Search results for "Names"

showing 10 items of 6843 documents

Approximate energy functionals for one-body reduced density matrix functional theory from many-body perturbation theory

2018

We develop a systematic approach to construct energy functionals of the one-particle reduced density matrix (1RDM) for equilibrium systems at finite temperature. The starting point of our formulation is the grand potential $\Omega [\mathbf{G}]$ regarded as variational functional of the Green's function $G$ based on diagrammatic many-body perturbation theory and for which we consider either the Klein or Luttinger-Ward form. By restricting the input Green's function to be one-to-one related to a set on one-particle reduced density matrices (1RDM) this functional becomes a functional of the 1RDM. To establish the one-to-one mapping we use that, at any finite temperature and for a given 1RDM $\…

Grand potentialSolid-state physicsComplex systemFOS: Physical sciencesdensity matrix functional theory01 natural sciencesCondensed Matter - Strongly Correlated Electronssymbols.namesakePhysics - Chemical Physics0103 physical sciencesSDG 7 - Affordable and Clean Energy010306 general physicsMathematical physicsEnergy functionalChemical Physics (physics.chem-ph)PhysicsQuantum Physics/dk/atira/pure/sustainabledevelopmentgoals/affordable_and_clean_energyStrongly Correlated Electrons (cond-mat.str-el)010304 chemical physicstiheysfunktionaaliteoriamany-body perturbation theory16. Peace & justiceCondensed Matter PhysicsStationary pointElectronic Optical and Magnetic MaterialsCondensed Matter - Other Condensed Matterapproximate energy functionalssymbolsReduced density matrixapproksimointiQuantum Physics (quant-ph)Hamiltonian (quantum mechanics)Ground stateOther Condensed Matter (cond-mat.other)The European Physical Journal B
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A Gravitational-wave Measurement of the Hubble Constant Following the Second Observing Run of Advanced LIGO and Virgo

2021

This paper presents the gravitational-wave measurement of the Hubble constant (H 0) using the detections from the first and second observing runs of the Advanced LIGO and Virgo detector network. The presence of the transient electromagnetic counterpart of the binary neutron star GW170817 led to the first standard-siren measurement of H 0. Here we additionally use binary black hole detections in conjunction with galaxy catalogs and report a joint measurement. Our updated measurement is H 0 = km s-1 Mpc-1 (68.3% of the highest density posterior interval with a flat-in-log prior) which is an improvement by a factor of 1.04 (about 4%) over the GW170817-only value of km s-1 Mpc-1. A significant …

Gravitacióneutron star: binarycosmological model010504 meteorology & atmospheric sciencesAstronomyGravitational Waves Hubble constant O2 LIGO Virgodetector: network01 natural sciencesCosmologyGeneral Relativity and Quantum CosmologyLIGOdark energy010303 astronomy & astrophysicsQCPhysicsSettore FIS/01Hubble constantSettore FIS/05CATALOGPhysical Sciencessymbols[PHYS.GRQC]Physics [physics]/General Relativity and Quantum Cosmology [gr-qc]Astrophysics - Cosmology and Nongalactic AstrophysicsCosmology and Nongalactic Astrophysics (astro-ph.CO)DATA RELEASECOSMOLOGICAL PARAMETERSFOS: Physical sciencesO2General Relativity and Quantum Cosmology (gr-qc)Astrophysics::Cosmology and Extragalactic AstrophysicsAstronomy & AstrophysicsLUMINOSITY FUNCTIONSgravitational radiation: direct detectionGravitational-wave astronomy1STArticleelectromagnetic field: productionsymbols.namesakeBinary black hole0103 physical sciencesDISTRIBUTIONS/dk/atira/pure/subjectarea/asjc/1900/1912K-CORRECTIONSSDG 7 - Affordable and Clean EnergyAstrophysiqueSTFC0105 earth and related environmental sciencesGravitational Waves/dk/atira/pure/sustainabledevelopmentgoals/affordable_and_clean_energyScience & TechnologyGravitational waveVirgoAstronomyRCUKAstronomy and Astrophysicscosmology; gravitational waves; Hubble constant310 Galaxies and CosmologyLIGOGalaxyEVOLUTIONDewey Decimal Classification::500 | Naturwissenschaften::520 | Astronomie Kartographiegravitational radiation detectorVIRGOblack hole: binarySpace and Planetary Science[SDU]Sciences of the Universe [physics]DENSITYgravitational radiation: emissionDark energyAstronomiaddc:520/dk/atira/pure/subjectarea/asjc/3100/3103galaxyGravitational wave astronomy[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]Hubble's lawThe Astrophysical Journal
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Soldner, Einstein, gravitational light deflection and factors of two

2021

GravitationPhysicssymbols.namesakeClassical mechanics510 MathematicsDeflection (physics)General relativity530 PhysicssymbolsGeneral Physics and Astronomy510 MathematikEinstein530 Physik
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Einstein’s gravitational field equations and the bianchi identities

2002

In his highly acclaimed biography of Einstein, Abraham Pais gave a fairly detailed analysis of the many difficulties his hero had to overcome in November 1915 before he finally arrived at generally covariant equations for gravitation (Pais 1982, 250–261).

GravitationPhysicssymbols.namesakeHistory and Philosophy of ScienceGravitational fieldGeneral MathematicssymbolsHEROCovariant transformationEinsteinMathematical physicsThe Mathematical Intelligencer
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Incremental Gaussian Discriminant Analysis based on Graybill and Deal weighted combination of estimators for brain tumour diagnosis

2011

In the last decade, machine learning (ML) techniques have been used for developing classifiers for automatic brain tumour diagnosis. However, the development of these ML models rely on a unique training set and learning stops once this set has been processed. Training these classifiers requires a representative amount of data, but the gathering, preprocess, and validation of samples is expensive and time-consuming. Therefore, for a classical, non-incremental approach to ML, it is necessary to wait long enough to collect all the required data. In contrast, an incremental learning approach may allow us to build an initial classifier with a smaller number of samples and update it incrementally…

Graybill-Deal estimatorDatabases FactualComputer sciencePopulation-based incremental learningGaussianTraining setsHealth InformaticsMachine learningcomputer.software_genreIncremental algorithmPersonalizationsymbols.namesakeAutomatic brain tumour diagnosisArtificial IntelligenceNumber of samplesMachine learningMagnetic resonance spectroscopyHumansPreprocessIncremental learningTraining setbusiness.industryBrain NeoplasmsBrain tumoursEstimatorComputational BiologyPattern recognitionLinear discriminant analysisMagnetic Resonance ImagingDiscriminant analysisTranslational research Tissue engineering and pathology [ONCOL 3]Graybill–Deal estimatorComputer Science ApplicationsGaussiansMagnetic resonanceFISICA APLICADAIncremental learningsymbolsEmpirical resultsArtificial intelligencebusinessClassifier (UML)computerEstimationAlgorithmsJournal of Biomedical Informatics
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Deperturbation treatment of theAΣ+1–bΠ3complex of NaRb and prospects for ultracold molecule formation inXΣ+1(v=0;J=0)

2007

High resolution Fourier transform spectra (FTS) of laser induced fluorescence (LIF) of $C\phantom{\rule{0.2em}{0ex}}^{1}\ensuremath{\Sigma}^{+};D\phantom{\rule{0.2em}{0ex}}^{1}\ensuremath{\Pi}\ensuremath{\rightarrow}A\phantom{\rule{0.2em}{0ex}}^{1}\ensuremath{\Sigma}^{+}--b\phantom{\rule{0.2em}{0ex}}^{3}\ensuremath{\Pi}$ and $A\phantom{\rule{0.2em}{0ex}}^{1}\ensuremath{\Sigma}^{+}--b\phantom{\rule{0.2em}{0ex}}^{3}\ensuremath{\Pi}\ensuremath{\rightarrow}X\phantom{\rule{0.2em}{0ex}}^{1}\ensuremath{\Sigma}^{+}$ transitions in ${\mathrm{Na}}^{85}\mathrm{Rb}$ and ${\mathrm{Na}}^{87}\mathrm{Rb}$ were obtained. An analysis of the direct LIF spectra together with the rotational relaxation satellite…

Ground levelPhysicssymbols.namesakeMolecule formationsymbolsState (functional analysis)Atomic physicsCoupling (probability)Radial coordinateHamiltonian (quantum mechanics)Wave functionAtomic and Molecular Physics and OpticsSpectral linePhysical Review A
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Group analysis and similarity solutions of the compressible boundary layer equations

1989

In this paper the application of Lie's methods to the equations of the laminar boundary layer is discussed. The momentum and energy equations in Prandtl's form are considered for a steady, viscous, compressible laminar flow with non zero pressure gradient, variable viscosity and thermal conductivity. Group analysis yields similarity solutions for given pressure distributions and particular values of the invariance group parameters (group classification). Crocco's transformation is obtained for the infinite-dimensional group of the Lie's algebra admitted by the equations.

Group (mathematics)Mechanical EngineeringMathematical analysisPrandtl numberLie groupLaminar flowCondensed Matter PhysicsBoundary layer thicknessSimilarity solutionPhysics::Fluid Dynamicssymbols.namesakeBoundary layerMechanics of MaterialsBlasius boundary layersymbolsMathematicsMeccanica
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Detecting the chaotic nature of advection in complex river flows

2012

In order to detect signatures of chaotic advection in river surface motion, surface buoys equipped with GPS were deployed in a field experiment in River Danube, Hungary. The buoys were released in the vicinity of groynes where complex mixing processes occur. A detailed analysis of the trajectories was carried out, focusing on the time evolution of the distance between buoy pairs. The analysis included the determination and comparison of local Lyapunov exponents and prediction times of finite-time hyperbolic behaviour, which is related to strong mixing. Despite of the small number of applied buoys we found evidence on Lagrangian chaos in the wake of a groyne field. In order to supplement the…

GroyneBuoyMeteorologyRiver hydraulics groyne (groin) chaotic mixing Lagrangian transport Particle Tracking Velocimetry (PTV)AdvectionSettore ICAR/02 - Costruzioni Idrauliche E Marittime E IdrologiaChaoticLyapunov exponentGeotechnical Engineering and Engineering GeologyGeodesyChaotic mixingsymbols.namesakeParticle tracking velocimetrysymbolsPhysics::Atmospheric and Oceanic PhysicsGeologyMixing (physics)Civil and Structural EngineeringPERIOD POLYTECH CIV ENG PERIODICA POLYTECHNICA-CIVIL ENGINEERING
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Zur R�ntgenidentifizierung unbekannter Leichen bei fortgeschrittenen postmortalen Ver�nderungen

1989

Die postmortalen Veranderungen an einer Wasserleiche und an einer Brandleiche waren so weit fortgeschritten, das die ublichen Identifizierungsmethoden versagen musten. Vergleichende rontgenologische Untersuchungen ermoglichten jedoch den sicheren Nachweis der Identitat. Der Erfolg beruhte auf der individuellen Variabilitat des Skelettsystems und seiner hohen Widerstandsfahigkeit gegenuber intravitalen und postmortalen Einflussen. Neben der hohen Aussagekraft sind einfache, schnelle Handhabung sowie Dokumentation — ohne Beeintrachtigung der Obduktion — weitere Vorteile der Rontgenidentifizierung. Die vorgestellten Falle zeigen zudem, das auch zehn Jahre alte intravitale Vergleichsbilder zur …

Gynecologysymbols.namesakemedicine.medical_specialtybusiness.industrysymbolsMedicineRoentgenAnatomybusinessPostmortem ChangesPathology and Forensic MedicineZeitschrift f�r Rechtsmedizin
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Investigations of Surface Forces between Gypsum Microcrystals in Air Using Atomic Force Microscopy

2000

This article introduces a new approach to the study of the interactions between gypsum faces in air. We have mounted a gypsum crystal on the end of a microcantilever to measure local forces (van der Waals, capillary forces, electrostatic) directly between two crystals. A systematic study with respect to the orientation of crystalline faces, relative humidity, and the duration of contact between crystals improves the understanding of the mechanism involved in the hardening of plaster in air. In dry air, a physicochemical process of matter transfer is added to the van der Waals forces to ensure the cohesion. Others force measurements were performed by varying the shape of the contact (interac…

GypsumSiliconChemistryCapillary actionSurface forcechemistry.chemical_elementMineralogySurfaces and Interfacesengineering.materialCondensed Matter PhysicsCrystalsymbols.namesakeElectrochemistryengineeringsymbolsHardening (metallurgy)General Materials ScienceWettingvan der Waals forceComposite materialSpectroscopyLangmuir
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