Autonomy all the way down: Systems and dynamics in quantum Bayesianism

TL;DR

This paper critically examines Quantum Bayesianism (QBism), revealing that it faces similar foundational issues as traditional quantum theories, thereby providing insights into quantum foundations.

Contribution

The paper demonstrates that QBism encounters its own foundational problems, offering new perspectives on quantum theory foundations beyond traditional approaches.

Findings

QBism has its own versions of foundational problems.

These problems are illuminating for understanding quantum theory.

The analysis applies insights to both QBism and traditional quantum foundations.

Abstract

Quantum Bayesianism ("QBism") has been put forward as an approach to quantum theory that avoids foundational problems by altogether disavowing the objective existence of quantum states. It is shown that QBism suffers its own versions of the familiar foundational problems, and that these QBist versions are illuminating not just for QBism, but for more traditional foundational approaches as well.