The effectively hyperbolic Cauchy problem
The effectively hyperbolic Cauchy problem
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有效双曲柯西问题
DOI:
10.1007/bfb0090884
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发表时间:
1991
期刊:
影响因子:
--
通讯作者:
T. Nishitani
中科院分区:
文献类型:
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作者:
T. Nishitani
We introduce the notion of effectively hyperbolic operators following Ivrii-Petkov [11] and Hormander [9J. We also give a geometric characterization of it, following Nishitani [29, 31J: the propagation cone of the localization of the principal symbol is transversal to the doubly characteristic set (Lemma 1.2. 1). This characterization provides a generalization of this notion (Lemma 1.1. 3). We rewrite this condition in terms of time functions. Indeed, the effective hyperbolicity requires the existence of a special time function vanishing on the double characteristic set and vice versa (Lemmas 1.2. 2 and 1.2. 3).