| The Heisenberg uncertainty principle is the root of the Copenhagen interpretation. The uncertainty principle says you can never know both the location and the momentum of a particle. This stems from the fact that because spacetime is the way it is, knowing either one of those things requires having made a measurement, which by its nature, prevents the measurement of the other thing. The act of measurement is independent of there being an "observer" in the sense of some sort of intelligence or consciousness. The use of the word observer in early communications led to all sorts of woowoo garbage later on. More recent interpretations suggest that instead of the requirement that particles be in a singular state, perhaps their fundamental nature is probabilistic. The wave function is the thing, the particle at a singular place and time is an illusion. There's no need for wave functions to collapse, and that view seems to be an imposition of human scale expectations on the quantum universe. An electron exists as a point cloud - what we observe is an artifact of the observation, not a fundamental property of the particle. I am fond of the "universe is made of math" view suggested by Max Tegmark. https://en.m.wikipedia.org/wiki/Mathematical_universe_hypoth... We did not evolve to perceive the universe as it is. We have limitations built into the mechanics of our existence that have to be overcome and understood at every level of abstraction that our tools of reason and technology provide. The more degrees of separation between our evolved tools of perception and extrapolated and abstracted concepts about how the universe works, the more it will diverge from human experience and seem to be "weird." When we try to make weird things make sense to our monkey brains, we introduce a bias that can lead us astray. https://www.quantamagazine.org/where-quantum-probability-com... The Copenhagen interpretation is an attempt to make monkey sense of something that has no direct input into any of our tools of perception. The Everett interpretation recognizes that any observation has to include the quantum states of the mechanism doing the measuring, the environment in which the mechanism resides, and the entities in proximity to the environment, and planet, solar system, galaxy, and universe - that by existing inside the universe, you are subject to the influence of everything else that exists within the universe, and that quantum states are one of the proxies we have for predicting the results of interactions between the states. Stephen Hawking was an Everettian, and discounted the Copenhagen interpretation. https://en.wikipedia.org/wiki/Many-worlds_interpretation Tldr; there's no such consensus on Copenhagen, and the many worlds interpretation is gaining precedence, because it's got the most rigorous basis in mathematics. |