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Ends of iterated function systemsMar 06 2014Guided by classical concepts, we define the notion of \emph{ends} of an iterated function system and prove that the number of ends is an upper bound for the number of nondegenerate components of its attractor. The remaining isolated points are then linked ... More

The homotopy dimension of codiscrete subsets of the 2-sphereMar 03 2006We characterize those planar Peano continua that are homotopy equivalent to 1-dimensional sets. While many planar Peano continua are not homotopically 1-dimensional, we prove that each has fundamental group that embeds in the fundamental group of a 1-dimensional ... More

A note on automatic continuityOct 13 2017We present new results regarding automatic continuity, unifying some diagonalization concepts that have been developed over the years. For example, any homomorphism from a completely metrizable topological group to Thompson's group $F$ has open kernel. ... More

Some anomalous examples of lifting spacesAug 02 2017An inverse limit of a sequence of covering spaces over a given space $X$ is not, in general, a covering space over $X$ but is still a lifting space, i.e. a Hurewicz fibration with unique path lifting property. Of particular interest are inverse limits ... More

Self-affine ManifoldsFeb 12 2014Nov 09 2015This paper studies closed 3-manifolds which are the attractors of a system of finitely many affine contractions that tile $\mathbb{R}^3$. Such attractors are called self-affine tiles. Effective characterization and recognition theorems for these 3-manifolds ... More

Commensurators and Quasi-Normal SubgroupsDec 29 2009We say A is a quasi-normal subgroup of the group G if the commensurator of A in G is all of G. We develop geometric versions of commensurators in finitely generated groups. In particular, g is an element of the commensurator of A in G iff the Hausdorff ... More

Archipelago groupsOct 30 2014The classical archipelago is a non-contractible subset of $\mathbb{R}^3$ which is homeomorphic to a disk except at one non-manifold point. Its fundamental group, $\mathcal{A}$, is the quotient of the topologist's product of $\mathbb Z$, the fundamental ... More

On the First Homology of Peano ContinuaSep 23 2015We show that the first homology group of a locally connected compact metric space is either uncountable or is finitely generated. This is related to Shelah's well-known result which shows that the fundamental group of such a space satisfies a similar ... More

Geometry of compact lifting spacesJan 07 2019We study a natural generalization of inverse systems of finite regular covering spaces. A limit of such a system is a fibration whose fibres are profinite topological groups. However, as shown in a previous paper (Conner-Herfort-Pavesic: Some anomalous ... More

The Geometry and Fundamental Groups of Solenoid ComplementsDec 01 2012When a solenoid is embedded in three space, its complement is an open three manifold. We discuss the geometry and fundamental groups of such manifolds, and show that the complements of different solenoids (arising from different inverse limits) have different ... More

A rank 18 Waring decomposition of $sM_{\langle 3\rangle}$ with 432 symmetriesNov 15 2017The recent discovery that the exponent of matrix multiplication is determined by the rank of the symmetrized matrix multiplication tensor has invigorated interest in better understanding symmetrized matrix multiplication. I present an explicit rank 18 ... More

Violating Bell's inequality with remotely-connected superconducting qubitsAug 09 2018Oct 17 2018Quantum communication relies on the efficient generation of entanglement between remote quantum nodes, due to entanglement's key role in achieving and verifying secure communications. Remote entanglement has been realized using a number of different probabilistic ... More

Phonon-mediated quantum state transfer and remote qubit entanglementMar 13 2019Phonons, and in particular surface acoustic wave phonons, have been proposed as a means to coherently couple distant solid-state quantum systems. Recent experiments have shown that superconducting qubits can control and detect individual phonons in a ... More

Evidence for negative thermal expansion in the superconducting precursor phase SmFeAsOFeb 23 2018The fluorine-doped rare-earth iron oxypnictide series SmFeAsO$_{1-x}$F$_x$ (0 $\leq x \leq$ 0.10) was investigated with high resolution powder x-ray scattering. In agreement with previous studies, the parent compound SmFeAsO exhibits a tetragonal-to-orthorhombic ... More

Itinerant Antiferromagnetism in FeMnP0.8Si0.2 Single CrystalsJul 01 2015Compounds based on the Fe2P structure have continued to attract interest because of the interplay between itinerant and localized magnetism in a non-centrosymmetric crystal structure, and because of the recent developments of these materials for magnetocaloric ... More

Performance of the STACEE Atmospheric Cherenkov TelescopeOct 17 2000The Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE) is located at the National Solar Thermal Test Facility of Sandia National Laboratories in Albuquerque, New Mexico, USA. The field of solar tracking mirrors (heliostats) around a central ... More

Evidence for a pulsar wind nebula in the Type Ib-peculiar supernova SN 2012auSep 04 2018We present an optical spectrum of the energetic Type Ib supernova (SN) 2012au obtained at an unprecedented epoch of 6.2 years after explosion. Forbidden transition emission lines of oxygen and sulfur are detected with expansion velocities of 2300 km/s. ... More

Inverse Limits of Finite Rank Free GroupsMay 02 2011Aug 03 2011We will show that all inverse limits of finite rank free groups index by the natural numbers are isomorphic either to a finite rank free group or to a fixed universal group. In other words, any inverse system of finite rank free groups which is not equivalent ... More

Commensurated subgroups, semistability and simple connectivity at infinityJan 13 2012A subgroup Q is commensurated in a group G if each G conjugate of Q intersects Q in a group that has finite index in both Q and the conjugate. So commensurated subgroups are similar to normal subgroups. Semistability and simple connectivity at infinity ... More

High Energy Gamma-Ray Observations of the Crab Nebula and Pulsar with the Solar Tower Atmospheric Cherenkov Effect ExperimentJun 21 2000The Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE) is a new ground-based atmospheric Cherenkov telescope for gamma-ray astronomy. STACEE uses the large mirror area of a solar heliostat facility to achieve a low energy threshold. A prototype ... More

The STACEE-32 Ground Based Gamma-ray DetectorMay 29 2002We describe the design and performance of the Solar Tower Atmospheric Cherenkov Effect Experiment detector in its initial configuration (STACEE-32). STACEE is a new ground-based gamma ray detector using the atmospheric Cherenkov technique. In STACEE, ... More

Some non-Koszul algebras from rational homotopy theoryJul 17 2014Feb 17 2015The McCool group, denoted $P\Sigma_n$, is the group of pure symmetric automorphisms of a free group of rank $n$. The cohomology algebra $H^*(P\Sigma_n, \mathbb{Q})$ was determined by Jensen, McCammond and Meier. We prove that $H^*(P\Sigma_n, \mathbb{Q})$ ... More

From Twisted Quantum Loop Algebras to Twisted YangiansMay 14 2015We prove how the Yangian of $\mathfrak{gl}_N$ in its RTT presentation and Olshanski's twisted Yangians for the orthogonal and symplectic Lie algebras can be obtained by a degeneration process from the corresponding quantum loop algebra and some of its ... More

Local topological properties of asymptotic cones of groupsOct 16 2012We define a local analogue to Gromov's loop division property which is use to give a sufficient condition for an asymptotic cone of a complete geodesic metric space to have uncountable fundamental group. As well, this property is used to understand the ... More

Concerning Fundamental Groups of Locally Connected Subsets of the PlaneMay 02 2011May 17 2013We show that every homomorphism from a one-dimensional Peano continuum to a planar Peano continuum is induced by a continuous map up to conjugation. We then prove that the topological structure of the space of points at which a planar Peano continuum ... More

Classification, Koszulity and Artin-Schelter Regularity of some Graded Twisted Tensor ProductsNov 25 2018Let $\mathbb{k}$ be an algebraically closed field. We classify all of the quadratic twisted tensor products $A \otimes_{\tau} B$ in the cases where $(A, B) = (\mathbb{k}[x], \mathbb{k}[y])$ and $(A, B) = (\mathbb{k}[x, y], \mathbb{k}[z])$. We determine ... More

The Koszul Property for Graded Twisted Tensor ProductsAug 08 2017Jun 04 2018Let $k$ be a field. Let $A$ and $B$ be connected $N$-graded $k$-algebras. Let $C$ denote a twisted tensor product of $A$ and $B$ in the category of connected $N$-graded $k$-algebras. The purpose of this paper is to understand when $C$ possesses the Koszul ... More

Low Surface Brightness Radio Structure in the Field of Gravitational Lens 0957+561Aug 19 1997We have produced deep radio maps of the double quasar 0957+561 from multiple-epoch VLA observations. To achieve high sensitivity to extended structure we have re-reduced the best available 1.6 GHz observations and have combined 5 GHz data from multiple ... More

Quantum control of surface acoustic wave phononsApr 19 2018The superposition of quantum states is one of the hallmarks of quantum physics, and clear demonstrations of superposition have been achieved in a number of quantum systems. However, mechanical systems have remained a challenge, with only indirect demonstrations ... More

Control of the third dimension in copper-based square-lattice antiferromagnetsMar 01 2016Using a mixed-ligand synthetic scheme, we create a family of quasi-two-dimensional antiferromagnets, namely, [Cu(HF$_2$)(pyz)$_2$]ClO$_4$ [pyz = pyrazine], [Cu$L_2$(pyz)$_2$](ClO$_4$)$_2$ [$L$ = pyO = pyridine-N-oxide and 4-phpyO = 4-phenylpyridine-N-oxide. ... More

Vortex lock-in transition and evidence for transitions among commensurate kinked vortex configurations in single-layered Fe arsenidesMar 12 2013We report an angle-dependent study of the magnetic torque $\tau(\theta)$ within the vortex state of single-crystalline LaO$_{0.9}$F$_{0.1}$FeAs and SmO$_{0.9}$F$_{0.1}$FeAs as a function of both temperature $T$ and magnetic field $H$. Sharp peaks are ... More

The Gravitationally-Lensed Radio Source MG0751+2716Feb 21 1997May 15 1997We report the discovery of a new gravitationally lensed radio source. Radio maps of MG0751+2716 show four lensed images, which, at higher resolution, are resolved into long arcs of emission. A group of galaxies is present in optical images, including ... More

Towards Controlling Refinements of StatechartsMar 25 2015In incremental development strategies, modelers frequently refine Statecharts models to satisfy requirements and changes. Although several solutions exist to the problem of Statecharts refinement, they provide such levels of freedom that a statechart ... More

Growth and Characterization of Ce- Substituted Nd2Fe14B Single CrystalsAug 31 2015Single crystals of (Nd1-xCex)2Fe14B are grown out of Fe-(Nd,Ce) flux. Chemical and structural analysis of the crystals indicates that (Nd1-xCex)2Fe14B forms a solid solution until at least x = 0.38 with a Vegard-like variation of the lattice constants ... More

Deep Convolutional Neural Networks for Noise Detection in ECGsOct 05 2018Mobile electrocardiogram (ECG) recording technologies represent a promising tool to fight the ongoing epidemic of cardiovascular diseases, which are responsible for more deaths globally than any other cause. While the ability to monitor one's heart activity ... More

The Type II-Plateau Supernova 2017eaw in NGC 6946 and Its Red Supergiant ProgenitorMar 09 2019We present extensive optical photometric and spectroscopic observations, from 4 to 482 days after explosion, of the Type II-plateau (II-P) supernova (SN) 2017eaw in NGC 6946. SN 2017eaw is a normal SN II-P intermediate in properties between, for example, ... More

Monte Carlo simulation of a very high resolution thermal neutron detector composed of glass scintillator microfibersJun 11 2016In order to develop a high spatial resolution (micron level) thermal neutron detector, a detector assembly composed of cerium doped lithium glass microfibers, each with a diameter of 1\,$\mu$m, is proposed, where the neutron absorption location is reconstructed ... More

Noncommutative Knörrer periodicity and noncommutative Kleinian singularitiesSep 18 2018Feb 25 2019We establish a version of Kn\"{o}rrer's Periodicity Theorem in the context of noncommutative invariant theory. Namely, let $A$ be a left noetherian AS-regular algebra, let $f$ be a normal and regular element of $A$ of positive degree, and take $B=A/(f)$. ... More

Noncommutative Knörrer periodicity and noncommutative Kleinian singularitiesSep 18 2018We establish a version of Kn\"{o}rrer's Periodicity Theorem in the context of noncommutative invariant theory. Namely, let $A$ be a left noetherian AS-regular algebra, let $f$ be a normal and regular element of $A$ of positive degree, and take $B=A/(f)$. ... More

Periodic free resolutions from twisted matrix factorizationsJul 31 2013The notion of a matrix factorization was introduced by Eisenbud in the commutative case in his study of bounded (periodic) free resolutions over complete intersections. In this work, we extend the notion of (homogeneous) matrix factorizations to regular ... More

On small homotopies of loopsDec 11 2007Two natural questions are answered in the negative: (1) If a space has the property that small nulhomotopic loops bound small nulhomotopies, then are loops which are limits of nulhomotopic loops themselves nulhomotopic? (2) Can adding arcs to a space ... More

Finiteness conditions on the Yoneda algebra of a monomial algebraOct 11 2012Let A be a connected graded noncommutative monomial algebra. We associate to A a finite graph \Gamma(A) called the CPS graph of A. Finiteness properties of the Yoneda algebra Ext_A(k,k) including Noetherianity, finite GK dimension, and finite generation ... More

Eliciting the Endowment Effect under Assigned OwnershipSep 22 2018Oct 04 2018In this study we present evidence that endowment effect can be elicited merely by assigned ownership. Using Google Customer Survey, we administered a survey were participants (n=495) were randomly split into 4 groups. Each group was assigned ownership ... More

A geometric study of Strassen's asymptotic rank conjecture and its variantsNov 13 2018We establish basic information about the set of tight tensors, the tensors with continuous regular symmetry. Our motivation is Strassen's astounding asymptotic rank conjecture that the asymptotic rank of any tight tensor is minimal. In particular, we ... More

Magnetic order in the S=1/2 two-dimensional molecular antiferromagnet, copper pyrazine perchlorate Cu(Pz)_2(ClO_4)_2Dec 13 2006We present an investigation of magnetic ordering in the two-dimensional S=1/2 quantum magnet Cu(Pz)_2(ClO_4)_2 using specific heat and zero field muon-spin relaxation (\mu^+SR). The magnetic contribution to the specific heat is consistent with an exchange ... More

First dark matter search results from a 4-kg CF$_3$I bubble chamber operated in a deep underground siteApr 13 2012Sep 19 2012New data are reported from the operation of a 4.0 kg CF$_{3}$I bubble chamber in the 6800-foot-deep SNOLAB underground laboratory. The effectiveness of ultrasound analysis in discriminating alpha-decay background events from single nuclear recoils has ... More

Energy Harvesting with a Liquid-Metal Microfluidic Influence MachineMar 06 2018We describe and demonstrate a new energy harvesting technology based on a microfluidic realization of a Wimshurst influence machine. The prototype device converts the mechanical energy of a pressure-driven flow into electrical energy, using a multiphase ... More

Branching ratio measurements of the 7.12-MeV state in 16OOct 25 2004Knowledge of the gamma-ray branching ratios of the 7.12-MeV state of 16O is important for the extrapolation of the 12C(a,g)16O cross section to astrophysical energies. Ground state transitions provide most of the 12C(a,g)16O total cross section while ... More

Phenomenology of the Two Higgs Doublet Sector of a Quark-Lepton Symmetric ModelMar 23 1994In the simplest examples of models with a discrete quark-lepton symmetry, an electroweak symmetry breaking sector with more than one Higgs doublet is necessary to obtain the correct mass relations between quarks and leptons. A two Higgs doublet model ... More

Anticipated synchronization and the predict-prevent control method in the FitzHugh-Nagumo model systemJan 05 2012We study the synchronization region of two unidirectionally coupled, in a master-slave configuration, FitzHugh-Nagumo systems under the influence of external forcing terms. We observe that anticipated synchronization is robust to the different types of ... More

Probing halo nucleus structure through intermediate energy elastic scatteringJun 30 1999This work addresses the question of precisely what features of few body models of halo nuclei are probed by elastic scattering on protons at high centre-of-mass energies. Our treatment is based on a multiple scattering expansion of the proton-projectile ... More

Distance-Redshift in Inhomogeneous $Omega_0=1$ Friedmann-Lemaitre-Robertson-Walker CosmologyNov 08 2000Jun 18 2001Distance--redshift relations are given in terms of associated Legendre functions for partially filled beam observations inspatially flat Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmologies. These models are dynamically pressure-free, flat FLRW on large ... More

Ring-Like Structure in the Radio Lobe of MG0248+0641Aug 16 1997Oct 01 1997We present radio and optical observations of MG0248+0641, which contains a kiloparsec-scale ring-like structure in one of its radio lobes. The radio observations show a typical core-double morphology: a central core between two lobes, each of which has ... More

Search for domain wall dark matter with atomic clocks on board global positioning system satellitesApr 22 2017Oct 30 2017Cosmological observations indicate that 85% of all matter in the Universe is dark matter (DM), yet its microscopic composition remains a mystery. One hypothesis is that DM arises from ultralight quantum fields that form macroscopic objects such as topological ... More

Low-Energy Scattering of Black Holes and p-branes in String TheoryDec 18 1995We discuss the low-energy dynamics of generalized extremal higher membrane black hole solutions of string theory and higher membrane theories following Manton's prescription for multi-soliton solutions. A flat metric is found for those solutions which ... More

A Ray-Tracing Model of the Vela PulsarJan 19 2001In the relativistic plasma surrounding a pulsar, a subluminal ordinary-mode electromagnetic wave will propagate along a magnetic field line. After some distance, it can break free of the field line and escape the magnetosphere to reach an observer. We ... More

Frame-Independence of Exclusive Amplitudes in the Light-Front QuantizationMar 31 2000While the particle-number-conserving convolution formalism established in the Drell-Yan-West reference frame is frequently used to compute exclusive amplitudes in the light-front quantization, this formalism is limited to only those frames where the light-front ... More

Numerical linear stability analysis of round galactic disksApr 10 1997The method originally developed by Kalnajs for the numerical linear stability analysis of round galactic disks is implemented in the regimes of non-analytic transformations between position space and angle-action space, and of vanishing growth rates. ... More

The rules of coherence and other habitsOct 22 2003Physics and mathematics are difficult enough without the aditional burden of bad habits. In this article, we examine some helpful habits that tend to be underemphasized by many physics teachers (mainly because they seem so obvious!).

Subexponential group cohomology and the K-theory of Lafforgue's algebra A_{max}(pi)Dec 07 2012We show that for any finitely generated group G, group cohomology classes represented by cocycles of subexponential growth are extendable over the topological K-groups of the Lafforgue algebra associated to G.

Beating oscillation and Fano resonance in the laser assisted electron transmission through graphene δ- function magnetic barriersJan 29 2016We investigate theoretically the transmission of electrons through a pair of {\delta}- function magnetic barriers in graphene in presence of external monochromatic, linearly polarised and CW laser field. The transmission coefficients are calculated in ... More

Spin orbit splitting of the photon induced Fano Resonance in an oscillating graphene electrostatic barrierAug 12 2015We investigate theoretically the effect of a time dependent oscillating potential on the transport property of the Dirac Fermion through a monolayer graphene electrostatic barrier under the influence of the Rashba spin orbit interaction. The time dependent ... More

Ergodic Properties of Microcanonical ObservablesSep 12 1997The problem of the existence of a Strong Stochasticity Threshold in the FPU-beta model is reconsidered, using suitable microcanonical observables of thermodynamic nature, like the temperature and the specific heat. Explicit expressions for these observables ... More

On the Initial Mass Function and tilt of the Fundamental Plane of massive early-type galaxiesDec 20 2009Dec 23 2009We investigate the most plausible stellar Initial Mass Function (IMF) and the main origin of the tilt of the Fundamental Plane (FP) for old, massive early-type galaxies. We consider a sample of 13 bright galaxies of the Coma cluster and combine our results ... More

Knowledge transfer in a tourism destination: the effects of a network structureMay 17 2009May 23 2009Tourism destinations have a necessity to innovate to remain competitive in an increasingly global environment. A pre-requisite for innovation is the understanding of how destinations source, share and use knowledge. This conceptual paper examines the ... More

Wavy Horizons?Sep 14 1998We describe the application of a gravity wave-generating technique to certain higher dimensional black holes. We find that the induced waves generically destroy the event horizon producing parallelly propagated curvature singularities.

Equações diferenciais pantográficas: retardo proporcionalMay 24 2014We present initially the motivation, definition and basic properties of differential equations with proportional delay. In the last Section we present open problems.

Cosmic confusionDec 30 1994We propose to minimise the cosmic confusion between Gaussian and non Gaussian theories by investigating the structure in the m's for each multipole of the cosmic radiation temperature anisotropies. We prove that Gaussian theories are (nearly) the only ... More

Multiplicative renormalizability of gluon and ghost propagators in QCDJun 04 2001We reformulate the coupled set of continuum equations for the renormalized gluon and ghost propagators in QCD, such that the multiplicative renormalizability of the solutions is manifest, independently of the specific form of full vertices and renormalization ... More

Multiplicative renormalizability and quark propagatorFeb 07 2002Jul 04 2002The renormalized Dyson-Schwinger equation for the quark propagator is studied, in Landau gauge, in a novel truncation which preserves multiplicative renormalizability. The renormalization constants are formally eliminated from the integral equations, ... More

Abundance Profiles in Disk Galaxies from NebulaeJan 13 1998Galactic and extragalactic abundance studies of H II regions, planetary nebulae, and supernova remnants are compiled and their implications briefly reviewed. Galaxy global metallicity appears to be related directly to total mass and morphology, while ... More

Element Yields of Intermediate-Mass StarsMay 27 2003Intermediate mass stars occupy the mass range between 0.8-8 solar masses. In this review, evolutionary models of these stars from numerous sources are compared in terms of their input physics and predicted yields. In particular, the results of Renzini ... More

Second central extension in Galilean covariant field theoryMar 21 2002The second central extension of the planar Galilei group has been alleged to have its origin in the spin variable. This idea is explored here by considering local Galilean covariant field theory for free fields of arbitrary spin. It is shown that such ... More

Cutoff dependence of the Casimir effectMar 22 2000The problem of calculating the Casimir force on two conducting planes by means of the stress tensor is examined. The evaluation of this quantity is carried out using an explicit regularization procedure which has its origin in the underlying (2+1) dimensional ... More

Non-thermalizability of a Quantum Field TheoryFeb 02 1998The problem of understanding the role of large gauge transformations in thermal field theories has recently inspired a number of studies of a one dimensional field theory. Such work has led to the conclusion that gauge invariance is restored only when ... More

Comment on Internal Frame Dragging and a Global Analog of the Aharonov-Bohm EffectSep 30 1992It is shown that AB-like cross sections can be obtained from symmetry breaking which does not require infinite energy, angular dependence in the symmetry breaking term, or a nontrivial $Z_2$ charge.

Spin and Statistics in Galilean Covariant Field TheoryMar 04 2004The existence of a possible connection between spin and statistics is explored within the framework of Galilean covariant field theory. To this end fields of arbitrary spin are constructed and admissible interaction terms introduced. By explicitly solving ... More

Perturbative Expansion in the Galilean Invariant Spin One-Half Chern-Simons Field TheoryMar 12 1997A Galilean Chern-Simons field theory is formulated for the case of two interacting spin-1/2 fields of distinct masses M and M'. A method for the construction of states containing N particles of mass M and N' particles of mass M' is given which is subsequently ... More

Comment on "Statistical Mechanics of Non-Abelian Chern-Simons Particles"Dec 11 1995The second virial coefficient for non-Abelian Chern-Simons particles is recalculated. It is shown that the result is periodic in the flux parameter just as in the Abelian theory.

Unification of the Soluble Two-dimensional vector coupling modelsSep 07 1994The general theory of a massless fermion coupled to a massive vector meson in two dimensions is formulated and solved to obtain the complete set of Green's functions. Both vector and axial vector couplings are included. In addition to the boson mass and ... More

Comment on Gauge-Independent Analysis of Chern-Simons Theory with Matter CouplingOct 05 1992It is shown that a recently proposed relativistic field theory of anyons is mathematically flawed and also does not satisfy reasonable criteria for such a theory.

Numerical study of blow-up in solutions to generalized Korteweg-de Vries equationsJul 02 2013Nov 14 2014We present a detailed numerical study of solutions to general Korteweg-de Vries equations with critical and supercritical nonlinearity. We study the stability of solitons and show that they are unstable against being radiated away and blow-up. In the ... More

Concept of Quaternion Mass for Wave-Particle Duality : A Novel ApproachMay 07 2003Mass is in the central theme everywhere from atom to galaxy. But what is mass ? Is it scalar or vector ? Apparently it appears that mass is scalar; but relativistic mass is velocity dependent and moving mass such as photon is vector boson. In the present ... More

Evidences of an innermost stable bound orbit predicted by general relativity from the amplitude of the twin-peak quasi-periodic oscillationsApr 09 2015The twin-peak high-frequency quasi-periodic oscillations (HF QPOs), observed in the power spectra of low-mass X-ray binaries, might carry relevant clues about the physics laws reigning close to a compact object. Their frequencies are typical of the orbital ... More

Why Two Renormalization Groups are Better than OneNov 09 1996The advantages of using more than one renormalization group (RG) in problems with more than one important length scale are discussed. It is shown that: i) using different RG's can lead to complementary information, i.e. what is very difficult to calculate ... More

Massive MIMO Systems: Signal Processing Challenges and Research TrendsOct 28 2013This article presents a tutorial on multiuser multiple-antenna wireless systems with a very large number of antennas, known as massive multi-input multi-output (MIMO) systems. Signal processing challenges and future trends in the area of massive MIMO ... More

Robust Low-Rank LCMV Beamforming Algorithms Based on Joint Iterative Optimization StrategiesFeb 10 2013This chapter presents reduced-rank linearly constrained minimum variance (LCMV) algorithms based on the concept of joint iterative optimization of parameters. The proposed reduced-rank scheme is based on a constrained robust joint iterative optimization ... More

Ultracold atomic Fermi-Bose mixtures in bichromatic optical dipole traps: a novel route to study fermion superfluidityMar 24 2004The study of low density, ultracold atomic Fermi gases is a promising avenue to understand fermion superfluidity from first principles. One technique currently used to bring Fermi gases in the degenerate regime is sympathetic cooling through a reservoir ... More

Temperature dependent band structure of the Kondo insulatorJan 08 1998We present a Qantum Monte Carlo (QMC) study of the temperature dependent dynamics of the Kondo insulator. Working at the so-called symmetrical point allows to perform minus-sign free QMC simulations and thus reach temperatures of less than 1% of the conduction ... More

Theory of ARPES intensities from the CuO$_2$ planeSep 03 2001We present a theory for the photon energy and polarization dependence of ARPES intensities from the CuO$_2$ plane in the framework of strong correlation models. We show that for electric field vector in the CuO$_2$ plane the `radiation characteristics' ... More

Fermiology of a 1D heavy electron metalDec 21 1998We present a Quantum Monte Carlo (QMC) study of the 1D Kondo lattice at non-integer filling, i.e. a one-dimensional version of a heavy electron metal. For this special system the minus-sign problem turns out to be strongly reduced, which allows QMC simulations ... More

Nature of the Fulde-Ferrell-Larkin-Ovchinnikov phases at low temperature in 2 dimensionsJun 23 2003We investigate, mostly analytically, the nature of the Fulde-Ferrell- Larkin-Ovchinnikov superfluid phases for an isotropic two-dimensional superconductor, which is relevant for the experimental observation of these phases. We show that there is, in the ... More

Transition to Fulde-Ferrel-Larkin-Ovchinnikov phases near the tricritical point : an analytical studyMar 01 2002We explore analytically the nature of the transition to the Fulde-Ferrel-Larkin-Ovchinnikov superfluid phases in the vicinity of the tricritical point, where these phases begin to appear. We make use of an expansion of the free energy up to an overall ... More

Construction and Recognition of Hyperbolic 3-Manifolds with Geodesic BoundarySep 03 2001We extend to the context of hyperbolic 3-manifolds with geodesic boundary Thurston's approach to hyperbolization by means of geometric triangulations. In particular, we introduce moduli for (partially) truncated hyperbolic tetrahedra, and we discuss consistency ... More

Bosonisation and Soldering of Dual Symmetries in Two and Three DimensionsSep 15 1997Oct 30 1997We develop a technique that solders the dual aspects of some symmetry following from the bosonisation of two distinct fermionic models, thereby leading to new results which cannot be otherwise obtained. Exploiting this technique, the two dimensional chiral ... More

Lattice Monte Carlo Data versus Perturbation TheoryOct 15 1996The differences between lattice Monte Carlo data and perturbation theory are usually associated with the ``bad'' behaviour of the bare lattice coupling g_0 due to the effects of large (and unknown) higher order coefficients in the g_0 perturbative series. ... More

Towards extracting the best possible results from NOvAMay 02 2016The NuMI Off-Axis $\nu_{e}$ Appearance (NO$\nu$A) is the currently running leading long-baseline neutrino oscillation experiment, whose main physics goal is to explore the current issues in the neutrino sector, such as determination of the neutrino mass ... More

Linear Systems of Plane Curves with Base Points of Equal MultiplicityApr 03 1998In this article we address the problem of computing the dimension of the space of plane curves of degree $d$ with $n$ general points of multiplicity $m$. A conjecture of Harbourne and Hirschowitz implies that when $d \geq 3m$, the dimension is equal to ... More

Generating Converging Bounds to the (Complex) Discrete States of the $P^2 + iX^3 + iαX$ HamiltonianApr 26 2001The Eigenvalue Moment Method (EMM), Handy (2001), Handy and Wang (2001)) is applied to the $H_\alpha \equiv P^2 + iX^3 + i\alpha X$ Hamiltonian, enabling the algebraic/numerical generation of converging bounds to the complex energies of the $L^2$ states, ... More

Generating Converging Eigenenergy Bounds for the Discrete States of the -ix^3 Non-Hermitian PotentialApr 26 2001Recent investigations by Bender and Boettcher (Phys. Rev. Lett 80, 5243 (1998)) and Mezincescu (J. Phys. A. 33, 4911 (2000)) have argued that the discrete spectrum of the non-hermitian potential $V(x) = -ix^3$ should be real. We give further evidence ... More