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Solvability and complex limit bicharacteristics

Dencker, Nils LU (2020) In Operator Theory: Advances and Applications 276. p.247-276
Abstract

We shall study the solvability of pseudodifferential operators which are not of principal type. The operator will have complex principal symbol satisfying condition (Ψ) and we shall consider the limits of semibicharacteristics at the set where the principal symbol vanishes of at least second order. The convergence shall be as smooth curves, and we shall assume that the normalized complex Hamilton vector field of the principal symbol over the semicharacteristics converges to a real vector field. Also, we shall assume that the linearization of the real part of the normalized Hamilton vector field at the semibicharacteristic is tangent to and bounded on the tangent space of a Lagrangean submanifold at the semibicharacteristics, which we... (More)

We shall study the solvability of pseudodifferential operators which are not of principal type. The operator will have complex principal symbol satisfying condition (Ψ) and we shall consider the limits of semibicharacteristics at the set where the principal symbol vanishes of at least second order. The convergence shall be as smooth curves, and we shall assume that the normalized complex Hamilton vector field of the principal symbol over the semicharacteristics converges to a real vector field. Also, we shall assume that the linearization of the real part of the normalized Hamilton vector field at the semibicharacteristic is tangent to and bounded on the tangent space of a Lagrangean submanifold at the semibicharacteristics, which we call a grazing Lagrangean space. Under these conditions one can invariantly define the imaginary part of the subprincipal symbol. If the quotient of the imaginary part of the subprincipal symbol with the norm of the Hamilton vector field switches sign from − to + on the bicharacteristics and becomes unbounded as they converge to the limit, then the operator is not solvable at the limit bicharacteristic.

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Please use this url to cite or link to this publication:
author
organization
publishing date
type
Chapter in Book/Report/Conference proceeding
publication status
published
subject
host publication
Operator Theory : Advances and Applications - Advances and Applications
series title
Operator Theory: Advances and Applications
volume
276
pages
30 pages
publisher
Springer Gabler
external identifiers
  • scopus:85088574486
ISSN
2296-4878
0255-0156
DOI
10.1007/978-3-030-31531-3_16
language
English
LU publication?
yes
id
08cb567c-b80a-4c77-9a81-146d00b310a2
date added to LUP
2020-08-05 11:34:24
date last changed
2024-04-03 13:08:16
@inbook{08cb567c-b80a-4c77-9a81-146d00b310a2,
  abstract     = {{<p>We shall study the solvability of pseudodifferential operators which are not of principal type. The operator will have complex principal symbol satisfying condition (Ψ) and we shall consider the limits of semibicharacteristics at the set where the principal symbol vanishes of at least second order. The convergence shall be as smooth curves, and we shall assume that the normalized complex Hamilton vector field of the principal symbol over the semicharacteristics converges to a real vector field. Also, we shall assume that the linearization of the real part of the normalized Hamilton vector field at the semibicharacteristic is tangent to and bounded on the tangent space of a Lagrangean submanifold at the semibicharacteristics, which we call a grazing Lagrangean space. Under these conditions one can invariantly define the imaginary part of the subprincipal symbol. If the quotient of the imaginary part of the subprincipal symbol with the norm of the Hamilton vector field switches sign from − to + on the bicharacteristics and becomes unbounded as they converge to the limit, then the operator is not solvable at the limit bicharacteristic.</p>}},
  author       = {{Dencker, Nils}},
  booktitle    = {{Operator Theory : Advances and Applications}},
  issn         = {{2296-4878}},
  language     = {{eng}},
  pages        = {{247--276}},
  publisher    = {{Springer Gabler}},
  series       = {{Operator Theory: Advances and Applications}},
  title        = {{Solvability and complex limit bicharacteristics}},
  url          = {{http://dx.doi.org/10.1007/978-3-030-31531-3_16}},
  doi          = {{10.1007/978-3-030-31531-3_16}},
  volume       = {{276}},
  year         = {{2020}},
}