Search results for "expansions"

showing 10 items of 21 documents

Vanishing chiral couplings in the large-Nc resonance theory

2007

5 pages, 2 figures.-- PACS nrs.: 12.39.Fe; 11.15.Pg; 12.38.-t.-- ISI Article Identifier: 000247625300022.-- ArXiv pre-print available at: http://arxiv.org/abs/hep-ph/0611375

Quantum chromodynamicsPhysicsNuclear and High Energy PhysicsParticle physicsChiral perturbation theory[PACS] Chiral Lagrangians in quark modelsHigh Energy Physics::LatticeHigh Energy Physics::PhenomenologyForm factor (quantum field theory)FOS: Physical sciencesPerturbation theoryResonance (particle physics)Low-energy constantsHigh Energy Physics - Phenomenologysymbols.namesake[PACS] Expansions for large numbers of components (e.g. 1/Nc expansions) in gauge theoriesHigh Energy Physics - Phenomenology (hep-ph)Quantum Chromodynamics (QCD)Resonance theorysymbolsPerturbation theoryChirality (chemistry)Lagrangian
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Jerarquies de models sigma: aplicacions a teories de Supergravetat i a teories conformes

2012

207 páginas. Tesis Doctoral del Departamento de Física Teórica, de la Universidad de Valencia. Fecha de lectura: 5 octubre 2012.

S-expansionscoset spacesquantum groupsUNESCO::FÍSICA::Física Teórica:MATEMÁTICAS::Álgebra::Grupos generalidades [UNESCO]UNESCO::MATEMÁTICAS::Álgebra::Grupos generalidades:FÍSICA::Física Teórica [UNESCO]quantum groups; coset spaces; semigroups; S-expansionssemigroups
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MR3586679 Reviewed Maksimović, Snježana(BS-BALUEL); Mincheva-Kamińska, Svetlana(PL-RZSZM); Pilipović, Stevan(SE-NOVIS-NDM); Sokoloski, Petar(MK-SKOPN…

2017

The purpose of the paper is to investigate ultradistributions of both Beurling and Roumieu (briefly, B and R) types with the help of a sequential approach, considering certain equivalence classes of fundamental sequences of smooth functions defined by ultradifferential operators. More precisely, the authors define as s-ultradistributions the equivalence classes U(t) and U{t} of B and R types respectively on test functions belonging respectively to D′(t)(Ω) and D′{t}(Ω) on the open set Ω⊂Rn, and T(t), T{t}, T~(t) and T~{t} of (tempered) t- and t~-distributions, and study their properties. Finally, the authors prove the existence of topological isomorphism between the classes T(t), T{t}, T~(t…

Settore MAT/05 - Analisi Matematicafundamental sequences Hermite expansions
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Stationary and non-stationary probability density function for non-linear oscillators

1997

A method for the evaluation of the stationary and non-stationary probability density function of non-linear oscillators subjected to random input is presented. The method requires the approximation of the probability density function of the response in terms of C-type Gram-Charlier series expansion. By applying the weighted residual method, the Fokker-Planck equation is reduced to a system of non-linear first order ordinary differential equations, where the unknowns are the coefficients of the series expansion. Furthermore, the relationships between the A-type and C-type Gram-Charlier series coefficient are derived.

Stationary distributionCharacteristic function (probability theory)Applied MathematicsMechanical EngineeringMathematical analysisProbability density functionStationary sequencestochastic non-linear dynamics; Gram-Charlier expansions; approximate probability density functionGram-Charlier expansionsMechanics of Materialsstochastic non-linear dynamicsProbability distributionProbability-generating functionapproximate probability density functionSeries expansionRandom variableMathematics
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Fractional calculus approach to the statistical characterization of random variables and vectors

2009

Fractional moments have been investigated by many authors to represent the density of univariate and bivariate random variables in different contexts. Fractional moments are indeed important when the density of the random variable has inverse power-law tails and, consequently, it lacks integer order moments. In this paper, starting from the Mellin transform of the characteristic function and by fractional calculus method we present a new perspective on the statistics of random variables. Introducing the class of complex moments, that include both integer and fractional moments, we show that every random variable can be represented within this approach, even if its integer moments diverge. A…

Statistics and ProbabilityMellin transformStatistical Mechanics (cond-mat.stat-mech)Characteristic function (probability theory)Multivariate distributionMultivariate random variableMathematical analysisFOS: Physical sciencesMoment-generating functionCondensed Matter PhysicsFractional calculusFractional and complex moments; Multivariate distributions; Power-law tails; Inverse Mellin transformFractional and complex momentIngenieurwissenschaftenApplied mathematicsddc:620Inverse Mellin transformSettore ICAR/08 - Scienza Delle CostruzioniRandom variableCondensed Matter - Statistical MechanicsMathematicsInteger (computer science)Taylor expansions for the moments of functions of random variablesPower-law tail
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Newton algorithm for Hamiltonian characterization in quantum control

2014

We propose a Newton algorithm to characterize the Hamiltonian of a quantum system interacting with a given laser field. The algorithm is based on the assumption that the evolution operator of the system is perfectly known at a fixed time. The computational scheme uses the Crank-Nicholson approximation to explicitly determine the derivatives of the propagator with respect to the Hamiltonians of the system. In order to globalize this algorithm, we use a continuation method that improves its convergence properties. This technique is applied to a two-level quantum system and to a molecular one with a double-well potential. The numerical tests show that accurate estimates of the unknown paramete…

Statistics and Probability[ MATH.MATH-OC ] Mathematics [math]/Optimization and Control [math.OC][ PHYS.QPHY ] Physics [physics]/Quantum Physics [quant-ph]Non uniquenessFOS: Physical sciencesGeneral Physics and AstronomyQuantum controlsymbols.namesake[PHYS.QPHY]Physics [physics]/Quantum Physics [quant-ph]Fixed time[ CHIM.OTHE ] Chemical Sciences/OtherQuantum systemNumerical testsMathematical PhysicsMathematicsQuantum PhysicsPropagatorStatistical and Nonlinear PhysicsNMRContinuation methodModeling and Simulationsymbolsinverse problemidentification02.30.Yy Control theory02.30.Tb Operator theory42.50.Ct Quantum description of interaction of light and matter; related experiments02.60.Cb Numerical simulation; solution of equations03.65.Ge Solutions of wave equations: bound states02.30.Mv Approximations and expansions[MATH.MATH-OC]Mathematics [math]/Optimization and Control [math.OC]Quantum Physics (quant-ph)Hamiltonian (quantum mechanics)[CHIM.OTHE]Chemical Sciences/OtherAlgorithmcontrol
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Chiral Low-Energy Constants: Status and Prospects

2007

7 pages.-- PACS nrs.: 11.15.Pg, 12.38.-t, 12.39.Fe.-- ISI Article Identifier: 000252187200017.-- ArXiv pre-print available at: http://arxiv.org/abs/0710.4405

UNESCO::FÍSICA::Física molecular[PACS] Chiral LagrangiansHigh Energy Physics::LatticeHigh Energy Physics::PhenomenologyUNESCO::FÍSICAHadronicFOS: Physical sciencesPerturbation theoryChiral LagrangianQCDLEC'sHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph):FÍSICA [UNESCO]:FÍSICA::Física molecular [UNESCO]Resonance region[PACS] Quantum chromodynamics (QCD)Chiral Lagrangian; LEC's ; Prediction ; Hadronic ; QCDPrediction[PACS] Expansions for large numbers of components (e.g. 1/Nc expansions)
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Unfolding of saddle-nodes and their Dulac time

2016

Altres ajuts: UNAB10-4E-378, co-funded by ERDF "A way to build Europe" and by the French ANR-11-BS01-0009 STAAVF. In this paper we study unfoldings of saddle-nodes and their Dulac time. By unfolding a saddle-node, saddles and nodes appear. In the first result (Theorem A) we give a uniform asymptotic expansion of the trajectories arriving at the node. Uniformity is with respect to all parameters including the unfolding parameter bringing the node to a saddle-node and a parameter belonging to a space of functions. In the second part, we apply this first result for proving a regularity result (Theorem B) on the Dulac time (time of Dulac map) of an unfolding of a saddle-node. This result is a b…

[ MATH.MATH-DS ] Mathematics [math]/Dynamical Systems [math.DS][MATH.MATH-DS]Mathematics [math]/Dynamical Systems [math.DS]Block (permutation group theory)Dynamical Systems (math.DS)Space (mathematics)01 natural sciencesCombinatoricsQuadratic equationFOS: MathematicsMathematics - Dynamical Systems0101 mathematicsBifurcationSaddleMathematicsPeriod functionApplied MathematicsUnfolding of a saddle-node010102 general mathematics16. Peace & justice010101 applied mathematicsMSC: 34C07Asymptotic expansions34C07Node (circuits)Asymptotic expansionAnalysis
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Preclinical characterization of antagomiR-218 as a potential treatment for myotonic dystrophy

2021

Myotonic dystrophy type 1 (DM1) is a rare neuromuscular disease caused by expansion of unstable CTG repeats in a non-coding region of the DMPK gene. CUG expansions in mutant DMPK transcripts sequester MBNL1 proteins in ribonuclear foci. Depletion of this protein is a primary contributor to disease symptoms such as muscle weakness and atrophy and myotonia, yet upregulation of endogenous MBNL1 levels may compensate for this sequestration. Having previously demonstrated that antisense oligonucleotides against miR-218 boost MBNL1 expression and rescue phenotypes in disease models, here we provide preclinical characterization of an antagomiR-218 molecule using the HSALR mouse model and patient-d…

antisense oligonucleotidetissue distributionRM1-950BiologyMyotonic dystrophyTranscriptomechemistry.chemical_compoundalternative splicingtranscriptomicsAtrophyDrug DiscoverymicroRNAmedicineMBNL1AntagomirCTG repeat expansionstherapeutic gene modulationCTG repeat expansions MBNL1 protein alternative splicing antisense oligonucleotide microRNAs myotonic dystrophy therapeutic gene modulation tissue distribution transcriptomicsmyotonic dystrophyMyogenesisMyotoniamedicine.diseasemicroRNAschemistryCancer researchMolecular MedicineOriginal ArticleTherapeutics. PharmacologyMBNL1 protein
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Asymptotic expansions and causal representations through the loop-tree duality

2022

Large-scale particle physics experiments have provided a vast amount of high-quality data during the last decades. A leading role has been played by the Large Hadron Collider where the evaluation and analysis of its second run is currently still in progress while the third run is about to start, promising ever higher precision data of particle collisions and subsequent decays. The agreement between experimental observations and theoretical predictions using the Standard Model of Particle Physics is excellent. Indeed, this is a problem since there are currently few clues for how genuine shortcomings of the model can be overcome. New physics phenomena can appear either at higher energies, whi…

loop-tree duality:FÍSICA [UNESCO]UNESCO::FÍSICAasymptotic expansionsquantum field theory
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