## Abstract We describe the essential spectrum of a hypoelliptic pseudoβdifferential operator which is the sum of a constantcoefficients operator and an operator with coefficients vanishing at infinity. (Β© 2007 WILEYβVCH Verlag GmbH & Co. KGaA, Weinheim)
Gaps in the essential spectrum of pseudo differential operators
β Scribed by M.W Wong
- Publisher
- Elsevier Science
- Year
- 1981
- Tongue
- English
- Weight
- 544 KB
- Volume
- 83
- Category
- Article
- ISSN
- 0022-247X
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