# Single-world interpretations of quantum theory cannot be self-consistent

**Authors:** Daniela Frauchiger, Renato Renner  
**arXiv:** [1604.07422](https://arxiv.org/abs/1604.07422)  
**Date:** 2016-04-25  
**Summary page:** https://www.summarizepaper.com/en/arxiv-id/1604.07422v1/

## Key points

- The paper explores the concept of single-world interpretations in quantum theory.
- Single-world interpretation suggests that a measurement can have multiple possible outcomes but only one of them "really" occurs.
- The authors propose a gedankenexperiment to model an experimenter who also uses quantum theory and find that no single-world interpretation can be logically consistent in such a scenario.
- This conclusion extends to deterministic hidden-variable theories like Bohmian mechanics since they also impose a single-world interpretation.
- The findings challenge the traditional understanding of quantum mechanics and suggest that alternative interpretations may need to be considered.
- The paper has been published in Nature Communications.

## Summary

In their paper titled "Single-world interpretations of quantum theory cannot be self-consistent," Daniela Frauchiger and Renato Renner explore the concept of single-world interpretations in quantum theory. According to this interpretation, a measurement can have multiple possible outcomes but only one of them "really" occurs. The authors propose a gedankenexperiment where quantum theory is used to model an experimenter who also uses quantum theory. They find that in such a scenario, no single-world interpretation can be logically consistent. This conclusion extends to deterministic hidden-variable theories like Bohmian mechanics since they also impose a single-world interpretation. The findings of Frauchiger and Renner challenge the traditional understanding of quantum mechanics and suggest that alternative interpretations may need to be considered. Their work has been published in Nature Communications and provides valuable insights into the fundamental nature of reality as described by quantum mechanics.