Real surreal trajectories in pilot-wave hydrodynamics

TL;DR

This paper demonstrates that classical trajectories in pilot-wave hydrodynamics can exhibit features similar to surreal Bohmian trajectories, challenging misconceptions about their non-reality and classical limitations.

Contribution

It provides experimental and numerical evidence that classical pilot-wave systems can produce surreal-like trajectories, clarifying misconceptions about Bohmian mechanics.

Findings

Hydrodynamic trajectories exhibit surreal features.

Surreal trajectories are explained by non-Markovian dynamics.

Challenges misconceptions about Bohmian trajectories.

Abstract

In certain instances, the particle paths predicted by Bohmian mechanics are thought to be at odds with classical intuition. A striking illustration arises in the interference experiments envisaged by Englert, Scully, S\"ussmann and Walther, which lead the authors to claim that the Bohmian trajectories can not be real and so must be `surreal'. Through a combined experimental and numerical study, we here demonstrate that individual trajectories in the hydrodynamic pilot-wave system exhibit the key features of their surreal Bohmian counterparts. These real surreal classical trajectories are rationalized in terms of the system's non-Markovian pilot-wave dynamics. Our study thus makes clear that the designation of Bohmian trajectories as surreal is based on misconceptions concerning the limitations of classical dynamics and a lack of familiarity with pilot-wave hydrodynamics.