Why there is something rather than nothing (out of everything)?

Abstract

The path integral over Euclidean geometries for the recently suggested density matrix of the Universe is shown to describe a microcanonical ensemble in quantum cosmology. This ensemble corresponds to a uniform (weight one) distribution in phase space of true physical variables, but in terms of the observable spacetime geometry it is peaked about complex saddle-points of the {\em Lorentzian} path integral. They are represented by the recently obtained cosmological instantons limited to a bounded range of the cosmological constant. Inflationary cosmologies generated by these instantons at late stages of expansion undergo acceleration whose low-energy scale can be attained within the concept of dynamically evolving extra dimensions. Thus, together with the bounded range of the early cosmological constant, this cosmological ensemble suggests the mechanism of constraining the landscape of string vacua and, simultaneously, a possible solution to the dark energy problem in the form of the quasi-equilibrium decay of the microcanonical state of the Universe.

4 pages, RevTex, several references added and minor changes done

References in corpus (8)

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Cited by in corpus (26)

• Inflation scenario via the Standard Model Higgs boson and LHC
• Quantum geometrodynamics: whence, whither?
• Tunneling cosmological state revisited: Origin of inflation with a non-minimally coupled Standard Model Higgs inflaton
• Quantum cosmology and late-time singularities
• Darkness without dark matter and energy -- generalized unimodular gravity
• Anomaly Driven Cosmology: Big Boost Scenario and AdS/CFT Correspondence
• Origin of inflation in CFT driven cosmology: $R^2$-gravity and non-minimally coupled inflaton models
• CFT driven cosmology and the DGP/CFT correspondence
• CFT driven cosmology and conformal higher spin fields
• Creation of entangled universes avoids the big bang singularity
• Notes on conformal anomaly, nonlocal effective action and the metamorphosis of the running scale
• Thermal power spectrum in the CFT driven cosmology
• BRST technique for the cosmological density matrix
• New type of hill-top inflation
• Third quantization: modeling the universe as a 'particle' in a quantum field theory of the minisuperspace
• Topological Inflation
• On suppression of topological transitions in quantum gravity
• The path integral for the statistical sum of the microcanonical ensemble in cosmology
• Cosmological Magnetic Field and Dark Energy as two sides of the same coin
• Statistical sum in the CFT driven cosmology
• On the functional determinant of a special operator with a zero mode in cosmology
• Monodromies and functional determinants in the CFT driven quantum cosmology
• Cosmology from Strong Interactions
• Preferred basis, decoherence and a quantum state of the Universe
• Geodesic family of spherical instantons and cosmic quantum creation
• Microcanonical quantum cosmology: gauge fixing and functional determinants on a circle