Volume 17: Pages 80-94, 2004

Internal Measurement: Some Aspects of Quantum Theory in Biology

András Balázs

Department of Biological Physics, Eötvös Lóránd University, Pázmány sétány 1., H‐1117 Budapest, Hungary

The unconventional current notion of “internal measurement” in biological systems is approached in both a conceptual and a historical way. The historical survey emphasizes fundamental questions, presented in a nontechnical language, from the early suggestions of Bohr, continued by Jordan and Elsasser, first of all of the generalized complementarity principle, stating, en gross, the complementarity of structural details and biological functions. It is suggested, by and large, that the full content of this line of thought is brought out only by present‐day schemes of “internal measurement,” which are discussed in some detail. In fact, it is pointed out that theoretical and experimental arguments go hand in hand in such difficult conceptual problems, and this also marks the history of the theoretical simultaneous account of (internalized) measurement (also termed informational, symbolic, semiotic, etc., internal control), amounting to the “automata theoretical” side and the quantum‐dynamical side. Thus it is our standpoint that the “classical” (in fact quasi‐classical) behavior of biological internal dynamics is closely related to the internal, measurementally constrained, biomolecular interactions. An independent implementation of the present author's approach to an affine Hilbert spaces concept is introduced that is built upon the notion of an endogenous “time‐inversion symmetry‐breaking/restoring” mechanism, particular to his own concept of the general view of “internal symmetry breaking.”

Keywords: quantum biophysics, internalist stance, internal measurement, history, current theories of internal measurement

Received: October 9, 2003; Published online: December 15, 2008