Search results for "Compact form"

showing 3 items of 3 documents

Slow-roll corrections in multi-field inflation: a separate universes approach

2018

In view of cosmological parameters being measured to ever higher precision, theoretical predictions must also be computed to an equally high level of precision. In this work we investigate the impact on such predictions of relaxing some of the simplifying assumptions often used in these computations. In particular, we investigate the importance of slow-roll corrections in the computation of multi-field inflation observables, such as the amplitude of the scalar spectrum $P_\zeta$, its spectral tilt $n_s$, the tensor-to-scalar ratio $r$ and the non-Gaussianity parameter $f_{NL}$. To this end we use the separate universes approach and $\delta N$ formalism, which allows us to consider slow-roll…

DYNAMICSCosmology and Nongalactic Astrophysics (astro-ph.CO)ComputationFOS: Physical sciencesCMB01 natural sciences114 Physical sciences0103 physical sciencesStatistical physicsinflationMULTICOMPONENT INFLATON010303 astronomy & astrophysicsPhysicsSPECTRUMSlow roll010308 nuclear & particles physicsEquations of motionCONSTRAINTSAstronomy and AstrophysicsObservableCOSMOLOGICAL PERTURBATIONSEXPANSION115 Astronomy Space scienceAmplitudeHypersurfacecosmological perturbation theoryCompact formMulti field2ND-ORDERAPPROXIMATIONGENERATIONAstrophysics - Cosmology and Nongalactic Astrophysics
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WEAK TRANSITION FORM FACTORS IN RARE HEAVY MESON DECAYS

1991

The transition form factors required for the rare heavy meson decays are evaluated. The model-independent absolutely normalized form factors, written in a compact form, among heavy to light and heavy to heavy meson transitions in the states such as 0−+→0−+, 1−, 0++, 1++ are given. A set of general relations among the form factors is obtained. The form factors involved in the rare B-meson decays are given as a direct application.

PhysicsNuclear and High Energy PhysicsParticle physicsParticle propertiesMesonHadronGeneral Physics and AstronomyAstronomy and AstrophysicsElementary particleNuclear physicsParticle decayCompact formB mesonBosonModern Physics Letters A
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Solution of the Lindblad equation in Kraus representation

2006

The so-called Lindblad equation, a typical master equation describing the dissipative quantum dynamics, is shown to be solvable for finite-level systems in a compact form without resort to writing it down as a set of equations among matrix elements. The solution is then naturally given in an operator form, known as the Kraus representation. Following a few simple examples, the general applicability of the method is clarified.

PhysicsQuantum PhysicsSettore FIS/02 - Fisica Teorica Modelli E Metodi MatematiciLindblad equationFOS: Physical sciencesAtomic and Molecular Physics and OpticsSettore FIS/03 - Fisica Della MateriaThe so-called Lindblad equation a typical master equation describing the dissipative quantum dynamics is shown to be solvable for finite-level systems in a compact form without resort to writing it down as a set of equations among matrix elements. The solution is then naturally given in an operator form known as the Kraus representation. Following a few simple examples the general applicability of the method is clarified.Open quantum systemQuantum processMaster equationDissipative systemQuantum operationMethod of quantum characteristicsQuantum Physics (quant-ph)Quantum statistical mechanicsMathematical physics
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