June 2004 arXiv papers — page 8
Showing 701–800 of 3,692 papers
J. J. Blanco-Pillado, C. P. Burgess, J. M. Cline, C. Escoda
We develop a model of eternal topological inflation using a racetrack potential within the context of type IIB string theory with KKLT volume stabilization. The inflaton field is the imaginary part of the Kähler structure modulus, which is an axion-like field in the 4D effective field theory. This model does not require moving branes, and in this sense it is
Pavel Etingof
This paper is an expanded and updated version of the preprint arXiv:math/0406499. It includes a more detailed description of the basics of the theory of Cherednik and Hecke algebras of varieties started in arXiv:math/0406499, as well as a new Section 4, which reviews the developments in this theory since 2004 with references to the relevant literature. Let $
Edwin Langmann
We present further remarkable functional identities related to the elliptic Calogero-Sutherland (eCS) system. We derive them from a second quantization of the eCS model within a quantum field theory model of anyons on a circle and at finite temperature. The identities involve two eCS Hamiltonians with arbitrary and, in general, different particle numbers $N$
Gabrijela Zaharijas, Glennys R. Farrar
We consider the cross section limits for light dark matter candidates ($m=0.4$ to 10 GeV). We calculate the interaction of dark matter in the crust above underground dark matter detectors and find that in the intermediate cross section range, the energy loss of dark matter is sufficient to fall below the energy threshold of current underground experiments. T
Statistical features of 21-cm emission from the epoch between reionization and Gunn-Peterson transparency
astro-phPing He, Jiren Liu, Long-Long Feng, Hong-Guang Bi
We investigate the 21 cm emission from the epoch between reionization z_r and Gunn-Peterson transparency z_{gp}. According to the lognormal model of the thermal history around reionization, hydrogen clouds in z_r > z > z_{gp} are hot and a predominant part of baryonic gas is ionized, but still opaque to Ly-alpha photons. Therefore, 21 cm emission is a distin
M. Adell, V. Stanciu, J. Kanski, L. Ilver
We demonstrate that in situ post-growth annealing of GaMnAs layers under As capping is adequate for achieving high Curie temperatures (Tc) in a similar way as ex situ annealing in air or in N2 atmosphere practiced earlier.
L. A. Ferreira
We introduce a Skyrme type, four dimensional Euclidean field theory made of a triplet of scalar fields n, taking values on the sphere S^2, and an additional real scalar field phi, which is dynamical only on a three dimensional surface embedded in R^4. Using a special ansatz we reduce the 4d non-linear equations of motion into linear ordinary differential equ
S. Katz, E. Sharpe
In this paper we shall describe some correlation function computations in perturbative heterotic strings that, for example, in certain circumstances can lend themselves to a heterotic generalization of quantum cohomology calculations. Ordinary quantum chiral rings reflect worldsheet instanton corrections to correlation functions involving products of Dolbeau
Viktor Bengtsson, Martin Cederwall, Henric Larsson, Bengt E. W. Nilsson
We outline a formulation of membrane dynamics in D=8 which is fully covariant under the U-duality group SL(2,Z) x SL(3,Z), and encodes all interactions to fields in the eight-dimensional supergravity, which is constructed through Kaluza-Klein reduction on T^3. Among the membrane degrees of freedom is an SL(2,R) doublet of world-volume 2-form potentials, whos
S. Dobashi, T. Yoneya
The issue of holographic mapping between bulk and boundary in the plane-wave limit of AdS/SYM correspondence is reexamined from the viewpoint of correlation functions. We first study the limit of large angular momentum for the so-called GKP-W relation in supergeravity approximation, connecting directly the effective action in the bulk and the generating func
Alexander D. Popov, Martin Wolf
It was recently shown by Witten on the basis of several examples that the topological B-model whose target space is a Calabi-Yau (CY) supermanifold is equivalent to holomorphic Chern-Simons (hCS) theory on the same supermanifold. Moreover, for the supertwistor space CP^{3|4} as target space, it has been demonstrated that hCS theory on CP^{3|4} is equivalent
D. Michielsen, S. De Rijcke, W. W. Zeilinger, P. Prugniel
We present R-band and H-alpha+[N II] narrow-band imaging of FCC032, FCC206 and FCCB729, three dwarf elliptical galaxies (dEs) in the Fornax Cluster. These dEs contain significant amounts of ionized gas. FCC032 harbours a large ionized gas complex, consisting of several individual clouds, a superbubble and a filament that extends away from the galaxy centre.
Z. Y. Zhou, G. Y. Qin, P. Zhang, Z. G. Xiao
The pole structure of the low energy $ππ$ scattering amplitudes is studied using a proper chiral unitarization method combined with crossing symmetry and the low energy phase shift data. It is found that the $σ$ pole position is at $M_σ=470\pm 50MeV$, $Γ_σ=570\pm 50MeV$. The existence of the virtual state pole in the IJ=20 channel is reconfirmed. Various thr
M. Tafalla, J. Santiago, D. Johnstone, R. Bachiller
We present the first case of a highly collimated, extremely high velocity bipolar outflow in Taurus. It is powered by the low-luminosity (0.4 L_sun) source IRAS 04166+2706 and contains gas accelerated up to 50 km/s with respect to the ambient cloud both toward the blue and the red (uncorrected for projection). At the highest velocities, the outflow collimati
Sergio Dain
For a given asymptotically flat initial data set for Einstein equations a new geometric invariant is constructed. This invariant measure the departure of the data set from the stationary regime, it vanishes if and only if the data is stationary. In vacuum, it can be interpreted as a measure of the total amount of radiation contained in the data.
V. K. Onemli, R. P. Woodard
We report on a revision of our previous computation of the renormalized expectation value of the stress-energy tensor of a massless, minimally coupled scalar with a quartic self-interaction on a locally de Sitter background. This model is important because it demonstrates that quantum effects can lead to violations of the weak energy condition on cosmologica
Manuel Calixto, Julio Guerrero
We present a unified group-theoretical derivation of the Continuous Wavelet Transform (CWT) on the circle $\mathbb S^1$ and the real line $\mathbb{R}$, following the general formalism of Coherent States (CS) associated to unitary square integrable (modulo a subgroup, possibly) representations of the group $SL(2,\mathbb{R})$. A general procedure for obtaining
Y. -J. Lee, M. -Z. Wang
We report the first observation of the charmless hyperonic B decay, B^+ --> Lambda Lambdabar K^+, using a 140 fb^-1 data sample recorded at the Upsilon(4S) resonance with the Belle detector at the KEKB e^+e^- collider. The measured branching fraction is B(B^+ --> Lambda Lambdabar K^+) = 2.91 ^{+0.90}_{-0.70} +/- 0.38 *10^-6 . We also perform a search for the
Belle Collaboration
We present a measurement of the unitarity triangle angle phi_3 using a Dalitz plot analysis of the three-body decay of the neutral D meson from the B->D(*)K process. The method employs the interference between D0 and D0bar to extract both the weak and strong phases. We apply this method to a 140 fb^{-1} data sample collected by the Belle experiment. The anal
M. Bauer, G. Girardi, R. Stora, F. Thuillier
We review definitions of generalized parallel transports in terms of Cheeger-Simons differential characters. Integration formulae are given in terms of Deligne-Beilinson cohomology classes. These representations of parallel transport can be extended to situations involving distributions as is appropriate in the context of quantized fields.
Elephants can always remember: Exact long-range memory effects in a non-Markovian random walk
cond-mat.stat-mechGunter M. Schütz, Steffen Trimper
We consider a discrete-time random walk where the random increment at time step $t$ depends on the full history of the process. We calculate exactly the mean and variance of the position and discuss its dependence on the initial condition and on the memory parameter $p$. At a critical value $p_c^{(1)}=1/2$ where memory effects vanish there is a transition fr
Karl Landsteiner
Generalized Konishi anomaly relations in the chiral ring of N=1 supersymmetric gauge theories with unitary gauge group and chiral matter field in two-index tensor representations are derived. Contrary to previous investigations of related models we do not include matter multiplets in the adjoint representation. The corresponding curves turn out to be hyperel
The Maxwell--Boltzmann gas with non-standard self--interactions: a novel approach to galactic dark matter
astro-phAlexander Balakin, Roberto A. Sussman, Winfried Zimdahl
Using relativistic kinetic theory, we study spherically symmetric, static equilibrium configurations of a collisionless Maxwell-Boltzmann gas with non-standard self-interactions, modelled by an effective one--particle force. The resulting set of equilibrium conditions represents a generalization of the classical Tolman-Oppenheimer-Volkov equations. We specif
Bo Feng, Hong Li, Mingzhe Li, Xinmin Zhang
We study the phenomenologies in astrophysics and particularly in CMB associated with the gravitational leptogenesis. Our results show that future CMB polarization experiments, such as PLANCK and CMBpol will make a possible test on this class of model for leptogenesis.
Benoît Grémaud
Real atomic systems, like the hydrogen atom in a magnetic field or the helium atom, whose classical dynamics are chaotic, generally present both discrete and continuous symmetries. In this letter, we explain how these properties must be taken into account in order to obtain the proper (i.e. symmetry projected) $\hbar$ expansion of semiclassical expressions l
Wan-lei Guo
In the framework of type II seesaw mechanism we propose two simple but instructive ansatze for neutrino mixing and leptogenesis. In each ansatz, the effective Majorana neutrino mass matrix is composed of two parts -- the part with Z_2 symmetry arises from the ordinary type I seesaw mechanism and the part with S_3 symmetry arises from an additional Higgs trip
Subodh P Patil
We wish to consider in this report the large N limit of a particular matrix model introduced by Myers describing D-brane physics in the presence of an RR flux background. At finite N, fuzzy spheres appear naturally as non-trivial solutions to this matrix model and have been extensively studied. In this report, we wish to demonstrate several new classes of so
G. Seibold, J. Lorenzana
Within the time-dependent Gutzwiller approximation for the Hubbard model we compute the magnetic fluctuations of vertical metallic stripes with parameters appropriate for La$_{1.875}$Ba$_{0.125}$CuO$_4$ (LBCO). For bond- and site-centered stripes the excitation spectra are similar, consisting of a low-energy incommensurate acoustic branch which merges into a
Aaron Bergman, Uday Varadarajan
We show that the data of a principal G-bundle over a principal circle bundle is equivalent to that of a \hat{LG} = U(1) |x LG bundle over the base of the circle bundle. We apply this to the Kaluza-Klein reduction of M-theory to IIA and show that certain generalized characteristic classes of the loop group bundle encode the Bianchi identities of the antisymme
K. Farakos, P. Pasipoularides
We calculate the one loop effective potential for a 5D SU(2) gauge field theory at finite temperature $T=1/β$ and radius R=1/M. This calculation is performed, for the first time, in the case of background fields with two constant components $A^{3}_{y}$ (directed towards the compact extra dimension with radius R) and $A^{3}_τ$ (directed towards the compact Eu
Economically Improving Message-Unilaterally-Transmitted Quantum Secure Direct Communication to Realize Two-Way Communication
quant-phZhan-jun Zhang, Zhong-xiao Man, Yong Li
We present a subtle idea to economically improve message-unilaterally-transmitted quantum secure direct communication (QSDC) protocols to realize two-way secure direct communication.
The average detection probability of the quantum dialogue protocol under the disturbance attack is 3/4
quant-phNguyen Ba An
We prove explicitly that the detection probability of the disturbance attack in the recently proposed quantum dialogue protocol is 3/4 in average. The purpose is not only to reply a comment but also to provide a deeper understanding of a kind of tampering in an unauthorized communication.
Janus H. Wesenberg, Klaus Molmer
We determine the probability distribution for the field inside a random uniform distribution of electric or magnetic dipoles. For parallel dipoles, simulations and an analytical derivation show that although the average contribution from any spherical shell around the probe position vanishes, the Levy stable distribution of the field is symmetric around a no
Alexander Yu. Vlasov
In recent work [quant-ph/0405174] by Schumacher and Werner was discussed an abstract algebraic approach to a model of reversible quantum cellular automata (CA) on a lattice. It was used special model of CA based on partitioning scheme and so there is a question about quantum CA derived from more general, standard model of classical CA. In present work is con
Xin Lü, Deng-Guo Feng
A quantum digital signature protocol based on quantum mechanics is proposed in this paper. The security of the protocol relies on the existence of quantum one-way functions by quantum information theorem. This protocol involves a so-called arbitrator who validates and authenticates the signed message. In this protocol, we use privacy key algorithm to ensure
Ludwik Turko
We give a physical notion to all self-adjoint extensions of the operator $id/dx$ in the finite interval. It appears that these extensions realize different non-unitary equivalent representations of CCR and are related to the momentum operator viewed from different inertial systems. This leads to the generalization of Galilei equivalence principle and gives a
S. Nicolosi, A. Napoli, A. Messina
The exact dynamics of $N$ two-level atoms coupled to a common electromagnetic bath and closely located inside a lossy cavity is reported. Stationary radiation trapping effects are found and very transparently interpreted in the context of our approach. We prove that initially injecting one excitation only in the $N$ atoms-cavity system, loss mechanisms asymp
Jin-Yuan Hsieh, Che-Ming Li, Der-San Chuu
As the matching condition in Grover search algorithm is transgressed due to inevitable errors in phase inversions, it gives a reduction in maximum probability of success. With a given degree of maximum success, we have derive the generalized and imroved criterion for tolerated error and corresponding size of quantum database under the inevitable gate imperfe
Elchanan Mossel, Mike Steel
In this paper we review some recent results that shed light on a fundamental question in molecular systematics: how much phylogenetic `signal' can we expect from characters that have evolved under some Markov process? There are many sides to this question and we begin by describing some explicit bounds on the probability of correctly reconstructing an an
I. C. Baianu, P. R. Lozano, V. I. Prisecaru, H. C. Lin
Selected applications of novel techniques in Agricultural Biotechnology, Health Food formulations and Medical Biotechnology are being reviewed with the aim of unraveling future developments and policy changes that are likely to open new niches for Biotechnology and prevent the shrinking or closing the existing ones. Amongst the selected novel techniques with
V. I. Prisecaru, I. C. Baianu
A new approach to the modular, complex systems analysis of nonlinear dynamics in cell cycling network transformations involved in carcinogenesis is proposed. Carcinogenesis is a complex process that involves dynamically inter-connected biomolecules in the intercellular, membrane, cytosolic, nuclear and nucleolar compartments that form numerous inter-related
Roger Barlow
Asymmetric statistical errors arise for experimental results obtained by Maximum Likelihood estimation, in cases where the number of results is finite and the log likelihood function is not a symmetric parabola. This note discusses how separate asymmetric errors on a single result should be combined, and how several results with asymmetric errors should be c
Frictional sliding modes along an interface between identical elastic plates subject to shear impact loading
physics.geo-phD. Coker, G. Lykotrafitis, A. Needleman, A. J. Rosakis
Frictional sliding along an interface between two identical isotropic elastic plates under impact shear loading is investigated experimentally and numerically. The plates are held together by a compressive stress and one plate is subject to edge impact near the interface. The experiments exhibit both a crack-like and a pulse-like mode of sliding. Plane stres
Mark J Hadley
The symmetry of Nature under a Space Inversion is described by a Parity operator. Contrary to popular belief, the Parity operator is not unique. The choice of the Parity operator requires several arbitrary decisions to be made. It is shown that alternative, equally plausible, choices leads to the definition of a Parity operator that is conserved by the Weak
H. J. Haubold, W. Wamsteker
The UN/ESA Workshops on Basic Space Science is a long-term effort for the development of astronomy and regional and international co-operation in this field on a world wide basis, particularly in developing nations. The first four workshops in this series (India 1991, Costa Rica and Colombia 1992, Nigeria 1993, and Egypt 1994) addressed the status of astrono
W. Wamsteker, H. J. Haubold
The World Space Observatory/Ultraviolet (WSO/UV) represents a new mission implementation model for large space missions for astrophysics. The process has been brought up to enable, fully scientific needs driven, a logic to be applied to the demands for large collection powers required to undertake space missions which are complementary to the continuously in
L. I. Ognev
By direct numerical simulations of the kinoform refractive lens within the quazioptical approach the effects of shape misalinement were investigated. The quazioptical approach was based on numerical integration of parabolic equation for complex wave amplitude by spep-by-step method with "splitting" procedure. The effect of 2pi- shift compensation was
C. J. Martoff, R. Ayad, M. Katz-Hyman, G. Bonvicini
Drift velocity and longitudinal diffusion measurements are reported for a Negative Ion TPC (NITPC) operating with Helium + carbon disulfide gas mixtures at total pressures from 160 to 700 torr. Longitudinal diffusion at the thermal-limit was observed for drift fields up to at least 700 V/cm in all gas mixtures tested. The results are of particular interest i
Relativistic hodograph equation for a two-dimensional stationary isentropic hydrodynamical motion
physics.flu-dynI. Khalatnikov, A. Kamenshchik
We derive a relativistic hodograph equation for a two-dimensional stationary isentropic hydrodynamical motion. For the case of stiff matter, when the velocity of sound coincides with the light speed, the singularity in this equation disappears and the solutions become regular in all hodograph plane.
Boltzmann-Gibbs Entropy Versus Tsallis Entropy: Recent Contributions to Resolving the Argument of Einstein Concerning "Neither Herr Boltzmann nor Herr Planck has given a definition of W"?
physics.class-phH. J. Haubold, A. M. Mathai, R. K. Saxena
Classical statistical mechanics of macroscopic systems in equilibrium is based on Boltzmann's principle. Tsallis has proposed a generalization of Boltzmann-Gibbs statistics. Its relation to dynamics and nonextensivity of statistical systems are matters of intense investigation and debate. This essay review has been prepared at the occasion of awarding th
The Clausius inequality: implications for nonequilibrium thermodynamic steady states with NEMD corroboration
physics.chem-phChristopher Gunaseelan Jesudason
The Clausius inequality for closed systems was deduced from the Riemann integration of closed Carnot cycle loops for irreversible transitions. The corresponding inequalities for the recently developed open system Carnot cycles are derived here and their properties indicate that no new nonequilibrium entropy results from them as has been proposed over the dec
Hatice Altug, Jelena Vuckovic
We present the design and fabrication of photonic crystal structures exhibiting electromagnetic bands that are flattened in all crystal directions, i.e., whose frequency variation with wavevector is minimized. Such bands can be used to reduce group velocity of light propagating in arbitrary crystal direction, which is of importance for construction of miniat
Experimental demonstration of the slow group velocity of light in two-dimensional coupled photonic crystal microcavity arrays
physics.opticsHatice Altug, Jelena Vuckovic
We recently proposed two-dimensional coupled photonic crystal microcavity arrays as a route to achieve a slow-group velocity of light (flat band) in all crystal directions. In this paper we present the first experimental demonstration of such structures with a measured group velocity below 0.008c and discuss the feasibility of applications such as low-thresh
Matthew Borselli, Kartik Srinivasan, Paul E. Barclay, Oskar Painter
High refractive index contrast optical microdisk resonators fabricated from silicon-on-insulator wafers are studied using an external silica fiber taper waveguide as a wafer-scale optical probe. Measurements performed in the 1500 nm wavelength band show that these silicon microdisks can support whispering-gallery modes with quality factors as high as 5.2 x 1
Trapping and Steering on Lattice Strings: Virtual Slow Waves, Directional and Non-propagating Excitations
physics.class-phGeorg Essl
Using a lattice string model, a number of peculiar excitation situations related to non-propagating excitations and non-radiating sources are demonstrated. External fields can be used to trap excitations locally but also lead to the ability to steer such excitations dynamically as long as the steering is slower than the field's wave propagation. I presen
D. Sarchi, P. F. Bortignon, G. Colo`
A nuclear structure model based on linear response theory (i.e., Random Phase Approximation) and which includes pairing correlations and anharmonicities (coupling with collective vibrations), has been implemented in such a way that it can be applied on the same footing to magic as well as open-shell nuclei. As applications, we have chosen to study the dipole
Axially Deformed Solution of the Skyrme-Hartree-Fock-Bogolyubov Equations using The Transformed Harmonic Oscillator Basis. The program HFBTHO (v1.66p)
nucl-thM. V. Stoitsov, J. Dobaczewski, W. Nazarewicz, P. Ring
We describe the program HFBTHO for axially deformed configurational Hartree-Fock-Bogoliubov calculations with Skyrme-forces and zero-range pairing interaction using Harmonic-Oscillator and/or Transformed Harmonic-Oscillator states. The particle-number symmetry is approximately restored using the Lipkin-Nogami prescription, followed by an exact particle numbe
T. Kawabata, H. Akimune, H. Fujimura, H. Fujita
The $^{11}$B($^3$He$, t$), $^{11}$B($d, d'$), and $^{11}$B($p, p'$) reactions were measured at forward scattering angles including $0^\circ$ to study the isovector and isoscalar spin-flip M1 strengths in $^{11}$B. The measured $^{11}$B($^3$He$, t$) cross sections were compared with the results of the distorted-wave impulse-approximation (DWIA) calcul
Burt Holzman
Two-particle correlations of identical charged pion pairs from Au+Au collisions at sqrt(s_NN) = 200 GeV were measured by the PHOBOS experiment at RHIC. Data for the most central (0--15%) events were analyzed with Bertsch-Pratt (BP) and Yano-Koonin-Podgoretskii (YKP) parameterizations using pairs with rapidities of 0.4 < y < 1.3 and transverse momenta 0.1 < k
David J. Hofman
Results on charged particle production in p+p, d+Au and Au+Au collisions at RHIC energies (sqrt(s_NN) = 19.6 to 200 GeV) are presented. The data exhibit remarkable, and simple, scaling behaviors, the most prominent of which are discussed.
James P. Crutchfield, Olof Gornerup
To analyze the evolutionary emergence of structural complexity in physical processes we introduce a general, but tractable, model of objects that interact to produce new objects. Since the objects--\emph{$epsilon$-machines}--have well defined structural properties, we demonstrate that complexity in the resulting population dynamical system emerges on several
Hokky Situngkir, Yohanes Surya
We construct a majority cellular automata based model to explain the power-law signatures in Indonesian general election results. The understanding of second-order phase transitions between two different conditions inspires the model. The democracy is assumed as critical point between the two extreme socio-political situations of totalitarian and anarchistic
Edson D. Leonel, P. V. E. McClintock, J. Kamphorst Leal da Silva
The chaotic low energy region of the Fermi-Ulam simplified accelerator model is characterised by use of scaling analysis. It is shown that the average velocity and the roughness (variance of the average velocity) obey scaling functions with the same characteristic exponents. The formalism is widely applicable, including to billiards and to other chaotic syst
G. Gonzalez
An equation is obtained to find the Lagrangian for a one-dimensional autonomous system. The continuity of the first derivative of its constant of motion is assumed. This equation is solved for a generic nonconservative autonomous system that has certain quasi-relativistic properties. A new method based on a Taylor series expansion is used to obtain the assoc
Paolo Maria Mariano
We adapt to mixtures the procedure of invariance of external power under the action of SO(3) to deduce balance equations. The two classical axioms about the growths of momentum and moment of momentum are derived with the help of a rule on the structure of the total power. We discuss also the covariance of the balance equations of each constituent and the nat
Olle Haggstrom, Gil Kalai, Elchanan Mossel
Consider an election between two candidates in which the voters' choices are random and independent and the probability of a voter choosing the first candidate is $p>1/2$. Condorcet's Jury Theorem which he derived from the weak law of large numbers asserts that if the number of voters tends to infinity then the probability that the first candidate wi
Wesley Calvert
Theories of classification distinguish classes with some good structure theorem from those for which none is possible. Some classes (dense linear orders, for instance) are non-classifiable in general, but are classifiable when we consider only countable members. This paper explores such a notion for classes of computable structures by working out a sequence
Elchanan Mossel, Ryan O'Donnell
We study a problem related to coin flipping, coding theory, and noise sensitivity. Consider a source of truly random bits $x \in \bits^n$, and $k$ parties, who have noisy versions of the source bits $y^i \in \bits^n$, where for all $i$ and $j$, it holds that $\Pr[y^i_j = x_j] = 1 - \eps$, independently for all $i$ and $j$. That is, each party sees each bit c
Tornike Kadeishvili
We show that the cobar construction of a DG-bialgebra is a homotopy G-algebra. This implies that the bar construction of this cobar is a DG-bialgebra as well.
Suresh Nayak
We give an abstract criterion for pasting pseudofunctors on two subcategories of a category into a pseudofunctor on the whole category. As an application we extend the variance theory of the twisted inverse image $(-)^!$ over schemes to that over formal schemes. Thus we show that over composites of compactifiable maps of noetherian formal schemes, there is a
V. H. Jorge Perez
In this paper we give a formula for counting the number of isolated stable singularities of a stable perturbation of corank 1 germs $f:\C^n,0\to \C^p,0$ with $n<p$ that appear in the image $f(\C^n).$ We also define a set of ${\cal A}$-invariants and show that their finiteness is a necessary and sufficient condition for the ${\cal A}$-finiteness of the germ $
A. Pajitnov
We continue the study of the twisted Novikov homology, introduced in our joint paper with H.Goda (arXiv:math.DG/0312374), and its generalizations. The main applications of the developed algebraic techniques are to the topology of 3-manifolds. We show in particular that the twisted Novikov homology of a 3-manifold M of zero Euler characteristic vanishes if an
Ph. Ellia, D. Franco
We prove an effective bound for the degree of a smooth divisor of a hypersurface of P^n, n>4 (projective space over an algebraically closed field of characteristic zero). Our result follows from a strong (since the degree of the divisor is not involved) generalization of the "Speciality theorem" of Gruson-Peskine, which we prove to hold for any smoot
Ciro Ciliberto, Francesco Russo
In this paper we prove, using a refinement of Terracini's Lemma, a sharp lower bound for the degree of (higher) secant varieties to a given projective variety, which extends the well known lower bound for the degree of a variety in terms of its dimension and codimension in projective space. Moreover we study varieties for which the bound is attained prov
Ivan V. Arzhantsev, Natalia A. Tennova
Affinely closed homogeneous spaces G/H, i.e., affine homogeneous spaces that admit only the trivial affine embedding, are characterized for any affine algebraic group G. As a corollary, a description of affine G-algebras with finitely generated invariant subalgebras is obtained.
Andrei Moroianu, Paul-Andi Nagy, Uwe Semmelmann
We study 6-dimensional nearly Kahler manifolds admitting a Killing vector field of unit length. In the compact case it is shown that up to a finite cover there is only one geometry possible, that of the 3--symmetric space $S^3 \times S^3$.
Christopher Allday
Lin and Sjamaar have used symplectic Hodge theory to obtain canonical equivariant extensions for Hamiltonian actions on closed symplectic manifolds that have the strong Lefschetz property. Here we obtain canonical equivariant extensions much more generally by means of classical Hodge theory.
Tamas Hausel
This is a survey of results and conjectures on mirror symmetry phenomena in the non-Abelian Hodge theory of a curve. We start with the conjecture of Hausel-Thaddeus which claims that certain Hodge numbers of moduli spaces of flat SL(n,C) and PGL(n,C)-connections on a smooth projective algebraic curve agree. We then change our point of view in the non-Abelian
Peter L. Polyakov
We study a boundary value problem in subsonic aeroelasticity.
Winfried Bruns, Joseph Gubeladze
This is an overview of results from our experiment of merging two seemingly unrelated disciplines - higher algebraic K-theory of rings and the theory of lattice polytopes. The usual K-theory is the ``theory of a unit simplex''. A conjecture is proposed on the structure of higher polyhedral K-groups for certain class of polytopes for which the coincid
Wilberd van der Kallen
Let G be a connected reductive linear algebraic group over a field k of characteristic p>0. Let p be large enough with respect to the root system. We show that if a finitely generated commutative k-algebra A with G-action has good filtration, then any noetherian A-module with compatible G-action has finite good filtration dimension.
Yong-Geun Oh
In this paper, we develop a mini-max theory of the action functional over the semi-infinite cycles via the chain level Floer homology theory and construct spectral invariants of Hamiltonian diffeomorphisms on arbitrary, especially on {\it non-exact and non-rational}, compact symplectic manifold $(M,ω)$. To each given time dependent Hamiltonian function $H$ a
Hal Schenck
We study the Hilbert series of a family of ideals J_ϕgenerated by powers of linear forms in k[x_1,...,x_n]. Using the results of Emsalem-Iarrobino, we formulate this as a question about fatpoints in P^{n-1}. In the three variable case this is equivalent to studying the dimension of a linear system on a blow up of P^2. The ideals that arise have the points in
Wesley Calvert
Theories of classification distinguish classes with some good structure theorem from those for which none is possible. Some classes (dense linear orders, for instance) are non-classifiable in general, but are classifiable when we consider only countable members. This paper explores such a notion for classes of computable structures by working out several exa
Wilberd van der Kallen
Let the reductive group G act on the finitely generated commutative k-algebra A. We ask if the finite generation property of the ring of invariants A^G extends to the full rational cohomology ring H^*(G,A). We confirm this when G=SL_2 and also when the characteristic of k is large and the action on A is replaced by the `contracted' action on the Grosshan
Alexander I. Nesterov, Lev V. Sabinin
In (Phys. Rev. D 62, 081501, 2000) we proposed a unified approach to description of continuous and discrete spacetime based on nonassociative geometry and described nonassociative smooth and discrete de Sitter models. In our paper we give the description of nonassociative Friedmann-Robertson-Walker spacetime.
Bobby S Acharya
The space of four dimensional string and $M$ theory vacua with non-Abelian gauge symmetry, chiral fermions and unbroken supersymmetry beyond the electroweak scale appears to be a disconnected space whose different components represent distinct universality classes of vacua. Calculating statistical distributions of physical observables a la Douglas therefore
M R Setare
In this paper we study the Casimir effect for conformally coupled massless scalar fields on background of Static dS$_{4+1}$ spacetime. We will consider the general plane--symmetric solutions of the gravitational field equations and boundary conditions of the Dirichlet type on the branes. Then we calculate the vacuum energy-momentum tensor in a configuration
M. J. Duff
In the first lecture we review the current status of local supersymmetry. In the second lecture we focus on D=11 supergravity as the low-energy limit of M-theory and pose the questions: (1) What are the D=11 symmetries? (2) How many supersymmetries can M-theory vacua preserve?
Hilmar Forkel
Topological charge screening in the QCD vacuum is found to provide crucial nonperturbative contributions to the short-distance expansion of the pseudoscalar (0^{-+}) glueball correlator. The screening contributions enter the Wilson coefficients and are an indispensable complement to the direct instanton contributions. They restore consistency with the anomal
V. I. Shevchenko, Yu. A. Simonov
We analyse the structure of current-current correlators in coordinate space in large $N_c$ limit when the corresponding spectral density takes the form of an infinite sum over hadron poles. The latter are computed in the QCD string model with quarks at the ends, including the lowest states, for all channels. The corresponding correlators demonstrate reasonab
Patrick Janot
The present knowledge of the dark matter discovery and measurement potential of the LHC is reviewed, in the framework of Supersymmetry with R-parity conservation.
Jusak Tandean
The sum of the CP-violating asymmetries A_Omega and A_Lambda in the decay sequence Omega->Lambda K, Lambda->p pi is presently being measured by the E871 experiment. We evaluate contributions to A_Omega from the standard model and from possible new physics, and find them to be smaller than the corresponding contributions to A_Lambda, although not negligibly s
Jochen Bartels, Michael Lublinsky
We summarize the results on the high energy behavior of quark-antiquark exchange in $γ^* γ^*$ elastic scattering. The ladder diagrams, summed in the double logarithmic approximation, provide a perturbative QCD model for secondary reggeon exchange.
M. Conte, M. Palazzi, M. Pusterla, R. Turolla
We show, either quantum mechanically or classically, that the variation of the effective mass induced in a charged particle by the presence of an ultra-strong electromagnetic field may lead to observable consequences. In particular, we discuss how this effect may operate on electrons close to the surface of a magnetar, a neutron star with a super-strong magn
Guido ALTARELLI
We present a concise review of the status of the Standard Model and of the models of new physics.
K. Odagiri
We first suppose that low-energy hadron pair photoproduction reactions gamma(*) gamma(*) -> h h-bar are dominated by s-channel resonance contributions. Their normalization is then calculated by their correspondence with the Reggeon term in the Regge parametrization of the gamma h total cross sections. For the case of p p-bar, we make use of the measured gamm
F. Dalnoki-Veress
Recently there has been a lot of interest around the world in the use of nuclear reactors to measure theta 13, the last undetermined angle in the 3-neutrino mixing scenario. In this paper the motivations for theta 13 measurement using short baseline nuclear reactor experiments are discussed. The features of such an experiment are described in the context of
Ronan McNulty
The inclusive di-photon cross-section is measured in the central region and found to be in good agreement with NLO QCD predictions. Cross-sections are presented for events containing an energetic photon in addition to a heavy flavour jet. The ratio of photon+c to photon+b events is also measured. Results are currently statistically limited and in agreement w
Proton - Lambda correlations in Au-Au Collisions at $\sqrt{s_{NN}} = 200$ GeV from the STAR experiment
hep-exG. Renault, the STAR Collaboration
The space-time evolution of the source of particles formed in the collision of nuclei can be studied through particle correlations. The STAR experiment is dedicated to study ultra-relativistic heavy ions collisions and allows to measure non-identical strange particle correlations. The source size can be extracted by studying $p-Λ$, $\bar{p}-\barΛ$, $\bar{p}-