Editing Wigner's friend (section)

===Reflection===
The meaning and implications of the Frauchiger–[[Renato Renner|Renner]] thought experiment are highly debated. A number of assumptions taken in the argument are very foundational in content and therefore cannot be given up easily. However, the question remains whether there are "hidden" assumptions that do not explicitly appear in the argument. The authors themselves conclude that "quantum theory cannot be extrapolated to complex systems, at least not in a straightforward manner".<ref name=":2" /> On the other hand, one presentation of the experiment as a quantum circuit models the agents as single [[qubit]]s and their reasoning as simple conditional operations.<ref>{{cite web |last=Musser |first=George |author-link=George Musser |date=December 24, 2019 |title=Watching the Watchmen: Demystifying the Frauchiger-Renner Experiment |url=https://fqxi.org/community/forum/topic/3354 |access-date=December 28, 2019 |website=FQXi.org}}</ref>

QBism, [[relational quantum mechanics]] and the [[De Broglie–Bohm theory]] have been argued to avoid the contradiction suggested by the extended Wigner's-friend scenario of Frauchiger and Renner.<ref>{{Cite journal |last=Pusey |first=Matthew F. |date=2018-09-18 |title=An inconsistent friend |journal=[[Nature Physics]] |language=en |volume=14 |issue=10 |pages=977–978 |bibcode=2018NatPh..14..977P |doi=10.1038/s41567-018-0293-7 |issn=1745-2473 |s2cid=126294105}}</ref><ref>{{Cite journal |last1=DeBrota |first1=John B. |last2=Fuchs |first2=Christopher A. |last3=Schack |first3=Rüdiger |date=2020-08-18 |title=Respecting One's Fellow: QBism's Analysis of Wigner's Friend |journal=Foundations of Physics |volume=50 |issue=12 |pages=1859–1874 |doi=10.1007/s10701-020-00369-x |arxiv=2008.03572 |bibcode=2020FoPh...50.1859D |s2cid=225377742 |issn=0015-9018}}</ref><ref>{{Cite journal |last1=Waaijer |first1=Marijn |last2=Neerven |first2=Jan van |date=2021 |title=Relational Analysis of the Frauchiger–Renner Paradox and Interaction-Free Detection of Records from the Past |journal=Foundations of Physics |volume=51 |issue=2 |page=45 |doi=10.1007/s10701-021-00413-4 |bibcode=2021FoPh...51...45W |s2cid=226191636 |issn=0015-9018|doi-access=free |arxiv=1902.07139 }}</ref><ref>{{Cite journal |last1=Lazarovici |first1=Dustin |last2=Hubert |first2=Mario |date=2019 |title=How Quantum Mechanics can consistently describe the use of itself |journal=Scientific Reports |volume=9 |issue=470 |page=470 |doi=10.1038/s41598-018-37535-1 |pmid=30679739 |bibcode=2019NatSR...9..470L |s2cid=53685556 |issn=2045-2322|doi-access=free |pmc=6346061 }}</ref>