Perturbation Growth and Structure in Time-Dependent Flows
نویسندگان
چکیده
منابع مشابه
Perturbation Growth and Structure in Time-Dependent Flows
Asymptotic linear stability of time-dependent flows is examined by extending to nonautonomous systems methods of nonnormal analysis that were recently developed for studying the stability of autonomous systems. In the case of either an autonomous or a nonautonomous operator, singular value decomposition (SVD) analysis of the propagator leads to identification of a complete set of optimal pertur...
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Perturbation growth in uncertain systems is examined and related to previous work in which linear stability concepts were generalized from a perspective based on the nonnormality of the underlying linear operator. In this previous work the linear operator, subject to an initial perturbation or a stochastic forcing distributed in time, was either fixed or time varying, but in either case the ope...
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Our starting point is the set of eigenstates n of the unperturbed Hamiltonian 0 n H n E n = , notice we are not labeling with a zero, no 0 n E , because with a time-dependent Hamiltonian, energy will not be conserved, so it is pointless to look for energy corrections. What happens instead, provided the perturbation is not too large, is that the system makes transitions between the eigenstates n...
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We describe radiative processes in Quantum Cosmology, from the solutions of the Wheeler De Witt equation. By virtue of this constraint equation, the quantum propagation of gravity is modified by the matter interaction hamiltonian at the level of amplitudes. In this we generalize previous works where gravity was coupled only to expectation values of matter operators. By a “reduction formula” we ...
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ژورنال
عنوان ژورنال: Journal of the Atmospheric Sciences
سال: 1999
ISSN: 0022-4928,1520-0469
DOI: 10.1175/1520-0469(1999)056<3622:pgasit>2.0.co;2