Measurement in Quantum Physics: Experimental and Formal Approaches.

Ken Krechmer

In classic measurement theory each physical measurement result has a precision which becomes infinitesimal as noise and distortion approach zero, i. e., exact repetitive measurement results (± a Planck) are theoretically possible. This classic measurement theory is not well correlated with experimental measurement results. When noise and distortion are minimized, repetitive experimental measurement results always display a Gaussian distribution. This paper first addresses experimental measurements by developing a formal measurement function and related definitions. The formal measurement function identifies that an exact repetitive classic measurement result is not possible in theory as well as in experiments. This new measurement function is then shown to explain the existing quantum measurement problems.

E. C. G. Sudarshan, T. N. Sherry, S. R. Gautam

Ken Krechmer

Abstract This paper is a response to the EPR paper titled: "Can quantum-mechanical description of physical reality be considered complete?", published in Physical Review in 1935. A quantum-mechanical (QM) measure function describes a distribution of local results, while each experimental measurement process produces one result as exact as allowed by a measuring apparatus calibrated to a non-local unit standard. Repeating experimental measurements produces a Gaussian distribution of measurement results. These QM and experimental measurement result distributions can be compared. To compare a QM measure function describing a distribution of eigenvectors to a distribution of repetitive experimental measurement results, it is necessary to determine, by calibration, the precision of the eigenvectors to the same standard as the experimental results, because each eigenvector evidences uncertainty relative to a standard. When the calibration process is recognized as formal as well as empirical, QM measure function and experimental measurement process results are unified.

Hitoshi Wakita

John L. McKnight

Philip Goyal, Kevin H. Knuth, Ariel Caticha +2 more

In this paper, we explore the possibility that the concept of information may enable a derivation of the quantum formalism from a set of physically comprehensible postulates. Taking the probabilistic nature of measurements as a given, we introduce the concept of information via a novel invariance principle, the Principle of Information Gain. Using this principle, we then show that it is possible to deduce the abstract quantum formalism for finite‐dimensional quantum systems from a set of postulates, of which one is a novel physical assumption, and the remainder are based on experimental facts characteristic of quantum phenomena or are drawn from classical physics. The concept of information plays a key role in the derivation, and gives rise to some of the central structural features of the quantum formalism.