An abstract stationary approach to perturbation of continuous spectra and scattering theory
An abstract stationary approach to perturbation of continuous spectra and scattering theory
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连续光谱扰动的抽象平稳方法和散射理论
DOI:
10.1007/bf02786670
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发表时间:
1967
期刊:
影响因子:
--
通讯作者:
S. Kuroda
中科院分区:
文献类型:
--
作者:
S. Kuroda
The main purpose of the present paper is to develop a new approach to the theory of perturbation of continuous spectra and scattering. Specifically, it is shown that several problems which have been treated separately by different methods can be handled systematically by one and the same approach. As one of the necessary tools we also formulate a spectral representation theorem for a self-adjoint operator in a separable Hilbert space. This gives seemingly a new kind of representation of such an operator by a multiplicative operator in a certain space of vector valued functions. Most of the results of the present paper was announced in a rough form in an expository article of the writer [16], which also contains an explanation of the background and a heuristic account of our approach. Thus, the present paper is devoted exclusively to a general formulation and a detailed proof. The methods of recent investigation in this field may be classified, roughly speaking, into two types. The first one, the stationary method, has been most effective in the problems of smooth perturbation. Here," smooth perturbation" is used in a vague sense and what is meant by it is gentle perturbation of Friedrichs [9] and Rejto [18], a work of Ikebe [10] on Schr6dinger operators, a work of Faddeev [8] on the Friedrichs' model, and so on. In this method a problem is usually solved in a certain spectral representation space suitably chosen in each individual case. On the contrary, in the problems of perturbation with a trace condition the second method, the time-dependent one, has been