Existence of an information unit as a postulate of quantum theory

TL;DR

This paper demonstrates that quantum theory can be derived from the existence of an information unit, along with assumptions of continuous, reversible dynamics and local state characterization, establishing a deep link between physics and information.

Contribution

It introduces a new set of postulates for quantum theory based solely on the existence of an information unit and natural assumptions, simplifying its foundational basis.

Findings

Quantum theory derived from information unit postulate

Establishes a connection between physics and information

Provides a simple physical interpretation of quantum postulates

Abstract

Does information play a significant role in the foundations of physics? Information is the abstraction that allows us to refer to the states of systems when we choose to ignore the systems themselves. This is only possible in very particular frameworks, like in classical or quantum theory, or more generally, whenever there exists an information unit such that the state of any system can be reversibly encoded in a sufficient number of such units. In this work we show how the abstract formalism of quantum theory can be deduced solely from the existence of an information unit with suitable properties, together with two further natural assumptions: the continuity and reversibility of dynamics, and the possibility of characterizing the state of a composite system by local measurements. This constitutes a new set of postulates for quantum theory with a simple and direct physical meaning, like the ones of special relativity or thermodynamics, and it articulates a strong connection between physics and information.