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Can we (in principle) put a cat into a pure quantum state, without killing the cat?
dextercioby said:And how would you do that,namely putting the cat in the "pure" quantum state...?
Daniel.
dextercioby said:I don't know,i've always though that asserting QM principles and rationales to a macroscopic (hence (very) many particle system) would lead nowhere...
In this line of logics,you might even suggest computing the "pure" quantum state of the cat at a moment "t" by applying the cat's evolution operator on the cat's ket at the moment "t_{0}"... :tongue2: :rofl:
Daniel.
dextercioby said:I don't know,i've always though that asserting QM principles and rationales to a macroscopic (hence (very) many particle system) would lead nowhere...
In this line of logics,you might even suggest computing the "pure" quantum state of the cat at a moment "t" by applying the cat's evolution operator on the cat's ket at the moment "t_{0}"... :tongue2: :rofl:
Daniel.
dextercioby said:Of course,by that "nowhere" i meant it cannot make predictions with the same accuracy like in the case of very simple quantum systems...IIRC,not even the Helium atom would be totally predictable...
Anyway,apparently sA has given u some kind of answer you were looking after...
Daniel.
pervect said:Can we (in principle) put a cat into a pure quantum state, without killing the cat?
Assuming the cat can be described by a density matrix, and the density matrix being a symmetric matrix, it can be diagonalized in a certain basis of its hilbert state. At that point, we can say that the cat is in one of these states, but we lack knowledge of which one, which is described by the values on the diagonal of the matrix.
slyboy said:The problem with that is that the density matrix can be composed into a probablistic mixture of (generally non-orthogonal) pure states in multiple different ways. What leads you to pick one particular decomposition as special?
This concept is known as the Schrödinger's cat thought experiment, where a cat is placed in a sealed box with a device that can release a poison at any moment based on the decay of a radioactive atom. According to quantum mechanics, until the box is opened, the cat exists in a state of being both alive and dead at the same time, known as a superposition.
A pure quantum state is a state in which a quantum system can exist, where its properties (such as position, momentum, etc.) are completely described by a mathematical function known as a wavefunction. This wavefunction can represent all possible states of the system at the same time, known as superposition.
In theory, yes, but in practice, it is highly unlikely. The Schrödinger's cat experiment is a thought experiment and is not meant to be carried out in reality. The principles of quantum mechanics apply to subatomic particles and not macroscopic objects like cats.
The implications are mostly philosophical and theoretical. It challenges our understanding of reality and the role of observation in determining the state of a system. It also raises questions about the boundary between the macroscopic and microscopic worlds and the validity of quantum mechanics at larger scales.
In the context of the Schrödinger's cat experiment, yes, but in reality, this is not possible. The cat will be either alive or dead when the box is opened and observed. The superposition state only exists until the system is observed, and then it collapses into one definite state.