Is the Copenhagen interpretation inapplicable to Quantum Cosmology?

TL;DR

This paper argues that the core principles of the Copenhagen interpretation, specifically wholeness and complementarity, are applicable to quantum gravity and cosmology through an extended phase space approach, challenging the common view of their inapplicability.

Contribution

It demonstrates that the Copenhagen interpretation's principles can be valid in quantum cosmology using an extended phase space approach aligned with Everett's relative states.

Findings

Copenhagen principles make sense in quantum gravity.

Extended phase space approach aligns with Everett's formulation.

No contradiction between Copenhagen principles and quantum cosmology.

Abstract

It is generally accepted that the Copenhagen interpretation is inapplicable to quantum cosmology, by contrast with the many worlds interpretation. I shall demonstrate that the two basic principles of the Copenhagen interpretation, the principle of wholeness and the principle of complementarity, do make sense in quantum gravity, since we can judge about quantum gravitational processes in the Very Early Universe by their vestiges in our macroscopic Universe. I shall present the extended phase space approach to quantum gravity and show that it can be interpreted in the spirit of the Everett's `relative states' formulation, while there is no contradiction between the `relative states' formulation and the mentioned basic principles of the Copenhagen interpretation.