Communications in Mathematical Physics

, Volume 84, Issue 3, pp 403–438

The rotation number for almost periodic potentials

  • R. Johnson
  • J. Moser


We define and analyze the rotation number for the almost periodic Schrödinger operatorL= −d2/dx2+q(x). We use the rotation number to discuss (i) the spectrum ofL; (ii) its relation to the Korteweg-de Vries equation.


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Copyright information

© Springer-Verlag 1982

Authors and Affiliations

  • R. Johnson
    • 1
  • J. Moser
    • 2
  1. 1.Department of MathematicsUniversity of Southern CaliforniaLos AngelesUSA
  2. 2.ETH-ZentrumZürichSwitzerland

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