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Inquiring minds want to know what Schrödinger's cat is all about, how it relates to quantum mechanics, and superposition.
Inquiring minds want to know what Schrödinger's cat is all about, how it relates to quantum mechanics, and superposition.
Schrodinger's Cat is just a way of saying that you don't know which way something is until you settle the question by finding out. Finding out whether the cat is dead or alive is comparable to peaking out your window and finding out whether it's sunny or cloudy. Nothing mysterious is going on. Superposition is just a way of expressing the possible observations, along with their probabilities of occurring, as a single mathematical entity. It would be very fanciful to think that the cat is both alive and dead before you look at it, and that your looking at it causes it to die all the way or come entirely back to life.
It's worth mentioning that there are some observations, though, in which the means of making the observation does play a causal role on the thing being observed; e.g. your walking into a room full of people will allow you to see who is in the room, and your presence there as an observer will also effect what you see the people doing; some of them will likely glance in your direction, and more subtly, your vantage point itself will allow you to see some things while other things remain hidden from you. This kind of thing is a major point in physics, where the goal of an experiment is to get an observation of phenomena as they actually are, independent of any subjective influence. Scientists have found that this is impossible, because the tools that they use to make an observation will, like a person walking into a room and looking around him, always in some subtle way decide what they end up seeing. Schrodinger's Cat is not a very good way of illustrating this, though, because the cat is killed or given a reprieve by the box, not by the person who opens it. If the cat's life hinged (literally) on some mechanism in the hinges of the box, it would be a more apt illustration of how observing something determines, even if only in an extremely passive sense, what is observed.
Heisenberg's discovery is related to Schrodinger's Cat in that they both illustrate the connection between observation and what is observed. The difference between them is that Heisenberg's discovery strictly concerns the role of observation, where Schrodinger's Cat is focused as much on that as it is on the state of uncertainty (called a superposition when mathematically formalized along with the probabilities of different resolutions for that state of uncertainty) that precedes an observation.SRT said:Wasn't Heisenberg the one who discovered that the act of observing particles in motion affect their trajectory? I don't think it has much to do with Schrodinger's cat. But then again my knowledge of physics is pretty poor.
Wasn't Heisenberg the one who discovered that the act of observing particles in motion affect their trajectory? I don't think it has much to do with Schrodinger's cat.
How much understanding do you have of differential equations and basic statistics?
If not, do you have any stringed instruments?
Note about Polaris' post. It is not about human 'observation'. The superposition can decohere into a definite eigenstate due to quantum interactions, regardless of whether this interaction is formally observed or not. The interesting point is that we can only associate the system with a definite eigenstate at the moment of interaction. At other times, a superposition is a more natural assumption, at least if you discard classical notions of physics.
A statistical view is deemed acceptable in most sciences, so why not physics?
It's a thought experiment Schrodinger came up with to try to disprove the Copenhagen interpretation.Inquiring minds want to know what Schrödinger's cat is all about, how it relates to quantum mechanics, and superposition.
If you're required to interact with an object in order to determine which eigenstate it possesses, that illustrates the role of observation in exactly the way I described. Undoubtedly there are some cases where interacting with an object has negligible effects on it--this is a type of situation I outlined in my post--but there are also cases where the act of observation plays a tangible role on the object's state itself (by way of observation's means of observing). As far as I can tell, Copenhagen's ideas are a scientific elaboration on this latter kind of case, whereas Schrodinger's Cat illustrates a case in which there is no decisive role being played either by observation's means of observation or by any other physical entities; the object's state at such a moment can only be determined as a range of mutually exclusive possibilities, called a superposition.Note about Polaris' post. It is not about human 'observation'. The superposition can decohere into a definite eigenstate due to quantum interactions, regardless of whether this interaction is formally observed or not. The interesting point is that we can only associate the system with a definite eigenstate at the moment of interaction. At other times, a superposition is a more natural assumption, at least if you discard classical notions of physics.