My undergraduate thesis titled “A Review On Quantum Decoherence” (in Farsi) can be found here. Also, the slides of my 10-minutes-long talk on this work (in English) can be found here.
Abstract: The manner in which states of some quantum systems become effectively classical is of great significance for the foundations of quantum physics, as well as for problems of practical interest such as building quantum gates or quantum computers. In the past three decades, it has become increasingly clear that many of the symptoms of classicality can be induced in quantum systems as a result of the interaction (i.e. not being isolated). Thus, decoherence is caused by the interaction with the surrounding environment. During the course of quantum decoherence only states in the invariant subspace of the system-environment Hamiltonian will remain unchanged as the result of this interaction; Hence, these states are the only ones that can be observed classically. As the result of this environment-induced “super selection”, a vast majority of the Hilbert space will be banned and the classical structure of the “Phase Space” will emerge from the quantum Hilbert space in the macroscopic limit. Also, when the measured quantum system is microscopic and (approximately) isolated, correlation with the macroscopic apparatus will result in the “effective collapse of the wave function”.
Some useful links and papers on Quantum Decoherence and Quantum Darwinism can be found here: