# Foundations of quantum physics II. The thermal interpretation

## TL;DR

This paper introduces the thermal interpretation of quantum physics, providing a new realistic foundation that connects theory with experiment, addresses foundational issues, and clarifies the interpretation of quantum mechanics and quantum field theory.

## Contribution

It proposes the thermal interpretation as an alternative foundation for quantum physics, resolving foundational problems and aligning theory with experimental practice.

## Key findings

- Provides a realistic interpretation connecting quantum theory to experiments.
- Addresses limitations of Born's rule as a foundational principle.
- Clarifies the interpretational differences between quantum mechanics and quantum field theory.

## Abstract

This paper presents the thermal interpretation of quantum physics. The insight from Part I of this series that Born's rule has its limitations -- hence cannot be the foundation of quantum physics -- opens the way for an alternative interpretation -- the thermal interpretation of quantum physics. It gives new foundations that connect quantum physics (including quantum mechanics, statistical mechanics, quantum field theory and their applications) to experiment. The thermal interpretation resolves the problems of the foundations of quantum physics revealed in the critique from Part I of this series. It improves the traditional foundations in several respects: * The thermal interpretation reflects the actual practice of quantum physics, especially regarding its macroscopic implications. * The thermal interpretation gives a fair account of the interpretational differences between quantum mechanics and quantum field theory. * The thermal interpretation gives a natural, realistic meaning to the standard formalism of quantum mechanics and quantum field theory in a single world, without introducing additional hidden variables. * The thermal interpretation is independent of the measurement problem. The latter becomes a precise problem in statistical mechanics rather than a fuzzy and problematic notion in the foundations. Details will be discussed in Part III.