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Decoherence Functional and Inhomogeneities in the Early Universe

R. Laflamme·A. Matacz
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Abstract

We investigate the quantum to classical transition of small inhomogeneous fluctuations in the early Universe using the decoherence functional of Gell-Mann and Hartle. We study two types of coarse graining; one due to coarse graining the value of the scalar field and the other due to summing over an environment. We compare the results with a previous study using an environment and the off-diagonal rule proposed by Zurek. We show that the two methods give different results.

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R. Laflamme, A. Matacz. 1993-03-30. Decoherence Functional and Inhomogeneities in the Early Universe. https://doi.org/10.1142/s0218271893000155

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