Covariant Effective Action for Loop Quantum Cosmology a la Palatini

Abstract

In loop quantum cosmology, non-perturbative quantum gravity effects lead to the resolution of the big bang singularity by a quantum bounce without introducing any new degrees of freedom. Though fundamentally discrete, the theory admits a continuum description in terms of an effective Hamiltonian. Here we provide an algorithm to obtain the corresponding effective action, establishing in this way the covariance of the theory for the first time. This result provides new insights on the continuum properties of the discrete structure of quantum geometry and opens new avenues to extract physical predictions such as those related to gauge invariant cosmological perturbations.

5 pages, 1 figure, minor revision to match published version (JCAP), presentation and abstract improved, references added

References in corpus (21)

• Quantum Nature of the Big Bang: Improved dynamics
• Quantum Nature of the Big Bang
• Robustness of key features of loop quantum cosmology
• Limit to General Relativity in f(R) theories of gravity
• Corrections to the Friedmann Equations from LQG for a Universe with a Free Scalar Field
• Non-Singular Bouncing Universes in Loop Quantum Cosmology
• The matter power spectrum in f(R) gravity
• f(R) gravity theories in Palatini formalism: cosmological dynamics and observational constraints
• A no-go theorem for polytropic spheres in Palatini f(R) gravity
• Violation of the Equivalence Principle in Modified Theories of Gravity
• Interacting dark energy in $f(R)$ gravity
• The Cosmology of Ricci-Tensor-Squared Gravity in the Palatini Variational Approach
• Hydrogen atom in Palatini theories of gravity
• The viability of theories with matter coupled to the Ricci scalar
• CMB and Matter Power Spectra of Early f(R) Cosmology in Palatini Formalism
• Curvature singularities, tidal forces and the viability of Palatini f(R) gravity
• Re-examination of Polytropic Spheres in Palatini f(R) Gravity
• The Cauchy problem of f(R) gravity
• Microscopic and Macroscopic Behaviors of Palatini Modified Gravity Theories
• f(R) gravity: successes and challenges
• Non-metric gravity: A status report

Cited by in corpus (100)

• f(R) Theories Of Gravity
• f(R) theories
• Loop Quantum Cosmology: A Status Report
• Dark Energy
• The CosmoVerse White Paper: Addressing observational tensions in cosmology with systematics and fundamental physics
• Bounce cosmology from $F(R)$ gravity and $F(R)$ bigravity
• Are loop quantum cosmos never singular?
• Metric-Palatini gravity unifying local constraints and late-time cosmic acceleration
• Bouncing cosmology in modified Gauss-Bonnet gravity
• Bouncing Cosmologies in Palatini $f(R)$ Gravity
• A bird's eye view of f(R)-gravity
• Deformed General Relativity and Effective Actions from Loop Quantum Gravity
• Charged spherically symmetric black holes in $f(R)$ gravity and their stability analysis
• Physical evolution in Loop Quantum Cosmology: The example of vacuum Bianchi I
• Reissner-Nordström black holes in extended Palatini theories
• Critical evaluation of common claims in loop quantum cosmology
• Anomaly-free cosmological perturbations in effective canonical quantum gravity
• Isotropic and Anisotropic Bouncing Cosmologies in Palatini Gravity
• Hamiltonian Formulation of Palatini f(R) theories a la Brans-Dicke
• Dynamical Aspects of Generalized Palatini Theories of Gravity
• Cosmic recall and the scattering picture of Loop Quantum Cosmology
• Re-examination of Polytropic Spheres in Palatini f(R) Gravity
• Thermodynamics in $f(R)$ gravity in the Palatini formalism
• Contrasting features of anisotropic loop quantum cosmologies: the role of spatial curvature
• Qualitative dynamics and inflationary attractors in loop cosmology
• Bounce universe from string-inspired Gauss-Bonnet gravity
• Properties of a recent quantum extension of the Kruskal geometry
• Holographic actions from black hole entropy
• On $R+\alpha R^2$ Loop Quantum Cosmology
• Brane-world and loop cosmology from a gravity-matter coupling perspective
• Dynamics of Linear Perturbations in the hybrid metric-Palatini gravity
• Palatini frames in scalar-tensor theories of gravity
• Loop quantum $f(R)$ theories
• Nonsingular black holes in quadratic Palatini gravity
• Effective loop quantum cosmology as a higher-derivative scalar-tensor theory
• Big Bounce cosmology for Palatini $R^2$ gravity with a Nieh-Yan term
• Primordial black holes in loop quantum cosmology: The effect on the threshold
• Genericness of pre-inflationary dynamics and probability of the desired slow-roll inflation in modified loop quantum cosmologies
• Dark energy: investigation and modeling
• Semiclassical geons as solitonic black hole remnants
• On stability of a neutron star system in Palatini gravity
• Microscopic wormholes and the geometry of entanglement
• Polytropic stars in Palatini gravity
• Towards a reduced phase space quantization in loop quantum cosmology with an inflationary potential
• Covariant Effective Action for Loop Quantum Cosmology from Order Reduction
• Loop Quantum Cosmology: A brief review
• Dynamical generation of wormholes with charged fluids in quadratic Palatini gravity
• Palatini Actions and Quantum Gravity Phenomenology
• Bouncing Palatini cosmologies and their perturbations
• Filtering out the cosmological constant in the Palatini formalism of modified gravity
• Non-covariance of the dressed-metric approach in loop quantum cosmology
• Transcending Big Bang in Loop Quantum Cosmology: Recent Advances
• Effective interactions in Ricci-Based Gravity models below the non-metricity scale
• Planck scale physics and topology change through an exactly solvable model
• Smoking guns of a bounce in modified theories of gravity through the spectrum of the gravitational waves
• Some conceptual issues in loop quantum cosmology
• Do sewn singularities falsify the Palatini cosmology?
• Inverse problem: Reconstruction of modified gravity action in Palatini formalism by Supernova Type Ia data
• Loop Quantum Cosmology Matter Bounce Reconstruction from $F(R)$ Gravity Using an Auxiliary Field
• Superbounce and Loop Quantum Ekpyrotic Cosmologies from Modified Gravity: $F(R)$, $F(G)$ and $F(T)$ Theories
• Bouncing cosmology in $f(R,\mathcal{G})$ gravity by order reduction
• Quantum gravitational onset of Starobinsky inflation in a closed universe
• Loop quantum gravity, signature change, and the no-boundary proposal
• Stability of Hyperbolic and Matter-Dominated Bounce Cosmologies From F(R,G) Modified Gravity at Late Evolution Stages
• Birth of baby universes from gravitational collapse in a modified-gravity scenario
• Quasi-normal Modes of Static Spherically Symmetric Black Holes in $f(R)$ Theory
• Effective Field Theory of Loop Quantum Cosmology
• Structure formation in $f(R)$ gravity: A distinguishing probe between the dark energy and modified gravity
• Reply to `A comment on `The Cauchy problem of f(R) gravity''
• Gravity as an emergent phenomenon: a GFT perspective
• $f(\mathcal{G},\text{T})$ Gravity Bouncing Universe with Cosmological Parameters
• Cosmological constraints of Palatini $f(\mathcal{R})$ gravity
• Extended Loop Quantum Gravity
• Superradiant (In)stability, Greybody Radiation, and Quasinormal Modes of Rotating Black Holes in non-linear Maxwell f (R) Gravity
• Palatini's cousin: A New Variational Principle
• New Cases of Universality Theorem for Gravitational Theories
• Black hole formation from a null fluid in extended Palatini gravity
• Conformal Metric-Affine Gravities
• Gravitoelectromagnetism in metric f(R) and Brans-Dicke theories with a potential
• The cosmological constant filter without big bang singularity
• Bouncing cosmological models in a functional form of F(R) gravity
• Effective $f(R)$ actions for modified Loop Quantum Cosmologies via order reduction
• Higgs inflation model with non-minimal coupling in hybrid Palatini approach
• Neutron Stars in Palatini $R+\alpha R^2$ and $R+\alpha R^2+\beta Q$ Theories
• A diffeomorphism invariant family of metric-affine actions for loop cosmologies
• Extended Cosmologies
• Asymptotically Weyl-Invariant Gravity
• Loop Quantum Cosmology: Physics of Singularity Resolution and its Implications
• Pulsation of black holes
• Variety of $(d+1)$ dimensional Cosmological Evolutions with and without bounce in a class of LQC -- inspired Models
• The gyroscopic frequency of metric $f(R)$ and generalised Brans-Dicke theories: constraints from Gravity Probe-B
• A Momentous Arrow of Time
• Non-metricity signatures on the Higgs boson signal strengths at the LHC
• Non-singular Universes a la Palatini
• Cosmological dynamics in spin-foam loop quantum cosmology: challenges and prospects
• Isotropic LQC and LQC--inspired Models with a massless scalar field as Generalised Brans--Dicke theories
• On the role of dissipative effects in the quantum gravitational onset of warm Starobinsky inflation in a closed universe
• Palatini approach to bouncing cosmologies and DSR-like effects
• Extended Theories of Gravity in cosmological and astrophysical applications
• Covariant single-field formulation of effective cosmological bounces