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We propose a novel extension to the recently developed non-commutative Riemannian foliated branch-cut quantum gravity (BCQG). Based on an extended Faddeev-Jackiw symplectic deformation of the conventional Poisson algebra, we investigate…

A general equation, describing the lowest order corrections coming from quantum gravitational effects to the spectrum of cosmological scalar fluctuations is obtained. These corrections are explicitly estimated for the case of a de Sitter…

General Relativity and Quantum Cosmology · Physics 2015-06-16 Alexander Y. Kamenshchik , Alessandro Tronconi , Giovanni Venturi

We investigate the dynamics of super-inflation in two versions of Loop Quantum Cosmology, one in which the Friedmann equation is modified by the presence of inverse volume corrections, and one in which quadratic corrections are important.…

General Relativity and Quantum Cosmology · Physics 2008-11-26 E. J. Copeland , D. J. Mulryne , N. J. Nunes , M. Shaeri

Recently, the Planck 2013 results showed possible evidence for a dipolar power modulation of the CMB temperature fluctuations at low--(\ell) multipoles. This anomaly might imply certain deviations from statistical isotropy. To incorporate…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-24 Zhe Chang , Sai Wang

We evaluate the Lorentzian gravitational path integral in the presence of non-vanishing torsion with the application of the Picard-Lefschetz theory for minisuperspaces corresponding to a number of phenomenological bouncing cosmological…

General Relativity and Quantum Cosmology · Physics 2024-04-15 Vikramaditya Mondal , Sumanta Chakraborty

We consider curved space quantum corrections to the equations of motion of the inflaton field in the early Universe. Using the stochastic formalism in phase space, we demonstrate that the quantum corrected evolution of the inflaton can…

High Energy Physics - Phenomenology · Physics 2009-09-25 Zygmunt Lalak , Rudolf Poppe

We present uniform rate inflation in a modified $f(T, \mathcal{T}) $ gravity. It is found that early inflation can be realized even with a scalar field field with a quadratic potential and a negative cosmological constant. We construct…

General Relativity and Quantum Cosmology · Physics 2025-07-02 Priyanka Mandal , B. C. Paul

We reconsider the fine-tuning problem of scalar-driven inflation arising from the need to couple the inflaton to ordinary matter in order to make reheating efficient. Quantum fluctuations of this matter induce Coleman-Weinberg corrections…

General Relativity and Quantum Cosmology · Physics 2019-11-13 S. P. Miao , S. Park , R. P. Woodard

We consider a noncommutative (NC) inflationary model with a homogeneous scalar field minimally coupled to gravity. The particular NC inflationary setting produces entirely new consequences. We first analyze the free field case and…

General Relativity and Quantum Cosmology · Physics 2018-05-01 S. M. M. Rasouli , N. Saba , M. Farhoudi , J. Marto , P. Moniz

We perform a minisuperspace analysis of an information-theoretic nonlinear Wheeler-deWitt (WDW) equation for de Sitter universes. The nonlinear WDW equation, which is in the form of a difference-differential equation, is transformed into a…

General Relativity and Quantum Cosmology · Physics 2012-04-02 Rajesh R. Parwani , Siti Nursaba Tarih

One of the most important achievements of inflationary cosmology is to predict a departure from scale invariance of the power spectrum for scalar curvature cosmological fluctuations. This tilt is understood as a consequence of a quasi de…

High Energy Physics - Theory · Physics 2021-10-25 Cesar Gomez , Raul Jimenez

We show that a contracting universe which bounces due to quantum cosmological effects and connects to the hot big-bang expansion phase, can produce an almost scale invariant spectrum of perturbations provided the perturbations are produced…

High Energy Physics - Theory · Physics 2008-11-26 Patrick Peter , E. J. C. Pinho , Nelson Pinto-Neto

In the case of a spatially flat Friedmann--Lema\^{\i}tre--Robertson--Walker universe in $f\left( R\right) $-gravity we write the Wheeler-DeWitt equation of quantum cosmology. The equation depends on the functional form of $f\left( R\right)…

General Relativity and Quantum Cosmology · Physics 2020-01-17 Andronikos Paliathanasis

We describe the universe as a local, inhomogeneous spherical bubble embedded in a flat matter dominated FLRW universe. Generalized exact Friedmann equations describe the expansion of the universe and an early universe inflationary de Sitter…

Astrophysics · Physics 2007-05-23 J. W. Moffat

We derive the first quantum gravitational corrections to the inflationary power spectra for a general single-field scalar-tensor theory which includes a non-minimal coupling to gravity, a non-standard scalar kinetic term and an arbitrary…

General Relativity and Quantum Cosmology · Physics 2020-01-08 Christian F. Steinwachs , Matthijs L. van der Wild

We investigate the possible effect of cosmological-constant type dark energy during the inflation period of the early universe. This is accommodated by a new dispersion relation in de Sitter space. The modified inflation model of a…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Zhe Chang , Ming-Hua Li , Sai Wang , Xin Li

According to the `Cosmological Central Dogma', de Sitter space can be viewed as a quantum mechanical system with a finite number of degrees of freedom, set by the horizon area. We use this assumption together with the Wheeler-DeWitt (WDW)…

High Energy Physics - Theory · Physics 2025-12-01 Bjoern Hassfeld , Arthur Hebecker , Manfred Salmhofer , Jonah Cedric Strauss , Johannes Walcher

Recent and upcoming experimental data as well as the possibility of rich phenomenology has spiked interest in studying the quantum gravitational effects in cosmology at low (inflation-era) energy scales. While Planck scale physics is under…

General Relativity and Quantum Cosmology · Physics 2019-05-30 Sandeep Aashish , Sukanta Panda

We establish a general thermodynamic scheme for cosmic fluids with internal self-interactions and discuss equilibrium and non-equilibrium aspects of such systems in connection with (generalized) symmetry properties of the cosmological…

Astrophysics · Physics 2009-10-31 Winfried Zimdahl , Alexander B. Balakin

The Wheeler-DeWitt equation is solved for the Bergmann-Wagoner scalar-tensor gravitational theory in the case of Friedmann-Robertson- Walker cosmological model. We present solutions for several cosmological functions: i) \lambda(\phi)=0,…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Luis O. Pimentel , Cesar Mora