On Jastrow wavefunctions containing attractive correlations

A quantum mechanical explanation is given in support of the form of Jastrow wavefunction introduced by De Michelis and Reatto. We propose a new, simpler wavefunction which has the correct long-range behaviour.     

Epistemic Entanglement due to Non-generating Partitions of Classical Dynamical Systems

Quantum entanglement relies on the fact that pure quantum states are dispersive and often inseparable. Since pure classical states are dispersion-free they are always separable and cannot be entangled. However, entanglement is possible for epistemic, dispersive classical states. We show how such epistemic entanglement arises for epistemic states of classical dynamical systems based on phase space partitions that are not generating. We compute epistemically entangled states for two coupled harmonic oscillators.     

Direct calculation of fluctuation formulae in the microcanonical ensemble

We present simple derivations of the classical microcanonical ensemble formulae for fluctuations which involve the kinetic energy and microscopic pressure function. The new derivations, which confirm earlier results of Lebowitz et al. [1] and Cheung [2], proceed in a direct way from basic microcanonical ensemble theory without recourse to fluctuation expressions of other ensemble theories. The method developed is applicable to shell ensembles in general.     

Detecting subthreshold events in noisy data by symbolic dynamics

We show that a symmetric threshold crossing detector can be described by a symbolic dynamics of a static three-symbol encoding which is highly efficient to detect subthreshold events in noisy nonstationary data. After computing instantaneous word statistics and running cylinder entropies, we introduce a mean-field transformation of the three-symbol dynamics considered as a Potts-spin lattice onto a distribution of two symbols. This transformed word statistics enables one to derive an estimator of the signal-to-noise ratio (SNR). Subthreshold events are then proven by a prominent peak of the SNR estimator as a function of the noise intensity.