منابع مشابه
Adiabatic Product Expansion
The time-evolution operator for an explicitly time-dependent Hamiltonian is expressed as the product of a sequence of unitary operators. These are obtained by successive time-dependent unitary transformations of the Hilbert space followed by the adiabatic approximation at each step. The resulting adiabatic product expansion yields a generalization of the quantum adiabatic approximation. Further...
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We outline a method based on successive canonical transformations which yields a product expansion for the evolution operator of a general (possibly non-Hermitian) Hamiltonian. For a class of such Hamiltonians this expansion involves a finite number of terms, and our method gives the exact solution of the corresponding timedependent Schrödinger equation. We apply this method to study the dynami...
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We begin by allowing a gas to occupy a well insulated vessel, where the pressure (Pinitial) is a bit higher than atmospheric pressure (Vinitial and Tinitial are known). The vessel is then opened and closed rapidly, allowing the gas to escape at an intermediate pressure equal to atmospheric pressure (Pinter). The speed with which this is done is crucial, because if there is appreciable heat loss...
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ژورنال
عنوان ژورنال: Physics Letters A
سال: 1997
ISSN: 0375-9601
DOI: 10.1016/s0375-9601(97)00100-x