projective curve $X$ defined over a number field can be realized as a cover of the projective line unramified outside three points. In this short paper we investigate the bejaviour of the minimal degree of such a cover. More precisely, we start by defining the absolute Belyi degree of X, which only depends on the $\b

Michael Shao, Geoff Marcy, Joseph H. Catanzarite, Stephen J. Edberg

Astrometry can detect rocky planets in a broad range of masses and orbital distances and measure their masses and three-dimensional orbital parameters, including eccentricity and inclination, to provide the properties of terrestrial planets. The masses of both the new planets and the known gas giants can be measured unambiguously, allowing a direct calculati

F. Vallini, D. S. L Figueira, P. F. Jarschel, L. A. M. Barea

InGaAsP/InP quantum wells (QW) ridge waveguide lasers were fabricated for the evaluation of Ga+ Focused Ion Beam (FIB) milling of mirrors. Electrical and optical proprieties were investigated. A 7% increment in threshold current, a 17% reduction in external quantum efficiency and 15 nm blue shift in the emission spectrum were observed after milling as compar

Amelia Sparavigna

Dipole and higher moments are physical quantities used to describe a charge distribution. In analogy with electromagnetism, it is possible to define the dipole moments for a gray-scale image, according to the single aspect of a gray-tone map. In this paper we define the color dipole moments for color images. For color maps in fact, we have three aspects, the

Xin-Zhong Yan, C. S. Ting

With a conserving formalism within the self-consistent Born approximation, we study the Hall conductivity of Dirac fermions in graphene under charged impurity scatterings. The calculated inverse Hall coefficient is compared with the experimental data. It is shown that the present calculations for the Hall coefficient and the electric conductivity are in good

GianCarlo Ghirardi

We reconsider some important foundational problems of quantum mechanics. After reviewing the measurement problem and discussing its unavoidability, we analyze some proposals to overcome it. This analysis leads us to reconsider the current debate on our best theory, i.e. quantum mechanics itself. We stress that, after the remarkable interest and the many effo

Vincenzo Cirigliano, Ryuichiro Kitano, Yasuhiro Okada, Paula Tuzon

We assess the model discriminating power of a combined phenomenological analysis of mu -> e gamma and mu -> e conversion on different target nuclei, including the current hadronic uncertainties. We find that the theoretical uncertainties can be largely reduced by using input from lattice QCD and do not constitute a limiting factor in discriminating models wh

Yaakov S. Weinstein

I explore entanglement dynamics in examples of quantum memories, decoherence free subspaces (DFS) and noiseless subsystems (NS), to determine how a complete loss of entanglement affects the ability of these techniques to protect quantum information. Using negativity and concurrence as entanglement measures, I find that in general there is no correlation betw

Johannes Schmude

One of the main problems in the search for string duals with backreacting, smeared flavors is the construction of a suitable source density. We review how this issue may be addressed using generalized calibrated geometry.

E. M. C. Abreu, L. P. G. De Assis, C. M. L. dos Reis

The accelerated expansion of the universe has now been confirmed by several independent observations including those of high redshift type Ia supernovae, and the cosmic microwave background combined with the large scale structure of the Universe. In this work we introduce families of analytical solutions for the scale factor different from the current litera

Fabio Bonaretti, Daniele Faccio, Matteo Clerici, Jens Biegert

We propose a new experimental technique, which allows for a complete characterization of ultrashort optical pulses both in space and in time. Combining the well-known Frequency-Resolved-Optical-Gating technique for the retrieval of the temporal profile of the pulse with a measurement of the near-field made with an Hartmann-Shack sensor, we are able to retrie

Dongsheng Wu, Yimin Xiao

Let $B^{α_i}$ be an $(N_i,d)$-fractional Brownian motion with Hurst index ${α_i}$ ($i=1,2$), and let $B^{α_1}$ and $B^{α_2}$ be independent. We prove that, if $\frac{N_1}{α_1}+\frac{N_2}{α_2}>d$, then the intersection local times of $B^{α_1}$ and $B^{α_2}$ exist, and have a continuous version. We also establish Hölder conditions for the intersection local ti

A. J. M. Giesbers, L. A. Ponomarenko, K. S. Novoselov, A. K. Geim

We have measured a strong increase of the low-temperature resistivity $\rho_{xx}$ and a zero-value plateau in the Hall conductivity $\sigma_{xy}$ at the charge neutrality point in graphene subjected to high magnetic fields up to 30 T. We explain our results by a simple model involving a field dependent splitting of the lowest Landau level of the order of a f

M. N. Chernodub, Atsushi Nakamura, V. I. Zakharov

We summarize and extend evidence that the deconfinement phase transition in Yang-Mills theories can be viewed as change of effective non-perturbative degrees of freedom and of symmetries of their interactions. In short, the strings in four dimensions (4d) at temperatures below the critical temperature Tc are replaced by particles, or field theories in 3d at

Jerome Faillettaz, Didier Sornette, Martin Funk

We model the progressive maturation of a heterogeneous mass towards a gravity-driven instability, characterized by the competition between frictional sliding and tension cracking, using array of slider blocks on an inclined basal surface, which interact via elastic-brittle springs. A realistic state- and rate-dependent friction law describes the block-surfac

Romain Pierrat, Benoit Gremaud, Dominique Delande

We present a transport equation for the incoherent propagation of radiation inside a quasi-resonant atomic gas at low temperature. The derivation is based on a generalized Bethe-Salpeter equation taking into account the motion of the atoms. The obtained equation is similar to the radiative transfer equation. It is solved numerically by an original Monte Carl

F. Ferlaino, S. Knoop, M. Berninger, M. Mark

We study collisions in an optically trapped, pure sample of ultracold Cs$_2$ molecules in various internal states. The molecular gas is created by Feshbach association from a near-degenerate atomic gas, with adjustable temperatures in the nanokelvin range. We identify several narrow loss resonances, which point to the coupling to more complex molecular state

S. Saito, T. Tilma, S. J. Devitt, K. Nemoto

In this paper we present an experimentally realizable microwave pulse sequence that effects a Controlled NOT (C-NOT) gate operation on a Josephson junction-based flux-qubit/resonator system with high fidelity in the end state. We obtained a C-NOT gate process fidelity of 0.988 (0.980) for a two (three) qubit/resonator system under ideal conditions, and a fid

GianCarlo Ghirardi, Karl Wienand

In this paper, following an elementary line of thought which somewhat differs from the usual one, we prove once more that any deterministic theory predictively equivalent to quantum mechanics unavoidably exhibits a contextual character. The purpose of adopting this perspective is that of paving the way for a critical analysis of the use of counterfactual arg

Mamoru Mimura, Kei Sugata

We determine the Lusternik-Schnirelmann category of the irreducible, symmetric Riemann spaces SU(n)/SO(n) and SU(2n)/Sp(n) of type AI and AII respectively.

Chadi Taher

We calculate the parabolic Chern character of a bundle with locally abelian parabolic structure on a smooth strict normal crossings divisor, using the definition in terms of Deligne-Mumford stacks. We obtain explicit formulas for $ch_1$, $ch_2$ and $ch_3$, and verify that these correspond to the formulas given by Borne for $ch_1$ and Mochizuki for $ch_2$.

Eddy Godelle

We provide every Renner monoids with a monoid presentation, and we introduce a length function which extends the Coxeter length function.

Thilo Hannemann, Christof Wunderlich, Martin Plesch, Mario Ziman

We report experimental implementation of various types of qubit channels using an individual trapped ion. We analyzed experimental data and we performed tomographic reconstruction of quantum channels based on these data. Specifically, we studied phase damping channels, where the damping acts either in the xy-plane of the Bloch sphere or in an arbitrary plane

Manuel Masip, Iacopo Mastromatteo

We discuss possible implications of a large interaction cross section between cosmic rays and dark matter particles due to new physics at the TeV scale. In particular, in models with extra dimensions and a low fundamental scale of gravity the cross section grows very fast at transplanckian energies. We argue that the knee observed in the cosmic ray flux coul

P. Marquard, J. H. Piclum, D. Seidel, M. Steinhauser

We evaluate the corrections to the matching coefficient of the vector current between Quantum Chromodynamics (QCD) and Non-Relativistic QCD (NRQCD) to three-loop order containing a closed heavy-fermion loop. The result constitutes a building block both for the bottom- and top-quark system at threshold. Strong emphasis is put on our completely automated appro

Paweł Caban, Jakub Rembieliński, Marta Włodarczyk

We show that configurations exist in which the correlation functions and the degree of violation of Bell-type inequalities in the relativistic Einstein-Podolsky-Rosen (EPR) experiment have local extrema for some values of the velocities of the EPR particles. Moreover, this strange behavior can be observed for both discussed relativistic spin operators and fo

G. P. Guo, Y. J. Zhao, T. Tu, X. J. Hao

Resistively Detected Nuclear Magnetic Resonance (RD-NMR) has been used to investigate a two-subband electron system in a regime where quantum Hall pseudo-spin ferromagnetic (QHPF) states are prominently developed. It reveals that the easy-axis QHPF state around the total filling factor $ν=4 $ can be detected by the RD-NMR measurement. Approaching one of the

Wim Cosyn, Jan Ryckebusch

We consider high-energy quasifree single- and two-proton knockout reactions induced by electrons and protons and address the question what target-nucleus densities can be effectively probed after correcting for nuclear attenuation (initial- and final-state interactions). Our calculations refer to ejected proton kinetic energies of 1.5 GeV, the reactions (e,e

Marek A. Abramowicz

Paczynski realized that a properly chosen gravitational potential may accurately model (in a &#34;pseudo Newtonian&#34; theory) general relativistic effects that determine motion of matter near a non-rotating black hole. Paczynski&#39;s choice, known today as the &#34;Paczynski-Wiita potential&#34;, proved to be very practical. It was used by numerous resear

Pavel Shvartsman

We describe a class of Sobolev $W^k_p$-extension domains $Ω\subset R^n$ determined by a certain inner subhyperbolic metric in $Ω$. This enables us to characterize finitely connected Sobolev $W^1_p$-extension domains in $R^2$ for each $p>2$.

Dinesh Khurana

Grinshpon has proved that if $S$ is a commutative subring of a ring $R$ and $A\in M_n(S)$ is invertible in $M_n(R)$, then $det(A)$ is invertible in $R$. We give a very short proof of the result.

Niklas Teichmann, Dennis Hinrichs, Martin Holthaus, Andre Eckardt

We carry out a perturbative analysis, of high order in the tunneling parameter, of the ground state of the homogeneous Bose-Hubbard model in the Mott insulator phase. This is made possible by a diagrammatic process chain approach, derived from Kato&#39;s representation of the many-body perturbation series, which can be implemented numerically in a straightfo

F. -Q. Xie, R. Maul, A. Augenstein, Ch. Obermair

The controlled fabrication of actively switchable atomic-scale devices, in particular transistors, has remained elusive to date. Here we explain operation of an atomic-scale three-terminal device by a novel switching mechanism of bistable, self-stabilizing reconstruction of the electrode contacts at the atomic level: While the device is manufactured by elect

Krzysztof Pawlikowski, Andrzej Pȩkalski

Role of range of interactions in a model of charged particles diffusing on a two-dimensional lattice is studied. We investigate, via Monte Carlo simulations, three models. In the first one interactions are restricted to nearest neighbors, in the second one we add (weaker) interactions to second nearest neighbors. In the third model interactions are extended

Catalin Zara

For a flag manifold $M=G/B$ with the canonical torus action, the $T-$equivariant cohomology is generated by equivariant Schubert classes, with one class $τ_u$ for every element $u$ of the Weyl group $W$. These classes are determined by their restrictions to the fixed point set $M^T \simeq W$, and the restrictions are polynomials with nonnegative integer coef

M. Gurses, A. Karasu, R. Turhan

We construct the recursion operators for the non-commutative Burgers equations using their Lax operators. We investigate the existence of any integrable mixed version of left- and right-handed Burgers equations on higher symmetry grounds.

Christian Böhning

This is a survey of the rationality problem in invariant theory. It also contains some new results, in particular in Chapter 2 on moduli spaces of plane curves with a theta-characteristic, and a detailed account of the relation of the Hesselink stratification of the Hilbert nullcone to the rationality problem, with an application to the rationality of the mo

F. Bagarello

In this paper we show how to construct a certain class of orthonormal bases in $L^2({\bf R}^d)$ starting from one or more Gabor orthonormal bases in $L^2({\bf R})$. Each such basis can be obtained acting on a single function $Ψ(\underline x)\in L^2({\bf R}^d)$ with a set of unitary operators which operate as translation and modulation operators {\em in suita

N. Shukla, G. Brodin, M. Marklund, P. K. Shukla

By using the quantum hydrodynamic and Maxwell equations, we derive nonlinear electron-magnetohydrodynamic (MHD), Hall-MHD, and dust Hall-MHD equations for dense quantum magnetoplasmas. The nonlinear equations include the electromagnetic, the electron pressure gradient, as well as the quantum electron tunneling and electron spin forces. They are useful for in

F. Bagarello

We propose and discuss some toy models of stock markets using the same operatorial approach adopted in quantum mechanics. Our models are suggested by the discrete nature of the number of shares and of the cash which are exchanged in a real market, and by the existence of conserved quantities, like the total number of shares or some linear combination of cash