Emergent modified gravity: Polarized Gowdy model on a torus

Abstract

New covariant theories of emergent modified gravity exist not only in spherically symmetric models, as previously found, but also in polarized Gowdy systems that have a local propagating degree of freedom. Several explicit versions are derived here, depending on various modification functions. These models do not have instabilities from higher time derivatives, and a large subset is compatible with gravitational waves and minimally coupled massless matter fields travelling at the same speed. Interpreted as models of loop quantum gravity, covariant Hamiltonian constraints derived from the covariance conditions found in polarized Gowdy systems are more restricted than those in spherical symmetry, requiring new forms of holonomy modifications with an anisotropy dependence that has not been considered before. Assuming homogeneous space, the models provide access to the full anisotropy parameters of modified Bianchi I dynamics, in which case different fates of the classical singularity are realized depending on the specific class of modifications.

arXiv comment55 pages, two figures

References in corpus (36)

• Multi-messenger Observations of a Binary Neutron Star Merger
• Gravitational Waves and Gamma-rays from a Binary Neutron Star Merger: GW170817 and GRB 170817A
• Swope Supernova Survey 2017a (SSS17a), the Optical Counterpart to a Gravitational Wave Source
• Anomaly-free formulation of non-perturbative, four-dimensional Lorentzian quantum gravity
• Isotropic Loop Quantum Cosmology
• Loop quantization of the Schwarzschild black hole
• Quantum Symmetry Reduction for Diffeomorphism Invariant Theories of Connections
• The Area Operator in the Spherically Symmetric Sector of Loop Quantum Gravity
• Gauge transformations in the Lagrangian and Hamiltonian formalisms of generally covariant theories
• Spherically Symmetric Quantum Geometry: States and Basic Operators
• Spherically Symmetric Quantum Geometry: Hamiltonian Constraint
• Hybrid Quantum Gowdy Cosmology: Combining Loop and Fock Quantizations
• Effective line elements and black-hole models in canonical (loop) quantum gravity
• Loop quantum cosmology and inhomogeneities
• A Neutron Star Binary Merger Model for GW170817/GRB170817a/SSS17a
• An effective model for the quantum Schwarzschild black hole
• Inhomogeneous Loop Quantum Cosmology: Hybrid Quantization of the Gowdy Model
• Towards an Anomaly-Free Quantum Dynamics for a Weak Coupling Limit of Euclidean Gravity
• Covariance in models of loop quantum gravity: Gowdy systems
• Matter in inhomogeneous loop quantum cosmology: the Gowdy $T^3$ model
• Emergent modified gravity: Covariance regained
• Towards an Anomaly-Free Quantum Dynamics for a Weak Coupling Limit of Euclidean Gravity: Diffeomorphism Covariance
• Covariance in self dual inhomogeneous models of effective quantum geometry: Spherical symmetry and Gowdy systems
• Is classical flat Kasner spacetime flat in quantum gravity?
• Singularity resolution by holonomy corrections: Spherical charged black holes in cosmological backgrounds
• The constraint algebra in Smolins' $G\to 0$ limit of 4d Euclidean Gravity
• Loop quantization of the Gowdy model with local rotational symmetry
• Loop Quantization of Polarized Gowdy Model on $T^3$: Kinematical States and Constraint Operators
• Loop Quantization of Polarized Gowdy Model on $T^3$: Classical Theory
• Towards Loop Quantization of Plane Gravitational Waves
• Emergent modified gravity: The perfect fluid and gravitational collapse
• Emergent modified gravity coupled to scalar matter
• Emergent Modified Gravity
• A new type of large-scale signature change in emergent modified gravity
• MONDified Gravity
• The volume operator for singly polarized gravity waves with planar or cylindrical symmetry

Cited by in corpus (1)

• Lessons for loop quantum gravity from emergent modified gravity