## 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)
On the essential spectrum of an arbitrary operator. I
β Scribed by Martin Schechter
- Publisher
- Elsevier Science
- Year
- 1966
- Tongue
- English
- Weight
- 551 KB
- Volume
- 13
- Category
- Article
- ISSN
- 0022-247X
No coin nor oath required. For personal study only.
π SIMILAR VOLUMES
## Abstract Descloux and Geymonat considered a model problem for a plasma in a toroidal configuration and conjectured that the essential spectrum has an explicitly given band structure. This conjecture was recently proved by Faierman, Mennicken, and MΓΆller by employing an operator matrix representa
Abrtract. Sufficient conditions are given such that the product T1T2 of two unbounded operators in Hilbert spaces is essentially selfadjoint and that the nonzero numbers in the essential spectrum of the closure of TlT2 coincide with the nonzero numbers in the essential spectrum of T2T1. If the essen