Showing posts with label Quantum Mystery. Show all posts
Showing posts with label Quantum Mystery. Show all posts

Tuesday, March 26

The Quantum Though Experiment




Quantum mystery In 1961 Eugene Wigner imagined a friend doing an experiment in a lab while he waits outside. The paradox is that Wigner and the friend predict different outcomes, yet both are right. (iStock/Floriana)








“Wigner’s friend” is a curious thought experiment that has stumped physicists and philosophers for more than 60 years. Robert P Crease, Jennifer Carter and Gino Elia advise on how to resolve this conundrum.

The quantum world provides fertile material for thought experiments that seem so strange-but-true as to defy logic. One of the most notorious is “Wigner’s friend”, which has challenged physicists and philosophers ever since it was first conceived by the Hungarian-American physicist Eugene Wigner. He published the thought experiment in a 1961 book edited by the mathematician Irving Good entitled The Scientist Speculates: an Anthology of Partly-baked Ideas.

Wigner’s thought experiment is a more humane version of Schrödinger’s less complex but more famous thought experiment a quarter century before, which involved a cat inside a box whose fate hangs on a quantum event. Inside the box Schrödinger’s cat is dead or alive, whereas for someone outside, the cat remains dead-and-alive; it’s in a “superposition”. The bizarre situation only vanishes when the box lid opens.     READ MORE...