Intrinsically Quantum-Mechanical Gravity and the Cosmological Constant Problem

Abstract

We propose that gravity be intrinsically quantum-mechanical, so that in the absence of quantum mechanics the geometry of the universe would be Minkowski. We show that in such a situation gravity does not require any independent quantization of its own, with it being quantized simply by virtue of its being coupled to the quantized matter fields that serve as its source. We show that when the gravitational and matter fields possess an underlying conformal symmetry, the gravitational field and fermionic matter-field zero-point fluctuations cancel each other identically. Then, when the fermions acquire mass by a dynamical symmetry breaking procedure that induces a cosmological constant in such conformal theories, the zero-point fluctuations readjust so as to cancel the induced cosmological constant identically. The zero-point vacuum problem and the cosmological constant vacuum problems thus mutually solve each other. We illustrate our ideas in a completely solvable conformal-invariant model, namely two-dimensional quantum Einstein gravity coupled to a Nambu-Jona-Lasinio self-consistent fermion.

15 pages. Presentation at the International Conference on Two Cosmological Models, Universidad Iberoamericana, Mexico City, November 17-19, 2010. Updated final version, contains many new footnotes, no major changes. To appear in Mod. Phys. Lett. A

References in corpus (3)

• No-ghost theorem for the fourth-order derivative Pais-Uhlenbeck oscillator model
• Exactly solvable PT-symmetric Hamiltonian having no Hermitian counterpart
• Comprehensive Solution to the Cosmological Constant, Zero-Point Energy, and Quantum Gravity Problems

Cited by in corpus (10)

• Making the Case for Conformal Gravity
• Fitting galactic rotation curves with conformal gravity and a global quadratic potential
• Mass Generation, the Cosmological Constant Problem, Conformal Symmetry, and the Higgs Boson
• Cosmological Perturbations in Conformal Gravity
• Lorentz invariance and the zero-point stress-energy tensor
• Conformal Invariance and the Metrication of the Fundamental Forces
• Infrared modification of gravity from conformal symmetry
• The Pauli sum rules imply BSM physics
• QED Vacuum Loops and Dark Energy
• Beyond the standard model with sum rules