## Über quantentheoretische Umdeutung kinematischer und mechanischer Beziehungen [On the quantum-theoretical reinterpretation of kinematical and mechanical relationships]

*"The present paper seeks to establish a basis for theoretical quantum mechanics founded exclusively upon relationships between quantities which in principle are observable."*

FIRST EDITION IN ORIGINAL WRAPPERS of Heisenberg's critically important paper marking the foundation of quantum mechanics; Heisenberg was awarded the 1932 Nobel prize in physics "for the creation of quantum mechanics."

"In June 1925, while recuperating from an attack of hay fever on Helgoland, an island in the North Sea, Heisenberg solved a major physical problem—how to account for the stationary (discrete) energy states of an anharmonic oscillator. His solution, because it was analogous to that of a simple planetary atom, launched the program for the development of the quantum mechanics of atomic systems... Heisenberg published his results some months later in the Zeitschrift für Physik under the title “Über quantentheoretische Umdeutung kinematischer und mechanischer Beziehungen" ["On the quantum-theoretical reinterpretation of kinematical and mechanical relationships"]. In this article he proposed a reinterpretation of the basic concepts of mechanics.

"Heisenberg's treatment of the problem departed from Bohr's as much as Bohr's had from 19th-century tenets. Heisenberg was willing to sacrifice the idea of discrete particles moving in prescribed paths (neither particles nor paths could be observed) in exchange for a theory that would deal directly with experimental facts and lead to the quantum conditions as consequences of the theory rather than ad hoc stipulations. Physical variables were to be represented by arrays of numbers; under the influence of Einstein's paper on relativity (1905), he took the variables to represent not hidden, inaccessible structures but 'observable' (i.e., measurable) quantities" (*Britannica*).

"Heisenberg's name will always be associated with his theory of quantum mechanics, published in 1925, when he was only 23 years old. For this theory and the applications of it which resulted especially in the discovery of allotropic forms of hydrogen, Heisenberg was awarded the Nobel Prize for Physics for 1932. His new theory was based only on what can be observed, that is to say, on the radiation emitted by the atom. We cannot, he said, always assign to an electron a position in space at a given time, nor follow it in its orbit, so that we cannot assume that the planetary orbits postulated by Niels Bohr actually exist. Mechanical quantities, such as position, velocity, etc. should be represented, not by ordinary numbers, but by abstract mathematical structures called 'matrices' and he formulated his new theory in terms of matrix equations." (*Nobel Lectures, Physics 1922-41*).

Heisenberg's landmark paper inspired his colleagues Max Born and Pasqual Jordan to develop the rigorous matrix formalism necessary to mathematically complete Heisenberg's model, publishing a joint paper later in 1925 (exploring systems with one degree of freedom) and, with Heisenberg, a subsequent paper in 1926 (concerning systems with multiple degrees of freedom).

*Particle Physics, One Hundred Years of Discovery*, 43: "Foundation of quantum mechanics, Heisenberg approach. Nobel prize to W. Heisenberg awarded in 1932 'for the creation of quantum mechanics.'" ).

In: Zeitschrift für Physik, Vol. 33. Berlin: Julius Springer, 1925. Octavo, original wrappers. Light soiling to wrappers, a little wear to spine ends. Faint pencil notation at top of front wrapper; "Printed in Germany" stamps on rear wrapper.

The foundational document for quantum mechanics, rare in original wrappers and without any institutional stamps.

**Price: **
$16,000
.