Lot 87
  • 87

FEYNMAN, RICHARD P. AM ON STRUCTURE OF HYDROGEN VIA DIRAC, SCHRÖDINGER, & KLEIN-GORDON, 1969

Estimate
30,000 - 50,000 USD
Log in to view results
bidding is closed

Description

  • "Dirac Equ.[ation] H atom... Schrodinger... Klein Gordon...", 26 February, 1969.
Autograph manuscript, 4 pp (8 1/2 x 11 in), in pencil on plain white paper, 26 February, 1969.

Catalogue Note

FEYNMAN EXAMINES THE RELATIVISTIC FINE STRUCTURE OF HYDROGEN VIA THE DIRAC, SCHRÖDINGER, AND KLEIN-GORDON EQUATIONS. Written while at Caltech, in February of 1969, the present manuscripts are possibly notes for a graduate course in quantum physics, parsing the differences in these canonical quantum equations, explicitly solving them in the context of the H-atom. Next to the solution for the Dirac equation, he notes:

"WOW. NO EXPLICIT ɣ DEPENDENCE! LOOKS LIKE SCHROD[INGER]....". Under the Schrödinger section he points out "Exactly like Dirac, except for sign...", and in the Klein Gordon section, he notes "Same as Schrödinger, except..."

Among the most significant manuscript lots in this Sale, the trifecta of Dirac, Schrödinger, & Klein-Gordon illustrates Feynman’s craft, deft hand and creative pedagogy at its finest hour.

Paul Dirac, who shared the 1933 Nobel Prize in Physics with Schrödinger, was Feynman’s greatest hero and had thoroughly captured the imagination of the young MIT undergraduate, who had purchased Dirac’s classic, The Principles of Quantum Mechanics as a teenager, but found it nearly impenetrable, though a tremendous inspiration (see lot 100). The intellectual legacy of this early inspiration was Feynman’s QED Nobel Prize itself; Dirac deserves full credit for that. Nevertheless, the Klein-Gordon equation also figures quite prominently in the folklore of Feynman, who had dueled with MIT classmate Ted Welton on the matter of this field-theoretic alternative to the Dirac equation during their wunderkind Knabenphysik (“Boy Physics”) days of Summer 1936 (Gleick, p. 74).

 The derivations presented, which tease out intricate details of the relativistic fine-structure in the H-atom (so-called “spin-coupling” interaction) have antecedents in the early work of Bohr & Sommerfeld on precessing elliptical orbitals, but are remarkable here for their particular Feynmanesque resonance. It must have been with great satisfaction, post-Nobel and 30 years past his MIT graduation, that Feynman returned to these particular calculations with his students.