## The Quantum Mystery of Wigner’s Friend

In this Insight I will introduce the quantum mystery called “Wigner’s friend” using Healey’s version [1] of Frauchiger and Renner’s version [2] of Wigner’s version [3]. As with much of physics, the explication becomes more succinct and comprehensible with each successive rendering. As in my previous Insights, I will show how this mystery results from […]

PhD in general relativity (1987), researching foundations of physics since 1994.