June 2002 arXiv papers
Showing 1–100 of 2,703 papers
John F. Gunion, Howard E. Haber
A CP-even neutral Higgs boson with Standard-Model-like couplings may be the lightest scalar of a two-Higgs-doublet model. We study the decoupling limit of the most general CP-conserving two-Higgs-doublet model, where the mass of the lightest Higgs scalar is significantly smaller than the masses of the other Higgs bosons of the model. In this case, the proper
Z. Burda, A. Krzywicki
We define a statistical ensemble of non-degenerate graphs, i.e. graphs without multiple- and self-connections between nodes. The node degree distribution is arbitrary, but the nodes are assumed to be uncorrelated. This completes our earlier publication \cite{bck}, where trees and degenerate graphs were considered. An efficient algorithm generating non-degene
P. G. Silvestrov, J. Tworzydlo, C. W. J. Beenakker
We re-examine the problem of the "Loschmidt echo", which measures the sensitivity to perturbation of quantum chaotic dynamics. The overlap squared $M(t)$ of two wave packets evolving under slightly different Hamiltonians is shown to have the double-exponential initial decay $\propto \exp(-{\rm constant}\times e^{2λ_0 t})$ in the main part of phase sp
Sanghyun Park, Klaus Schulten
Finding representative reaction pathways is necessary for understanding mechanisms of molecular processes, but is considered to be extremely challenging. We propose a new method to construct reaction paths based on mean first-passage times. This approach incorporates information of all possible reaction events as well as the effect of temperature. The method
Mei Huang, Pengfei Zhuang, Weiqin Chao
The effect of electric and color neutrality on 2-flavor color superconductivity has been investigated. It has been found that the effect of the charge neutrality on a 2-flavor quark system is very different from that on a 3-flavor system. The BCS diquark pair in 2-flavor color superconducting phase has been largely reduced by the large Fermi momentum of elec
Brian P. Dolan, C. Nash
The Atiyah-Singer index theorem is investigated on various compact manifolds which admit finite matrix approximations (``fuzzy spaces'') with a view to applications in a modified Kaluza-Klein type approach in which the internal space consists of a finite number of points. Motivated by the chiral nature of the standard model spectrum we investigate ma
Akira Furukawa
Recently, a systematic experiment measuring critical anomaly of viscosity of polymer solutions has been reported by H. Tanaka and his co-workers (Phys.Rev.E, 65, 021802, (2002)). According to their experiments, the dynamic critical exponent of viscosity y_c drastically decreases with increasing the molecular weight. In this article the kinetic coefficients r
Mladen Pavicic
We consider algebras underlying Hilbert spaces used by quantum information algorithms. We show how one can arrive at equations on such algebras which define n-dimensional Hilbert space subspaces which in turn can simulate quantum systems on a quantum system. In doing so we use MMP diagrams and linear algorithms. MMP diagrams are tractable since an n-block of
Vladimir Baranovsky
It known from the work of Feigin-Tsygan, Weibel and Keller that the cohomology groups of a smooth complex variety X can be recovered from (roughly speaking) its derived category of coherent sheaves. In this paper we show that for a finite group G acting on X the same procedure applied to G-equivariant sheaves gives the orbifold cohomology of X/G. As an appli
Keith R. Dienes, Arash Mafi
When closed strings propagate in extra compactified dimensions, a rich spectrum of Kaluza-Klein states and winding states emerges. Since the masses of Kaluza-Klein states and winding states play a reciprocal role, it is often believed that either the lightest Kaluza-Klein states or the lightest winding states must be at or below the string scale. In this pap
A. Garmash
The results on charmless B meson decays to three-body Khh final states, where h stands for the charged or neutral pion or kaon are presented. The data sample used in this analysis consists of 43 1/fb on-resonance data collected with the Belle detector operating at the KEKB collider.
J. P. Park, P. Eames, D. M. Engebretson, J. Berezovsky
We have observed localized spin-wave modes in individual thin-film ferromagnetic wires using time-resolved Kerr microscopy as a micron-scale spectroscopic probe. The localization is due to the partial demagnetization of a wire when an external field is applied in the plane of the film and perpendicular to the long axis of the wire. Spatially-resolved spectra
Uri Peskin, Michael Galperin, Abraham Nitzan
The tunneling time of particle through given barrier is commonly defined in terms of "internal clocks" which effectively measure the interaction time with internal degrees of freedom of the barrier. It is known that this definition of the time scale for tunneling is not unique in the sense that it depends on the clock used to define it. For the case
Sun Zhang, Fan Wang
We study the interference effects between three weakly linked trapped Bose-Einstein condensates (BEC) as a generalization of the two-component condensates. Three coupled Gross-Pitaevskii equations (GPE) are used to describe the dynamics of the system. The nonsinusoidal oscillation is found as a generalization of the Josephson effect in superconductivity. The
Sun Zhang
The effects of pressure on heavy-fermion alloys are studied in the framework of Yoshimori-Kasai model under the coherent potential approximation. A unified picture is presented for both the electron-type heavy-fermion systems and the hole-type heavy-fermion systems. The density of states of $f$ electrons is calculated over the whole range of the doping conce
Michael Galperin, Abraham Nitzan, Ilan Benjamin
This paper presents results of numerical simulations of electron tunneling through water that extend our previous calculations on such systems in several ways. First, a tip-substrate configuration is used; second, calculations are carried in the presence of an external potential bias; third, the image potential that reflects the interaction of the electron w
Dvira Segal, Abraham Nitzan
A framework for estimating heating and expected temperature rise in current carrying molecular junctions is described. Our approach is based on applying the Redfield approximation to a tight binding model for the molecular bridge supplemented by coupling to a phonon bath. This model, used previously to study thermal relaxation effects on electron transfer an
Hyun C. Lee
The density of states of one-dimensional disordered electron systems with long range Coulomb interaction is studied in the weak pinning limit. The density of states is found to follow a power law with an exponent determined by localization length, and this power law behavior is consistent with the existing numerical results.
Systematic trends in the electronic structure parameters of 4d transition metal oxides SrMO_{3} (M = Zr, Mo, Ru, and Rh)
cond-mat.str-elY. S. Lee, J. S. Lee, T. W. Noh, Douck-Young Byun
We investigated the electronic structures of the perovskite-type 4$d$ transition metal oxides Sr$M$O$_3$ ($M$ = Zr, Mo, Ru, and Rh) using their optical conductivity spectra $σ(ω)$. The interband transitions in $σ(ω)$ are assigned, and some important physical parameters, such as on-site Coulomb repulsion energy $U$, charge transfer energy $Δ_{pd}$, and crysta
Self-Gravitating Magnetically-Supported Protostellar Disks and the Formation of Substellar Companions
astro-phZhi-Yun Li
Isolated low-mass stars are formed, in the standard picture, from the collapse of dense cores condensed out of strongly magnetized molecular clouds. The dynamically collapsing inflow traps nearly half of the critical magnetic flux needed for the core support and deposits it in a small region surrounding the protostar. It has been argued previously that the d
S. G. Rubin
The mechanism of production of a large number of universes is considered. It is shown that universes with parameters suitable for creation of life are necessarily produced as a result of quantum fluctuations. Fractal structures are formed provided fluctuations take place near a maximum of the potential. Several ways of formation of similar fractal structures
Yasushi Fukazawa, Naomi Kawano, Akimitsu Ohto
We observed a group of galaxies, HCG 57, with ASCA. Regardless that their member galaxies are dominated by spiral galaxies, we detected extended thermal X-ray emission that is attributed to hot gas with a temperature of $1.04\pm0.10$ keV. This is the second clear detection of thermal X-ray emission from a spiral-dominant group of galaxies after HCG 92. The l
U. W. Heinz, A. Hummel, M. A. Lisa, U. A. Wiedemann
We discuss symmetry constraints on the azimuthal oscillations of two-particle correlation (Hanbury Brown--Twiss interferometry) radii for non-central collisions between equal spherical nuclei. We also propose a new method for correcting in a model-independent way the emission angle dependent correlation function for finite event plane resolution and angular
Alessandra Agostini, Giovanni Amelino-Camelia, Michele Arzano
We construct a Dirac equation that is consistent with one of the recently-proposed schemes for a "doubly-special relativity", a relativity with both an observer-independent velocity scale (still naturally identified with the speed-of-light constant) and an observer-independent length/momentum scale (possibly given by the Planck length/momentum). We find that
J. Greenhough, S. C. Chapman, S. Chaty, R. O. Dendy
Measurement of the energy emitted from accreting astrophysical systems provides an observational constraint on the plasma processes that may be operating within the disk. Here we examine the continual time variation over the past six years of the total X-ray flux from the microquasar GRS 1915+105. The application of differencing and rescaling techniques to R
Scaling Behavior of $(N_{ch})^{-1}dN_{ch}/dη$ at $\sqrt{s_{NN}} = 130$ GeV by the PHOBOS Collaboration and Its Implication --A Possible Explanation Employing the Ornstein-Uhlenbeck Process--
nucl-thM. Biyajima, M. Ide, T. Mizoguchi, N. Suzuki
Recently, interesting data concerning $dN_{ch}/dη$ in Au-Au collisions [$η=-\ln \tan (θ/2)$] with centrality cuts have been reported from the PHOBOS Collaboration. In most treatment these data are divided by the number of participants (nucleons) in collisions. Instead of this method, we use the total multiplicity $N_{ch} = \int (dN_{ch}/dη)dη$ and find that
I. S. Beloborodov, A. V. Andreev, A. I. Larkin
We study Coulomb blockade (CB) oscillations in the thermodynamics of a metallic grain which is connected to a lead by a tunneling contact with a large conductance $g_0$ in a wide temperature range, $E_Cg_0^4 e^{-g_0/2}<T<E_C$, where $E_C$ is the charging energy. Using the instanton analysis and the renormalization group we obtain the temperature dependence o
S. Recksiegel, Y. Sumino
Recently it has been shown that the gross structure of the bottomonium spectrum is reproduced reasonably well within the non-relativistic boundstate theory based on perturbative QCD. In that calculation, however, the fine splittings and the S-P level splittings are predicted to be considerably narrower than the corresponding experimental values. We investiga
J. Ponce de Leon
In brane-world theory in five dimensions, the bulk metric is usually written in gaussian coordinates, where $g_{4μ} = 0$ and $g_{44} = - 1$. However, the choice $g_{44} = - 1$ is an external condition, not a requirement of the field equations. In this paper we study the consequences of having $g_{44} = εΦ^2$, where $ε= \pm 1$ and $Φ$ is a scalar function var
Charalampos Anastasiou, Kirill Melnikov
We compute the total cross-section for direct Higgs boson production in hadron collisions at NNLO in perturbative QCD. A new technique which allows us to perform an algorithmic evaluation of inclusive phase-space integrals is introduced, based on the Cutkosky rules, integration by parts and the differential equation method for computing master integrals. Fin
Kazuyuki Fujii
We construct the exchange gate with small elementary gates on the space of qudits, which consist of three controlled shift gates and three "reverse" gates. This is a natural extension of the qubit case. We also consider a similar subject on the Fock space, but in this case we meet with some different situation. However we can construct the exchange g
Kazutoshi Ohta, Takashi Yokono
We found a gravity solution of p+1 dimensional extended object with SO(p)xSO(9-p) symmetry which has zero pressure and zero dilaton charge. We expect that this object is a residual tachyon dust after tachyon condensation of brane and anti-brane system discussed by Sen, recently. We also discuss the Hawking temperature and some properties of this object.
Education Curricula of the Regional Centres for Space Science and Technology Education (Affiliated to the United Nations)
physics.ed-phH. J. Haubold
Since 1988, the United Nations, through the Programme on Space Applications, is supporting the establishment and operation of regional Centres for Space Science and Technology Education in Africa, Asia and the Pacific, Latin America and the Caribbean, and Western Asia. Simultaneously, education curricula have been developed for remote sensing and geographic
A Gaussian-optical Approach to Stable Periodic Orbit Resonances of Partially Chaotic Dielectric Micro-cavities
physics.opticsH. E. Tureci, H. G. L. Schwefel, E. E. Narimanov, A. Douglas Stone
The quasi-bound modes localized on stable periodic ray orbits of dielectric micro-cavities are constructed in the short-wavelength limit using the parabolic equation method. These modes are shown to coexist with irregularly spaced "chaotic" modes for the generic case. The wavevector quantization rule for the quasi-bound modes is derived and given a s
C. Ciofi degli Atti, B. Z. Kopeliovich
The final state interaction in DIS of leptons off a nucleus A, due to the propagation of the struck nucleon debris and its hadronization in the nuclear environment is considered. The effective cross section of such a partonic system with the nucleons of the medium and its time dependence are estimated on the basis of a model which takes into account the prod
Artyom Yurov
The discrete symmetry's dressing chains of the nonlinear Schrodinger equation (NLS) and Davey-Stewartson equations (DS) are consider. The modified NLS (mNLS) equation and the modified DS (mDS) equations are obtained. The explicitly reversible Backlund auto-transformations for the mNLS and mDS equations are constructed. We demonstrate discrete symmetry
G. Gaeta, P. Morando
We extend Michel's theorem on the geometry of symmetry breaking [L. Michel, {\it Comptes Rendus Acad. Sci. Paris} {\bf 272-A} (1971), 433-436] to the case of pure gauge theories, i.e. of gauge-invariant functionals defined on the space ${\cal C}$ of connections of a principal fiber bundle. Our proof follows closely the original one by Michel, using sever
Dan Abramovich
A cheap method for constructing canonical models and complete moduli for complex projective varieties with a structure called "rational plurifibration" is given. A result about semistable reduction (whose nature is slightly different from alg-geom/9707012) is deduced. The method involves recursive application of moduli stacks of twisted stable maps (
Gianni Dal Maso, Rodica Toader
We study a variant of the variational model for the quasi-static growth of brittle fractures proposed by Francfort and Marigo. The main feature of our model is that, in the discrete-time formulation, in each step we do not consider absolute minimizers of the energy, but, in a sense, we look for local minimizers which are sufficiently close to the approximate
Kamal Khuri-Makdisi
We use an embedding of the symmetric $d$th power of any algebraic curve $C$ of genus $g$ into a Grassmannian space to give algorithms for working with divisors on $C$, using only linear algebra in vector spaces of dimension $O(g)$, and matrices of size $O(g^2)\times O(g)$. When the base field $k$ is finite, or if $C$ has a rational point over $k$, these give
Gravity In A Model Of Multi Branes Alternated Between Minkowski And AdS Spacetime In The Fifth Dimension
hep-thYun-Song Piao, Xinmin Zhang, Yuan-Zhong Zhang
We construct in this paper a multi-brne model with Minkowski and AdS spacetime alternated in the fifth dimension and study the gravity on the brane of our universe. We will show that in this model there are both the graviton-like resonant states which generates the "quasi-localized gravity" and the resonant states of the massive KK mode. This model g
D. London, N. Sinha, R. Sinha
Direct CP violation in B -> J/Psi K is a clean test for new physics. However, the direct CP asymmetry will vanish if the new-physics amplitude has the same strong phase as the standard-model amplitude. We show that this type of new physics can still be detected via an angular analysis of the sister decay mode B -> J/Psi K^*. Time-dependent measurements and t
Yun-Song Piao, Rong-Gen Cai, Xinmin Zhang
We study the Randall-Sundrum model with a small 4D effective cosmological constant on the brane, and drive a corrected radion potential following the Goldberger-Wise mechanism. We then discuss the effect of the 4D effective cosmological constant on the stability of the brane-system, and find that to quintessence determined by updated observation, the proper
S. Nagataki
We have estimated the number flux of of mu-neutrinos which are produced due to the hadronic interactions between the cosmic rays coming from a neutron star and the matter in a companion star. The event rate at 1 km^2 detectors of high-energy neutrinos such as ICECUBE, ANTARES and NESTOR is also estimated to be 2.7 \times 10^4 events yr^-1 when the source is
Hugh E. Montgomery
A substantial body of data is described by the Standard Model of particle physics. However the description is far from perfect and there is a growing number of internal inconsistencies. These fall short of qualifying as discoveries; nevertheless, examination of their merits is both interesting and worthwhile. The existence of three families of quarks and lep
J. Detwiler, G. Gratta, N. Tolich, Y. Uchida
We study the effect of naval nuclear reactors on the study of neutrino oscillations. We find that the presence of naval reactors at unknown locations and times may limit the accuracy of future very long baseline reactor-based neutrino oscillation experiments. At the same time we argue that a nuclear powered surface ship such as a large Russian ice-breaker ma
Yvonne Choquet-Bruhat, James W. York
We write a first order symmetric hyperbolic system coupling the Riemann with the dynamical acceleration of a relativistic fluid. W determine the associated, coupled, Bel - Robinson energy, and the integral equality that it satisfies.
On the stability of the critical state in composite superconductors with an inhomogeneous temperature profile
cond-mat.supr-conNizam A. Taylanov
The problem of the thermal and magnetic destruction of the critical state in composite superconductors is investigated. The initial distributions of temperature and electromagnetic field are assumed to be essentially inhomogeneous. The limit of the thermomagnetic instability in quasi-stationary approximation is determined. The obtained integral criterion, un
Dynamical Decimation Renormalization-Group Technique: Kinetic Gaussian Model on Non-Branching, Braching and Multi-branching Koch Curve
cond-mat.dis-nnJian-Yang Zhu, Z. R. Yang
A generalizing formulation of dynamical real-space renormalization that suits for arbitrary spin systems is suggested. The new version replaces the single-spin flipping Glauber dynamics with the single-spin transition dynamics. As an application, in this paper we mainly investigate the critical slowing down of the Gaussian spin model on three fractal lattice
Jian-Yang Zhu, Z. R. Yang
In this paper, the single-spin transition dynamics is used to investigate the kinetic Gaussian model in a periodic external field. We first derive the fundamental dynamic equations, and then treat an isotropic d-dimensional hypercubic lattice Gaussian spin system with Fourier's transformation method. We obtain exactly the local magnetization and the equa
Jian-Yang Zhu, Z. R. Yang
In this paper, we have exactly solved Glauber critical dynamics of the Gaussian model on three dimensions. Of course, it is much easy to apply to low dimensional case. The key steps are that we generalize the spin change mechanism from Glauber's single-spin flipping to single-spin transition and give a normalized version of the transition probability . W
M. B. Hastings, I. Martin, D. Mozyrsky
We consider a quantum point contact between two Luttinger liquids coupled to a mechanical system (oscillator). For non-vanishing bias, we find an effective oscillator temperature that depends on the Luttinger parameter. A generalized fluctuation-dissipation relation connects the decoherence and dissipation of the oscillator to the current-voltage characteris
Electromagnetic Surface Modes at Interfaces with Negative Refractive Index make a "Not-Quite-Perfect" Lens
cond-matF. D. M. Haldane
Interfaces between media with negative relative refractive index generically support propagating electromagnetic surface polariton modes with large wavenumber. The relation of these modes to a recent prediction by Pendry of ``perfect (real) image formation'' by a parallel slab of negative-refractive-index material is analyzed. The ``perfect image'
Near-IR 2D-Spectroscopy of the 4''x 4'' region around the Active Galactic Nucleus of NGC1068 with ISAAC/VLT
astro-phEmmanuel Galliano, Danielle Alloin
We present new near-IR long slit spectroscopic data obtained with ISAAC on VLT/ANTU (ESO/Paranal) of the central 4''x 4'' region surrounding the central engine of NGC1068 . Bracket Gamma (Bg) and H2 emission line maps and line profile grids are produced, at a spatial resolution~0.5" and spectral resolution 35km/s. Two conspicuous knots of
N. Mirabal, J. P. Halpern, S. R. Kulkarni, S. Castro
We present sequential optical spectra of the afterglow of GRB 010222 obtained one day apart using the Low Resolution Imaging Spectrometer (LRIS) and the Echellette Spectrograph and Imager (ESI) on the Keck telescopes. Three low-ionization absorption systems are spectroscopically identified at z1=1.47688, z2=1.15628, and z3=0.92747. The higher resolution ESI
A. Ortiz, S. K. Solanki, V. Domingo, M. Fligge
Sunspots, faculae and the magnetic network contribute to solar irradiance variations. The contribution due to faculae and the network is of basic importance, but suffers from considerable uncertainty. We determine the contrasts of active region faculae and the network, both as a function of heliocentric angle and magnetogram signal. To achieve this, we analy
The Microlensing Event MACHO-99-BLG-22/OGLE-1999-BUL-32: An Intermediate Mass Black Hole, or a Lens in the Bulge
astro-phD. P. Bennett, A. C. Becker, J. J. Calitz, B. R. Johnson
We present an re-analysis of the longest timescale gravitational microlensing event discovered to date: MACHO-99-BLG-22/OGLE-1999-BUL-32, which was discovered by both the MACHO and OGLE microlensing alert systems. Our analysis of this microlensing parallax event includes a likelihood analysis of the lens position based upon a standard model of the Galactic v
Discovery of an ionized Fe-K edge in the z=3.91 Broad Absorption Line Quasar APM 08279+5255 with XMM-Newton
astro-phG. Hasinger, N. Schartel, S. Komossa
Recent XMM-Newton observations of the high-redshift, lensed, broad absorption line (BAL) quasi-stellar object APM 08279+5255, one of the most luminous objects in the universe, allowed the detection of a high column density absorber ($N_H \approx 10^{23}$ cm$^{-2}$) in the form of a K-shell absorption edge of significantly ionized iron (Fe XV - XVIII) and cor
Jun Kataoka, Chiharu Tanihata, Nobuyuki Kawai, Fumio Takahara
We present the results of a long-look monitoring of 3C273 with RXTE between 1996 and 2000. A total of 230 observations amounts to a net exposure of 845ksec, with this spectral and variability analysis of 3C273 covering the longest observation period available at hard X-ray energies. Flux variations by a factor of 4 have been detected over 4years, whereas les
M. J. Duff, James T. Liu, H. Sati
We perform a one-loop test of the holographic interpretation of the Karch-Randall model, whereby a massive graviton appears on an AdS_4 brane in an AdS_5 bulk. Within the AdS/CFT framework, we examine the quantum corrections to the graviton propagator on the brane, and demonstrate that they induce a graviton mass in exact agreement with the Karch-Randall res
Matthias Neubert
It is argued that the dominant subleading shape-function contributions to the endpoint region of the charged-lepton energy spectrum in B -> X_u l nu decays can be related in a model-independent way to an integral over the B -> X_s gamma photon spectrum. The square root of the fraction of B -> X_u l nu events with charged-lepton energy above E_0=2.2 GeV can b
C. C. Homes, J. M. Tranquada, Q. Li, A. R. Moodenbaugh
The optical conductivity of La(2-x)Sr(x)NiO(4) has been interpreted in various ways, but so far the proposed interpretations have neglected the fact that the holes doped into the NiO(2) planes order in diagonal stripes, as established by neutron and X-ray scattering. Here we present a study of optical conductivity in La(2)NiO(4+d) with d=2/15, a material in
Yan Chen, Z. D. Wang, Jian-Xin Zhu, C. S. Ting
Based on an effective model Hamiltonian with competing antiferromagnetic (AF) and d-wave superconductivity (DSC) interactions, the vortex charge in high T_c superconductors is investigated by solving self-consistently the Bogoliubov-de Gennes equations. We found that the vortex charge is always negative when a sufficient strength of AF order is induced insid
L. Borda, G. Zarand, W. Hofstetter, B. I. Halperin
We study a symmetrical double quantum dot (DD) system with strong capacitive inter-dot coupling using renormalization group methods. The dots are attached to separate leads, and there can be a weak tunneling between them. In the regime where there is a single electron on the DD the low-energy behavior is characterized by an SU(4)-symmetric Fermi liquid theor
Matthias Jakob, Janos Bergou
We present a conditional quantum eraser which erases the a priori knowledge or the predictability of the path a photon takes in a Young-type double-slit experiment with two fluorescent four-level atoms. This erasure violates a recently derived erasure relation which must be satisfied for a conventional, unconditional quantum eraser that aims to find an optim
A. Jakobek, K. A. Meissner, M. Olechowski
We consider the higher order gravity with dilaton and with the leading string theory corrections taken into account. The domain wall type solutions are investigated for arbitrary number of space-time dimensions. The explicit formulae for the fixed points and asymptotic behavior of generic solutions are given. We analyze and classify solutions with finite eff
Ghost Condensates and Dynamical Breaking of SL(2,R) in Yang-Mills in the Maximal Abelian Gauge
hep-thV. E. R. Lemes, M. S. Sarandy, S. P. Sorella
Ghost condensates of dimension two in SU(N) Yang-Mills theory quantized in the Maximal Abelian Gauge are discussed. These condensates turn out to be related to the dynamical breaking of the SL(2,R) symmetry present in this gauge
Wlodzimierz Kluzniak, William H. Lee
In 3-d SPH simulations of the coalescence of a quark star with a pseudo-Newtonian black hole all of the quark matter is quickly accreted by the black hole. The Madsen-Caldwell-Friedman argument against the existence of quark stars may need to be re-examined.
M. L. Mangano, M. Moretti, F. Piccinini, R. Pittau
This paper presents a new event generator, ALPGEN, dedicated to the study of multiparton hard processes in hadronic collisions. The code performs, at the leading order in QCD and EW interactions, the calculation of the exact matrix elements for a large set of parton-level processes of interest in the study of the Tevatron and LHC data. The current version of
Robbert Dijkgraaf, Cumrun Vafa
We show that B-model topological strings on local Calabi-Yau threefolds are large N duals of matrix models, which in the planar limit naturally give rise to special geometry. These matrix models directly compute F-terms in an associated N=1 supersymmetric gauge theory, obtained by deforming N=2 theories by a superpotential term that can be directly identifie
A. V. Belitsky, D. Müller
Hard exclusive leptoproductions of real photons, lepton pairs and mesons are the most promising tools to unravel the three-dimensional picture of the nucleon, which cannot be deduced from conventional inclusive processes like deeply inelastic scattering.
K. S. Babu, Christopher Kolda
Recent observations of neutrino oscillations imply non-zero neutrino masses and flavor violation in the lepton sector, most economically explained by the seesaw mechanism. Within the context of supersymmetry, lepton flavor violation (LFV) among the neutrinos can be communicated by renormalization group flow to the sleptons and from there to the charged lepto
Absence of Metal-Insulator-Transition and Coherent Interlayer Transport in oriented graphite in parallel magnetic fields
cond-mat.str-elH. Kempa, H. C. Semmelhack, P. Esquinazi, Y. Kopelevich
Measurements of the magnetoresistivity of graphite with a high degree of control of the angle between the sample and magnetic field indicate that the metal-insulator transition (MIT), shown to be induced by a magnetic field applied perpendicular to the layers, does not appear in parallel field orientation. Furthermore, we show that interlayer transport is co
George M. Hockney, Pieter Kok, Jonathan P. Dowling
The creation of specified quantum states is important for most, if not all, applications in quantum computation and communication. The quality of the state preparation is therefore an essential ingredient in any assessment of a quantum-state gun. We show that the fidelity, under the standard definitions is not sufficient to assess quantum sources, and we pro
Filipe Paccetti Correia, Michael G. Schmidt, Zurab Tavartkiladze
We construct a 5D SUSY SU(6) GUT on an $S^{(1)}/Z_2\tm Z_2'$ orbifold. The first stage of gauge symmetry breaking occurs through compactification and a specific selection of boundary conditions. Additional symmetries play a crucial role for the generation of $μ$ and $Bμ$ terms of appropriate values: with a $SU(2)_{cus}$ custodial symmetry the Higgs doubl
David R. Nelson
We propose coating spherical particles or droplets with anisotropic nano-sized objects to allow micron-scale colloids to link or functionalize with a four-fold valence, similar to the sp3 hybridized chemical bonds associated with, e.g., carbon, silicon and germanium. Candidates for such coatings include triblock copolymers, gemini lipids, metallic or semicon
T. Rauscher, K. H. Guber
Direct neutron capture on 62Ni is calculated in the DWBA and the cross sections in the energy range relevant for s-process nucleosynthesis are given. It is confirmed that the thermal value of the capture cross section contains a subthreshold resonance contribution. Contrary to previous investigations it is found that the capture at higher energies is dominat
J. B. Coe, Y. Mao, M. E. Cates
We present some analytic results for the steady states of the Penna model of sen escence, generalised to allow genetically identical individuals to die at differ ent ages via an arbitrary survival function. Modelling this with a Fermi functio n (of modest width) we obtain a clear mortality plateau late in life: something that has so far eluded explanation wi
Sacha Davidson, Alejandro Ibarra
In supersymmetric models, the CP asymmetry produced in the decay of the lightest right-handed neutrino, $\equiv epsilon$, can be written as a function of weak scale parameters. We introduce a way of separating epsilon into contributions from the various weak-scale phases, and study the contribution of potentially measurable neutrino phases to leptogenesis. W
W. M. Alberico, F. Giacosa, M. Nardi, C. Ratti
We employ the Nambu Jona--Lasinio model to determine the vacuum pressure on the quarks in a baryon and hence their density inside. Then we estimate the baryonic masses by implementing the local density approximation for the mean field quark energies obtained in a uniform and isotropic system. We obtain a fair agreement with the experimental masses.
D. Wilson, J. Lee, M. S. Kim
Some non-classical properties such as squeezing, sub-Poissonian photon statistics or oscillations in photon-number distributions may survive longer in a phase-sensitive environment than in a phase-insensitive environment. We examine if entanglement, which is an inter-mode non-classical feature, can also survive longer in a phase-sensitive environment. Differ
Double logarithms, $ln^2(1/x)$, and the NLO DGLAP evolution for the non-singlet component of the nucleon spin structure function, $g_1$
hep-phBeata Ziaja
Theoretical predictions show that at low values of Bjorken $x$ the spin structure function, $g_1$ is influenced by large logarithmic corrections, $ln^2(1/x)$, which may be predominant in this region. These corrections are also partially contained in the NLO part of the standard DGLAP evolution. Here we calculate the non-singlet component of the nucleon struc
Nobuyuki Sakai, Shinpei Shibata
We reconstruct a 3+1 formalism of general relativistic electromagnetism, and derive the equations of motion of charged particles in the pulsar magnetosphere, taking account of the inclination between the rotation axis and the magnetic axis. Apart from the previous works where space charge is evaluated by assuming the flow velocity being the light speed, we a
Influence of internal disorder on the superconducting state in the organic layered superconductor kappa-(BEDT-TTF)2Cu[N(CN)2]Br
cond-matM. Pinteric, S. Tomic, M. Prester, D. Drobac
We report high-sensitivity AC susceptibility measurements of the penetration depth in the Meissner state of the layered organic superconductor kappa-(BEDT-TTF)2Cu[N(CN)2]Br. We have studied nominally pure single crystals from the two different syntheses and employed controlled cooling procedures in order to minimize intrinsic remnant disorder at low temperat
Serge Florens, Antoine Georges
We introduce a representation of electron operators as a product of a spin-carry ing fermion and of a phase variable dual to the total charge (slave quantum rotor). Based on this representation, a new method is proposed for solving multi-orbital Anderson quantum impurity models at finite interaction strength U. It consists in a set of coupled integral equati
Rituparno Goswami, Pankaj S Joshi
We examine here in what way the pressures affect the final fate of a continual gravitational collapse. It is shown that the presence of a non-vanishing pressure gradient in the collapsing cloud determines directly the epoch of formation of trapped surfaces and the apparent horizon, thus changing the causal structure in the vicinity of singularity.
D. G. Cerdeno, C. Munoz
We analyze some phenomenological implications of heterotic M-theory with five-branes. Recent results for the effective 4-dimensional action are used to perform a systematic analysis of the parameter space, finding the restrictions that result from requiring the volume of the Calabi-Yau to remain positive. Then the different scales of the theory, namely, the
J. F. R. Archilla, Yu B. Gaididei, P. L. Christiansen, J. Cuevas
The existence, stability and movability of breathers in a model for alpha-helix proteins is studied. This model basically consists a chain of dipole moments parallel to it. The existence of localized linear modes brings about that the system has a characteristic frequency, which depends on the curvature of the chain. Hard breathers are stable, while soft one
Kanehisa Takasaki
A chain of one-dimensional Schrödinger operators connected by successive Darboux transformations is called the ``Darboux chain'' or ``dressing chain''. The periodic dressing chain with period $N$ has a control parameter $α$. If $α\not= 0$, the $N$-periodic dressing chain may be thought of as a generalization of the fourth or fifth (depending
Betti Hartmann
We consider axially symmetric SU(2) Yang-Mills-Higgs (YMH) multimonopoles in Brans-Dicke theory for winding number n > 1. In analogy to the spherically symmetric n=1 solutions, we find that the axially symmetric solutions exist for higher values of the gravitational coupling than in the pure Einstein gravity case. For large values of the gravitational coupli
Ivelina Bobtcheva, Maria Grazia Messia
The HKR (Hennings-Kauffman-Radford) framework is used to construct invariants of 4-thickenings of 2-dimensional CW complexes under 2-deformations (1- and 2- handle slides and creations and cancellations of 1-2 handle pairs). The input of the invariant is a finite dimensional unimodular ribbon Hopf algebra A and an element in a quotient of its center, which d
Magnus Jacobsson
In [Duke Math. J. 101 (1999) 359-426], Mikhail Khovanov constructed a homology theory for oriented links, whose graded Euler characteristic is the Jones polynomial. He also explained how every link cobordism between two links induces a homomorphism between their homology groups, and he conjectured the invariance (up to sign) of this homomorphism under ambien
M. Tohyama, A. S. Umar
The strength functions of quadrupole modes in the unstable oxygen isotopes 22O and 24O are calculated using an extended version of the time-dependent Hartree-Fock theory known as the time-dependent density-matrix theory (TDDM). It is found that TDDM gives the lowest quadrupole states which are energetically shifted upward and become significantly collective
P. Ko, Jae-hyeon Park, G. Kramer
We consider the gluino-mediated SUSY contributions to B0 - B0 bar mixing, B -> J/psi K_S and B -> X_d gamma in the mass insertion approximation. We find the LL mixing parameter can be as large as |delta_{13}^d_{LL}| < 2*10^-1, but the LR mixing is strongly constrained by the B -> X_d gamma branching ratio and we find |delta_{13}^d_{LR}| < 10^-2. The implicat
X. Y. Wang, Z. G. Dai, T. Lu
Gamma-ray bursts may occur within pulsar wind bubbles (PWBs) under a number of scenarios, such as the supranova-like models in which the progenitor pulsar drives a powerful wind shocking against the ambient medium before it comes to death and produces a fireball. We here study the early afterglow emission from GRBs expanding into such a PWB environment. Diff
Gavin K. Brennen
Preparing many body entangled states efficiently using available interactions is a challenging task. One solution may be to couple a system collectively with a probe that leaves residual entanglement in the system. We investigate the entanglement produced between two possibly distant qubits 1 and 2 that interact locally with a third qubit 3 under unitary evo
G. Brida, E. Cagliero, G. Falzetta, M. Genovese
De Broglie - Bohm (dBB) theory is a deterministic theory, built for reproducing almost all Quantum Mechanics (QM) predictions, where position plays the role of a hidden variable. It was recently shown that different coincidence patterns are predicted by QM and dBB when a double slit experiment is realised under specific conditions and, therefore, an experime
Robert R. Tucci
Given a uniform ensemble of quantum density matrices $ρ$, it is useful to calculate the mean value over this ensemble of a product of entries of $ρ$. We show how to calculate such moments in this paper. The answer involves well known results from Group Representation Theory and Random Matrix Theory. This quantum problem has a well known classical counterpart
Karl-Erik Eriksson
A small quantum scattering system (the microsystem) is studied in interaction with a large quantum system (the macrosystem) described by unknown stochastic variables. The interaction between the two systems is diagonal for the microsystem in a certain basis, and it leads to an imprint on the macrosystem. Moreover, the interaction is assumed to involve only s
Tractability of Approximation for Weighted Korobov Spaces on Classical and Quantum Computers
quant-phE. Novak, I. H. Sloan, H. Wozniakowski
The paper studies quantum complexity, tractability, and strong tractability for high dimensional multivariate approximation. We study a space of functions important in many applications. A function space is weighted if certain variables are more important than others; the weights show the relative importance of the variables. In an unweighted space all varia