# Tag Info

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Short answer: the cat isn't dead and alive. It's dead or alive. When faced with a quantum superposition of more than one state, e.g., $$|\phi\rangle = \frac{1}{\sqrt{2}}\left(|a\rangle + |b\rangle\right),$$ interpret the plus to mean that when measured the state could be found to be $a$ or $b$, with probabilities governed by the Born rule (i.e., 1/2 in ...

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I feel like all the answers here are missing the point. The cat is not both alive and dead at the same time. That would be, as you put it, ludicrous. The truth is that the cat is in a superposition state of the states "alive" and "dead". The problem is that there is no way to make sense of this statement without studying the underlying mathematics. Humans ...

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The cat is not dead or alive at the same time. This is because the cat is not an isolated quantum system that doesn't interact with the universe (experts say, the decoherence time of the cat is extremely small of the order of $10^{-40}$ s, see e.g. https://arxiv.org/pdf/quant-ph/0306072.pdf p.14 ). But your knowledge about the state of the cat is incomplete. ...

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How can Schrödinger's cat be both dead and alive? It is necessary to say once more that Schrodinger's cat is a bad example of quantum mechanical concepts. What is the quantum mechanical experiment? The decay of a particle which, detected by a detector triggers a poison. The cat is inhumanely used as a magnifier of that trigger. If instead of the series: ...

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It isn't - or, better, a cogent understanding of quantum theory says we cannot completely know in this case, what is going on inside the box, without opening it up. I have long maintained for a while that the crucial distinction between "classical" and "modern" physics is not so much something like "absolute space and time" vs. "relative and 'gooey' space ...

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I think there are some facts you should know before understanding this answer. Einstein and Schrödinger used the thought experiment to "explain" a point that was wrong. They thought it was absurd for quantum mechanics to say that the state a|alive⟩+b|dead⟩ was possible in Nature (it was claimed to be possible in quantum mechanics) because it allowed the both ...

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I'll try to answer this without mathematics or sophistry. If it doesn't quite make sense as a result, ask for clarification. This stuff isn't easy to make sense of. So I'm sorry I'd this is a bit of a long answer! Schroedinger's cat is a way to visualise something that we usually only observe at subatomic level, in a more everyday context. That's actually ...

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Schrödinger's Cat paradox can best explained by color inter-mixing. Suppose we have plate which side is either black or blue: Now we start rotating circularly this plate at high speed. What happens then with edge color ? Rotating plate viewed directly: Now you see that plate side is half-black AND half-blue at the same time ! This corresponds to a cat ...

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Schrodinger's cat is an exercise in seeing how nonsensical the Copenhagen interpretation is, so answers that attempt to clarify it in terms of CI are not very helpful, in my opinion. As a framework for this answer, I'll repeat a point I make frequently: QM describes not the probabilistic evolution of a single deterministic state, but rather the ...

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Forgive the length. I find Schrödinger's cat is much easier to make sense of as a journey through QM, rather than just a few equations that someone says "solves your problems." Schrödinger's cat was definitely meant to be taken seriously, in that it was intended to be a serious challenge to naively applying the Copenhagen interpretation to macroscopic ...

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Basically the answer is yes, the cat is both dead and alive. People used to discuss this sort of thing in terms of the Copenhagen interpretation (CI) and the Many-Worlds interpretation (MWI), but those discussions tend not to be satisfying, because both CI and MWI are designed so that in almost all real-world measurements, they give the same predictions. A ...

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Remember Heisenberg's idea that you can't always measure position and velocity at the same time? So here's an electron, and there's stuff you are guaranteed not to know about it. You can know something about some combination of position and velocity, but that's like having one equation in two unknowns. You know something but you can't solve it like you ...

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Before reading this answer (and to those who are downvoting), I am addressing if the cat is both alive and dead. I don't think the question is asking for a complete explanation of the Schrodinger's cat experiment, nor is it asking how this links to all of the deeper mysteries of quantum mechanics and how we should think of them. Therefore, while there is ...

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At one point it argues that the reason an electron in the double slit experiment has its wave function collapsed when detected before entering one slit or the other is due to the photons fired at it to detect its position having momentum and physically interacting with it. This can't be the reason. Imagine that I have two light sources, one at each slit. ...

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