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Published online 22 November 2007 | Nature | doi:10.1038/news.2007.277
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Schrödinger's kittens enter the classical world
Theory shows how quantum weirdness could still be seen on a large scale.
The particles that make up the world obey the rules of quantum theory, allowing them to do counterintuitive things such as being in several different places or states at once, so why don’t we see this sort of bizarre behaviour in the world around us? The explanation commonly offered in physics textbooks is that quantum effects apply only at very small scales, and get smoothed away at the everyday scales we can perceive.
But that’s not necessarily so, say two physicists in Austria.
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The real problem, I think, lies in the bottle of poison. If the bottle of poison breaks then it creates sound and a little heat.
There are several reports that reproduces laws of classical mechanics, Lagranges equation to Eulars theorem starting from uncertainty principle. Therefore, I believe that the whole story could be reframed from different outlook. Klofner and Brukner has seemingly mimicked the same old results to those who reported above works, I dont site any papers here, as they are in abundance in literatures. None of the conclusions drawn by them are one step forward. Fuzzyness in measurement equivalent to scaling transition from quantum to classical has been established time and again not in Schrondingers cat but in many others cases. A note to them would have been better.
Dear Menser, Bottol of poison can not generate heat and sound, because you break the basic principle of the thought experiment, that is, no principle would go against the survival of the universe, wherein the experiment is being made. Therefore, poison bottol can not have any energy, its a switch that responds to the hammer once radioactive particle hits the hammer. Do not please jump on alfa particle and hammer collision. K and B is interested in different issue, and that has much important appeal, they want to mimic classicality inside quantum experiment, thats a brilliant approach, if succeeds, please see that, I am sorry if I hurt you. Anirban
This line of thinking does not take into account the very real effect of the observer on the observed.
Pity, that the cat is an observer.
I would like any physicist anywhere in the world to define THINKING. The problem is these people do not know the definition of THINKING. This explains why they come up with such ridiculous paradoxes. THINKING is not a factor particles. It is a function of WAVES. I'd like to be CHALLENGED! Professor Momoh-Sellu Sua Laye The Dohgon University of Thought
In looking at the last statement of the article, “but in a new state that has no counterpart in classical physics.�, I am wondering if this is quite accurate, at least in terms of the word phrasing. Is it perhaps more correct to say that what is new or different is that there is actually no "state" in the strict sense, meaning that circumstances remain unfixed, not specifically defined. Classical physics does not know how to deal with that since it tends to define time, location, etc, as highly defined quanta. Things are simply undefined.
I would say, and please correct me if I'm wrong, that these two scientists are just expanding on Heisenberg's Uncertainty Principle. By the way, I'm not diminishing the importance of this new theory, I'm just trying to grasp the situation. So, if quantum states could actually be seen and measured as accurately as possible, I believe that Kofler and Brukner are suggesting that we could actually measure the uncertainty of an object that is constantly changing phases and actually be able to see it change, as we would get closer to actually see the quantum particles switching from a wave to a particle, and viceversa. The basic idea I think is that we could do this with any object of any size only by making our measurements more accurate so that we can actually observe this phase change.