QuantumT Posted March 17, 2019 Posted March 17, 2019 Quote The idea that observers can ultimately reconcile their measurements of some kind of fundamental reality is based on several assumptions. The first is that universal facts actually exist and that observers can agree on them. But there are other assumptions too. One is that observers have the freedom to make whatever observations they want. And another is that the choices one observer makes do not influence the choices other observers make—an assumption that physicists call locality. If there is an objective reality that everyone can agree on, then these assumptions all hold. But Proietti and co’s result suggests that objective reality does not exist. In other words, the experiment suggests that one or more of the assumptions—the idea that there is a reality we can agree on, the idea that we have freedom of choice, or the idea of locality—must be wrong. Full summary: https://www.technologyreview.com/s/613092/a-quantum-experiment-suggests-theres-no-such-thing-as-objective-reality/ Paper: https://arxiv.org/abs/1902.05080
Pablo2019 Posted March 17, 2019 Posted March 17, 2019 The results presented by this experiment are related to the famous Bohr-Einstein debates on the ultimate reality. It can also be tied to Schrodinger's cat thought experiment. Wigner made it more interesting by including, not only the observer and the observed, but also what role consciousness plays in observations and measurements. Some people might find these results compatible with the Many-World interpretation of quantum mechanics. Others would rather prefer the concept of "freedom of choice" to be either altered or abandoned. Now, I ask if objective reality doesn't exist, what do we mean by objective reality? Is a reality based on physical quantities a paradox for science? Does it mean that our interpretations of mathematical formulas are not unique?
koti Posted March 17, 2019 Posted March 17, 2019 I haven't red the paper yet but I'm having problems parsing the word "reality" in this context as it can be highly subjective.
MigL Posted March 17, 2019 Posted March 17, 2019 Two of the premises are probably wrong. There is most likely no reality we can all agree on, as we base 'reality' on the experiments/measurements we perform, and these are subject to the constraints outlined in the OP. As for freedom of choice, I would think Heisenberg turns that on its head; some things we just cannot know. ( Can't throw out the idea of locality though; that would cause even more problems with 'reality' ) that leaves the choices that there is no 'actual' reality, or that we are forbidden to realise what it is.
QuantumT Posted March 17, 2019 Author Posted March 17, 2019 24 minutes ago, MigL said: Two of the premises are probably wrong. There is most likely no reality we can all agree on, as we base 'reality' on the experiments/measurements we perform, and these are subject to the constraints outlined in the OP. As for freedom of choice, I would think Heisenberg turns that on its head; some things we just cannot know. ( Can't throw out the idea of locality though; that would cause even more problems with 'reality' ) that leaves the choices that there is no 'actual' reality, or that we are forbidden to realise what it is. Basically it just means that Schrödinger's Cat's life depends on who's opening the box. If it's dead when Alice opens it, it will be alive again when Bob does it shortly after. Good for the cat, bad for objective reality.
studiot Posted March 17, 2019 Posted March 17, 2019 1 hour ago, QuantumT said: But there are other assumptions too. ....................................................... And another is that the choices one observer makes do not influence the choices other observers make I agree this But not this 2 hours ago, QuantumT said: But there are other assumptions too. One is that observers have the freedom to make whatever observations they want.
QuantumT Posted March 19, 2019 Author Posted March 19, 2019 If the results of this experiment holds - if it can be reproduced with even higher certainty - does it not mean that a particle's superposition returns, after the measurement stops? In other words: That the particle only has a fixed spin direction, when it's measured?
QuantumT Posted June 16, 2019 Author Posted June 16, 2019 (edited) On 3/19/2019 at 8:41 PM, studiot said: Were you going to address my question? Sorry for not replying. I was not notified about your message, and you were (previously) quoting the article, not my words. I'm just the messenger. My interpretation of this, is that it confirms "the observer effect", just like the delayed choice quantum eraser experiment does. So we have two different experiments that contradict the "measurement effect". Two different experiments that shift the culprit from the instruments to the scientists themselves. Edited June 16, 2019 by QuantumT
swansont Posted June 16, 2019 Posted June 16, 2019 19 minutes ago, QuantumT said: I'm just the messenger. ! Moderator Note In that case this should have been posted in science news rather than in physics. Moved.
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