Quantum mechanics, Furry's hypothesis and a measure of decoherence in the K^0 \bar{K}^0 system

TL;DR

This paper investigates how spontaneous decoherence affects strangeness correlations in entangled K^0 ar{K}^0 pairs, emphasizing the basis dependence of decoherence measures and estimating the decoherence parameter from experimental data.

Contribution

It introduces a basis-dependent parameterization of decoherence in K^0 ar{K}^0 systems and analyzes its implications using recent experimental data.

Findings

Decoherence parameter  estimated for different bases.

Decoherence measure depends on the chosen basis.

Experimental data constrains the degree of spontaneous decoherence.

Abstract

We consider strangeness correlations of the EPR type in K^0 \bar{K}^0 pairs created in a J^{PC} = 1^{--} state as a function of time under the hypothesis that spontaneous decoherence takes place. We parameterize the degree of decoherence by a factor (1-\zeta) which multiplies the quantum-mechanical interference terms occurring in the amplitudes for like and unlike strangeness events and discuss the dependence of this procedure on the basis chosen in the K^0--\bar{K}^0 space to which the interference terms correspond. Consequently, all statements about the ``decoherence parameter'' \zeta inferred from experimental data are basis-dependent as well. We illustrate this point by estimating the value of \zeta for the two bases {K_L, K_S} and {K^0, \bar{K}^0} with the help of recent data of the CPLEAR experiment.