Variational Approximations for Correlati
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CΓ©cile Martin
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Article
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1999
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Elsevier Science
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English
β 381 KB
Applying the time-dependent variational principle of Balian and Ve ne roni, we derive variational approximations for multi-time correlation functions in 8 4 field theory. We assume first that the initial state is given and characterized by a density operator equal to a Gaussian density matrix. Then,