# The Open Systems View and the Everett Interpretation

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## Abstract

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## 1. Introduction

## 2. The General Quantum Theory of Open Systems

A system-theoretic description of an open system has to be considered as phenomenological; the requirement that it should be derivable from the fundamental automorphic dynamics of a closed system implies that the dynamical map of an open system has to be completely positive(p. 435, our emphasis).

## 3. The Open Systems View and the Everett Interpretation

[i]nvoking it seems to compromise a chief selling point of the Everett interpretation, which is that many-worlds follows from the unitary dynamics, with no added principles or special assumptions. This is what puts the Everett interpretation in a class of its own when it comes to the quantum realism problem: there are plenty of avenues for obtaining (at least non-relativistic) one-world theories if we are prepared to violate this precept.([25], p. 193).

## 4. Conclusions

## Author Contributions

## Funding

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

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**MDPI and ACS Style**

Cuffaro, M.E.; Hartmann, S.
The Open Systems View and the Everett Interpretation. *Quantum Rep.* **2023**, *5*, 418-425.
https://doi.org/10.3390/quantum5020027

**AMA Style**

Cuffaro ME, Hartmann S.
The Open Systems View and the Everett Interpretation. *Quantum Reports*. 2023; 5(2):418-425.
https://doi.org/10.3390/quantum5020027

**Chicago/Turabian Style**

Cuffaro, Michael E., and Stephan Hartmann.
2023. "The Open Systems View and the Everett Interpretation" *Quantum Reports* 5, no. 2: 418-425.
https://doi.org/10.3390/quantum5020027