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Foundations of Physics

, Volume 23, Issue 2, pp 185–195 | Cite as

Understanding geometrical phases in quantum mechanics: An elementary example

  • J. C. Solem
  • L. C. Biedenharn
Part I. Invited Papers Dedicated To Asim Orhan Barut

Abstract

We discuss an exact solution to the simplest nontrivial example of a geometrical phase in quantum mechanics. By means of this example: (1) we elucidate the fundamental distinction between rays and vectors in describing quantum mechanical states; (2) we show that superposition of quantal states is invalid; only decomposition is allowed—which is adequate for the measurement process. Our example also shows that the origin of singularities in the analog vector potential is to be found in the unavoidable breaking of projective symmetry caused by using the Schrödinger equation.

Keywords

Exact Solution Quantum Mechanic Quantal State Mechanical State Vector Potential 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© Plenum Publishing Corporation 1993

Authors and Affiliations

  • J. C. Solem
    • 1
  • L. C. Biedenharn
    • 2
  1. 1.Theoretical DivisionLos Alamos National LaboratoryLos Alamos
  2. 2.Department of PhysicsUniversity of Texas at AustinAustin

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