Cosmological perturbations with inverse-volume corrections in loop quantum cosmology
arXiv:1809.00313 · doi:10.1103/PhysRevD.98.083507
Abstract
Although the cosmological perturbations with inverse-volume corrections from loop quantum cosmology have been studied using the anomaly-free algebra approach in much of the literature, there still remains an important issue that some counterterms in the perturbed constraints cannot be uniquely fixed on the spatially flat Friedmann-Robterson-Walker background, which causes ambiguities in the perturbation equations. In this paper, we show that this problem can be overcome by extending the anomaly-free algebra to the spatially closed Friedmann-Robterson-Walker background. We find that a consistent deformed algebra can be obtained in the spatially closed case, and each counter term can be uniquely fixed in terms of the inverse-volume correction functions; then, by taking the large limit, we recover the anomaly-free Hamiltonian on the spatially flat background. Using this Hamiltonian we obtain the gauge invariant cosmological perturbations for scalar, vector and tensor modes in the spatially flat case. Moreover, we also derive the quantum-corrected Mukhanov equations, from which the scalar and tensor spectral indices with inverse-volume corrections are given. Some key cosmological perturbation equations obtained in this paper are different from those in previous literature.
16 pages, no figures, presentation improved
References in corpus (12)
- Loop quantum cosmology of k=1 FRW models
- Anomaly freedom in perturbative loop quantum gravity
- Closed FRW model in Loop Quantum Cosmology
- Loop quantum gravity corrections to gravitational wave dispersion
- Hybrid Quantum Gowdy Cosmology: Combining Loop and Fock Quantizations
- Consistency of holonomy-corrected scalar, vector and tensor perturbations in Loop Quantum Cosmology
- Gauge invariant cosmological perturbation equations with corrections from loop quantum gravity
- Inhomogeneous Loop Quantum Cosmology: Hybrid Quantization of the Gowdy Model
- Anomaly-free cosmological perturbations in effective canonical quantum gravity
- Cosmological vector modes and quantum gravity effects
- Inflationary observables in loop quantum cosmology
- Anomaly free cosmological perturbations with generalised holonomy correction in loop quantum cosmology