Quantum mind cat; he didn't think the cat was literally alive and dead at the same time. This analogy about making a decision uses a formalism that is derived from quantum mechanics, but it doesn't indicate the actual mechanism by which the decision is made. In this way, the idea is similar to quantum cognition. This field clearly distinguishes itself from the quantum mind as it is not reliant on the hypothesis that there is something micro-physical quantum mechanical about the brain. Quantum cognition is based on the quantum-like paradigm, generalized quantum paradigm, or quantum structure paradigm that information processing by complex
Measurement in quantum mechanics bit more convenient to write the Hilbert space as a direct sum of multiple eigen"spaces". The probability of measuring a particular eigenvalue is the squared component of the state vector in the corresponding eigenspace, and the new state after measurement is the projection of the original state vector into the appropriate eigenspace. Instead of performing quantum-mechanics computations in terms of wave functions (kets), it is sometimes necessary to describe a quantum-mechanical system in terms of a density matrix. The analysis in this case is formally slightly different, but the physical content is the same, and indeed this case can be