Search results for "Tonian"

showing 10 items of 802 documents

Calculation of excited-state properties using general coupled-cluster and configuration-interaction models.

2004

Using string-based algorithms excitation energies and analytic first derivatives for excited states have been implemented for general coupled-cluster (CC) models within CC linear-response (LR) theory which is equivalent to the equation-of-motion (EOM) CC approach for these quantities. Transition moments between the ground and excited states are also considered in the framework of linear-response theory. The presented procedures are applicable to both single-reference-type and multireference-type CC wave functions independently of the excitation manifold constituting the cluster operator and the space in which the effective Hamiltonian is diagonalized. The performance of different LR-CC/EOM-…

General Physics and AstronomyConfiguration interactionStationary pointchemistry.chemical_compoundsymbols.namesakeCoupled clusterAcetylenechemistryQuantum mechanicsExcited statesymbolsPhysical and Theoretical ChemistryAtomic physicsWave functionHamiltonian (quantum mechanics)ExcitationThe Journal of chemical physics
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Non-hermitian operator modelling of basic cancer cell dynamics

2018

We propose a dynamical system of tumor cells proliferation based on operatorial methods. The approach we propose is quantum-like: we use ladder and number operators to describe healthy and tumor cells birth and death, and the evolution is ruled by a non-hermitian Hamiltonian which includes, in a non reversible way, the basic biological mechanisms we consider for the system. We show that this approach is rather efficient in describing some processes of the cells. We further add some medical treatment, described by adding a suitable term in the Hamiltonian, which controls and limits the growth of tumor cells, and we propose an optimal approach to stop, and reverse, this growth.

General Physics and Astronomylcsh:AstrophysicsTumor cells01 natural sciencesArticle010305 fluids & plasmassymbols.namesakeOperatorial models; Schrödinger dynamics; non Hermitian Hamiltonian; Tumoral proliferation modelSchrödinger dynamicParticle number operatorlcsh:QB460-4660103 physical scienceslcsh:Science010306 general physicsSettore MAT/07 - Fisica MatematicaMathematical physicsPhysicsMedical treatmentOperatorial modelOther Quantitative Biology (q-bio.OT)Non hermitian HamiltonianTumoral proliferation modelQuantitative Biology - Other Quantitative Biologylcsh:QC1-999Birth–death processFOS: Biological sciencesSchrödinger dynamicsCancer cellsymbolslcsh:QOperatorial modelsHamiltonian (quantum mechanics)lcsh:PhysicsSelf-adjoint operator
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Non-equivariant cylindrical contact homology

2013

It was pointed out by Eliashberg in his ICM 2006 plenary talk that the integrable systems of rational Gromov-Witten theory very naturally appear in the rich algebraic formalism of symplectic field theory (SFT). Carefully generalizing the definition of gravitational descendants from Gromov-Witten theory to SFT, one can assign to every contact manifold a Hamiltonian system with symmetries on SFT homology and the question of its integrability arises. While we have shown how the well-known string, dilaton and divisor equations translate from Gromov-Witten theory to SFT, the next step is to show how genus-zero topological recursion translates to SFT. Compatible with the example of SFT of closed …

Geodesic010102 general mathematicsHomology (mathematics)Topology01 natural sciencesHamiltonian system0103 physical sciencesHomogeneous spaceEquivariant mapDilaton010307 mathematical physicsGeometry and Topology0101 mathematicsAlgebraic numberMathematics::Symplectic GeometrySymplectic geometryMathematicsJournal of Symplectic Geometry
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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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Post-post-Newtonian effects on a clean nearly-Newtonian binary

1983

Etude du taux de changement temporel moyen de l'energie newtonienne et du moment d'une binaire presque newtonienne, ponctuelle. On trouve qu'il faut ajouter quelques termes post-post newtoniens non seculaires aux flux radiatifs seculaires standards. Les termes post-post newtoniens tendent vers zero pour l'observateur du centre de masse newtonien dans le cas de l'energie mais pas dans le cas du moment. Du fait de la longue periode de ces termes ils sont observationnellement significatifs, c'est-a-dire qu'ils vont apparaitre comme s'ils etaient des effets seculaires

GravitationPhysicsTheoretical physicsSpace and Planetary ScienceGravitational waveBinary starNewtonian fluidBinary numberAstronomy and AstrophysicsCenter of massMathematical physicsMonthly Notices of the Royal Astronomical Society
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Relativistic simulations of rotational core collapse : II. Collapse dynamics and gravitational radiation

2002

We have performed hydrodynamic simulations of relativistic rotational supernova core collapse in axisymmetry and have computed the gravitational radiation emitted by such an event. Details of the methodology and of the numerical code have been given in an accompanying paper. We have simulated the evolution of 26 models in both Newtonian and relativistic gravity. Our simulations show that the three different types of rotational supernova core collapse and gravitational waveforms identified in previous Newtonian simulations (regular collapse, multiple bounce collapse, and rapid collapse) are also present in relativistic gravity. However, rotational core collapse with multiple bounces is only …

Gravity (chemistry)FOS: Physical sciencesCollapse (topology)General Relativity and Quantum Cosmology (gr-qc)AstrophysicsAstrophysicsUNESCO::ASTRONOMÍA Y ASTROFÍSICAGeneral Relativity and Quantum CosmologyGravitational wavesGravitationGeneral Relativity and Quantum CosmologyNewtonian fluidGravitational waves ; Hydrodynamics ; Neutron Rotation ; SupernovaePhysicsGravitational waveNeutron RotationAstrophysics (astro-ph)Astronomy and AstrophysicsMechanics:ASTRONOMÍA Y ASTROFÍSICA::Cosmología y cosmogonia [UNESCO]SupernovaAmplitudeSupernovaeSpace and Planetary ScienceHydrodynamicsUNESCO::ASTRONOMÍA Y ASTROFÍSICA::Cosmología y cosmogoniaEvent (particle physics):ASTRONOMÍA Y ASTROFÍSICA [UNESCO]
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On Grinberg’s Criterion

2019

We generalize Grinberg’s hamiltonicity criterion for planar graphs. To this end, we first prove a technical theorem for embedded graphs. As a special case of a corollary of this theorem we obtain Zaks’ extension of Grinberg’s Criterion (which encompasses earlier work of Gehner and Shimamoto), but the result also implies Grinberg’s formula in its original form in a much broader context. Further implications are a short proof for a slightly strengthened criterion of Lewis bounding the length of a shortest closed walk from below as well as a generalization of a theorem due to Bondy and Häggkvist. See full version of the article: https://www.sciencedirect.com/science/article/pii/S01956698183013…

Grinberg’s Criterion Hamiltonian cycle 2-factor spanning walks
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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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On critical behaviour in systems of Hamiltonian partial differential equations

2013

Abstract We study the critical behaviour of solutions to weakly dispersive Hamiltonian systems considered as perturbations of elliptic and hyperbolic systems of hydrodynamic type with two components. We argue that near the critical point of gradient catastrophe of the dispersionless system, the solutions to a suitable initial value problem for the perturbed equations are approximately described by particular solutions to the Painlevé-I (P $$_I$$ I ) equation or its fourth-order analogue P $$_I^2$$ I 2 . As concrete examples, we discuss nonlinear Schrödinger equations in the semiclassical limit. A numerical study of these cases provides strong evidence in support of the conjecture.

Hamiltonian PDEsFOS: Physical sciencesSemiclassical physicsPainlevé equationsArticleSchrödinger equationHamiltonian systemsymbols.namesakeMathematics - Analysis of PDEs37K05Modelling and SimulationGradient catastrophe and elliptic umbilic catastrophe34M55FOS: MathematicsInitial value problemSettore MAT/07 - Fisica MatematicaEngineering(all)Mathematical PhysicsMathematicsG100Partial differential equationConjectureNonlinear Sciences - Exactly Solvable and Integrable SystemsHyperbolic and Elliptic systemsApplied MathematicsMathematical analysisQuasi-integrable systemsGeneral EngineeringMathematical Physics (math-ph)35Q55Nonlinear systemModeling and SimulationsymbolsExactly Solvable and Integrable Systems (nlin.SI)Hamiltonian (quantum mechanics)Gradient catastrophe and elliptic umbilic catastrophe; Hamiltonian PDEs; Hyperbolic and Elliptic systems; Painlevé equations; Quasi-integrable systemsAnalysis of PDEs (math.AP)
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Inverse eigenvalue problem for normal J-hamiltonian matrices

2015

[EN] A complex square matrix A is called J-hamiltonian if AT is hermitian where J is a normal real matrix such that J(2) = -I-n. In this paper we solve the problem of finding J-hamiltonian normal solutions for the inverse eigenvalue problem. (C) 2015 Elsevier Ltd. All rights reserved.

Hamiltonian matrixApplied MathematicsHamiltonian matrixMoore–Penrose inverseMatrius (Matemàtica)Normal matrixSquare matrixHermitian matrixCombinatoricssymbols.namesakeMatrix (mathematics)Inverse eigenvalue problemsymbolsÀlgebra linealDivide-and-conquer eigenvalue algorithmMATEMATICA APLICADAHamiltonian (quantum mechanics)Normal matrixEigenvalues and eigenvectorsMathematicsMathematical physicsApplied Mathematics Letters
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