Quantum Information Processing, Vol. 5, No. 4, August 2006 (© 2006)
What Are Quantum States?
Received November 15, 2005; accepted December 29, 2005; Published online April 28, 2006
We present three strong arguments against the ontic interpretation of quantum
states. We then show that the appropriate alternative is not an epistemic interpre-
tation, but viewing quantum states as representing the available knowledge about
the potentialities of a quantum system from the perspective a of a particular point
in space. Unlike ordinary knowledge, which requires a knower, available knowledge
can be assumed to be present regardless of a knower. The relationship between
“perspectives on potentialities” and “the potentialities themselves” is clariﬁed.
KEY WORDS: Process philosophy; Whitehead’s philosophy; quantum physics.
PAC S : 01.70.+w; 03.65.-w; 03.65Ud.
1. ARGUMENTS AGAINST THE ONTIC INTERPRETATION
OF QUANTUM STATES
Let us begin with the Fifth Solvey Conference (1927). The Conference is
famous for what happened outside the public lectures: The Einstein chal-
lenges to the Uncertainty Principle and Bohr’s rebuttals. In one of the
public sessions, however, Einstein pointed out that the collapse, which he
assumed took place on a t = const. hypersurface, means that the inﬂuence
of the appearance of an elementary quantum events leads to an instan-
taneous (faster than light) propagation of the change in the value of the
wave function everywhere on the hypersurface. Einstein tacitly assumed the
ontic interpretation of the wave function.
As on many other occasions, although Einstein began saying “I
must apologize for not having penetrating quantum mechanics deeply
his point was penetrating enough to generate, decades later, a
strong objection to the ontic interpretation.
Department of Physics and Astronomy, Colgate University, Hamilton, New York 13346,
USA. E-mail: firstname.lastname@example.org
1570-0755/06/0800-0233/0 © 2006 Springer Science+Business Media, Inc.