From the universe to subsystems: Why quantum mechanics appears more stochastic than classical mechanics

TL;DR

This paper explores the transition from universal laws to subsystem dynamics in classical and quantum mechanics, clarifying how probabilities emerge and differ in these frameworks, with insights from Boltzmann's ideas.

Contribution

It provides a comparative analysis of classical and Bohmian quantum mechanics, elucidating the origin and nature of probabilities in subsystem evolution.

Findings

Probabilities arise from the reduction of universal laws to subsystem dynamics.

Quantum probabilities differ from classical ones in their origin and interpretation.

The paper clarifies how stochasticity appears more prominently in quantum mechanics.

Abstract

By means of the examples of classical and Bohmian quantum mechanics, we illustrate the well-known ideas of Boltzmann as to how one gets from laws defined for the universe as a whole to dynamical relations describing the evolution of subsystems. We explain how probabilities enter into this process, what quantum and classical probabilities have in common and where exactly their difference lies.