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تسجيل مستخدم جديدDefinition of a time variable with Entropy of a perfect fluid in Canonical Quantum Gravity
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The Brown-Kuchar mechanism is applied in the case of General Relativity coupled with the Schutz model for a perfect fluid. Using the canonical formalism and manipulating the set of modified constraints one is able to recover the definition of a time evolution operator, i.e. a physical Hamiltonian, expressed as a functional of gravitational variables and the entropy.
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