Hypoelliptic systems of complex vector fields
نویسندگان
چکیده
منابع مشابه
Some Non-analytic-hypoelliptic Sums of Squares of Vector Fields
Certain second-order partial differential operators, which are expressed as sums of squares of real-analytic vector fields in R3 and which are well known to be C hypoelliptic, fail to be analytic hypoelliptic.
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15 صفحه اولIntegration of Complex Vector Fields
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Let {Zj} be a finite collection of vector fields, with smooth complex-valued coefficients, defined in an open subset U of Euclidean space. Let Z∗ j be the formal adjoint of Zj , with respect to the Hilbert space structure L2 associated to some measure with a smooth nonvanishing density. Consider the operator L = ∑ j Z ∗ jZj, which we shall refer to as a sum of squares. L is said to be hypoellip...
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ژورنال
عنوان ژورنال: Banach Center Publications
سال: 1992
ISSN: 0137-6934,1730-6299
DOI: 10.4064/-27-2-323-326