Schwinger's Quantum Action Principle

From Dirac’s Formulation Through Feynman’s Path Integrals, the Schwinger-Keldysh Method, Quantum Field Theory, to Source Theory

  • Kimball A. Milton

Part of the SpringerBriefs in Physics book series (SpringerBriefs in Physics)

Table of contents

  1. Front Matter
    Pages i-viii
  2. Kimball A. Milton
    Pages 1-2
  3. Kimball A. Milton
    Pages 3-14
  4. Kimball A. Milton
    Pages 15-29
  5. Kimball A. Milton
    Pages 31-50
  6. Kimball A. Milton
    Pages 51-61
  7. Kimball A. Milton
    Pages 63-90
  8. Kimball A. Milton
    Pages 91-112
  9. Kimball A. Milton
    Pages 113-114
  10. Back Matter
    Pages 115-116

About this book


Starting from the earlier notions of stationary action principles, these tutorial notes shows how Schwinger’s Quantum Action Principle descended from Dirac’s formulation, which independently led Feynman to his path-integral formulation of quantum mechanics. Part I brings out in more detail the connection between the two formulations, and applications are discussed. Then, the Keldysh-Schwinger time-cycle method of extracting matrix elements is described. Part II will discuss the variational formulation of quantum electrodynamics and the development of source theory.


Julian Schwinger Principle of Least Action in Quantum Mechanics Quantum Action Principle Schwinger-Keldysh Formulation Source Theory Variational Formulation of Quantum Mechanics

Authors and affiliations

  • Kimball A. Milton
    • 1
  1. 1.Homer L. Dodge Department of Physics and AstronomyThe University of OklahomaNormanUSA

Bibliographic information

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