Quanta magazine interviewed Princeton physicist, Edward Witten, known for his M-theory, or theory of everything in 2017. Witten sounded perplexed about making sense of physics. He told the interviewer that he was reading an old essay by the 20th-century Princeton physicist John Wheeler and said, “He was a visionary, certainly. If you take what he says literally, it’s hopelessly vague. And therefore, if I had read this essay when it came out 30 years ago, which I may have done, I would have rejected it as being so vague that you couldn’t work on it, even if he was on the right track.”
(Interviewer) You’re referring to “Information, Physics, Quantum”, Wheeler’s 1989 essay propounding the idea that the physical universe arises from information, which he dubbed “it from bit.”
(Witten) When I was a beginning grad student, they had a series of lectures by faculty members to the new students about theoretical research, and one of the people who gave such a lecture was Wheeler. He drew a picture on the blackboard of the universe visualized as an eye looking at itself. I had no idea what he was talking about. It’s obvious to me in hindsight that he was explaining what it meant to talk about quantum mechanics when the observer is part of the quantum system. I imagine there is something we don’t understand about that.
It seems to me that the acceptance and use of quantum physics has come a long way since 2017 when this interview took place, including the seriousness of using quantum computing which is based upon these mysterious principles.
Mystics love this drawing, as it suggests that the eye of God is experiencing itself through its creation.