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We elaborate on the proposal of [Phys. Rev. Lett. 123 (2019) 13, 131302], about the possibility of hiding the cosmological constant in the complicated topology that one expects to exist at the Planck scale. We build a differential equation…

General Relativity and Quantum Cosmology · Physics 2020-11-25 Oliver F. Piattella

It is shown that in the theory of discrete quantum gravity the cosmological constant problem can be solved due to the phenomena of elliptic operators spectrum "loosening" and universe inflation.

High Energy Physics - Theory · Physics 2007-05-23 S. N. Vergeles

This paper investigates a scale-invariant inflationary model characterized by a scalar field non-minimally coupled to gravity and a curvature term quadratic in the Ricci scalar. The model's dynamic is analyzed using a full numerical…

High Energy Physics - Theory · Physics 2024-10-10 Mariaveronica De Angelis , Chiara Cecchini , Massimiliano Rinaldi

A simple model is introduced in which the cosmological constant is interpreted as a true Casimir effect on a scalar field filling the universe (e.g. $\mathbf{R} \times \mathbf{T}^p\times \mathbf{T}^q$, $\mathbf{R} \times \mathbf{T}^p\times…

High Energy Physics - Theory · Physics 2009-10-31 E. Elizalde

We consider approaches to cosmological parameter estimation in the inflationary cosmology, focussing on the required accuracy of the initial power spectra. Parametrizing the spectra, for example by power-laws, is well suited to testing the…

Astrophysics · Physics 2009-11-07 Samuel M. Leach , Andrew R. Liddle , Jerome Martin , Dominik J. Schwarz

We propose a natural solution to the cosmological constant problem consistent with the standard cosmology and successful over a broad range of energies. This solution is based on the existence of a new field, the devaluton, with its…

High Energy Physics - Phenomenology · Physics 2009-11-11 Katherine Freese , James T. Liu , Douglas Spolyar

In a previous paper we proposed a new approach to the beginning of inflation -- a lingering universe. The universe begins in a lingering state with a nearly vanishing Hubble parameter. This calls into question the absolute age of the…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-09 Brandon Melcher , Arnab Pradhan , Scott Watson

This paper discusses the problem of inflation in the context of Friedmann-Robertson-Walker Cosmology. We show how, after a simple change of variables, to quantize the problem in a way which parallels the classical discussion. The result is…

High Energy Physics - Theory · Physics 2007-05-23 Marvin Weinstein , Ratindranath Akhoury

The accelerating expansion of the Universe points to a small positive value for the cosmological constant or vacuum energy density. We discuss recent ideas that the cosmological constant plus LHC results might hint at critical phenomena…

High Energy Physics - Phenomenology · Physics 2015-07-09 Steven D. Bass

A new vision of the beginning and expansion of our universe has produced a solution to the vacuum energy problem (also known as "cosmological constant problem"). A new dynamic of cellular spaces and a discrete time has space being produced…

Astrophysics · Physics 2007-05-23 Charles B. Leffert

The possibility of extending the quantum mechanical superposition principle to free parameters such as the cosmological constant appearing in the Lagrangian of physical theories is examined. If the cosmological constant is subject to a…

General Relativity and Quantum Cosmology · Physics 2017-12-15 Josily Cyriac

Loop quantum cosmology is considered in inflation era. A slow roll scalar field solution with power law potential is presented in the neighborhood of transition time, i.e. when the universe enters inflation phase from super-inflation. The…

General Relativity and Quantum Cosmology · Physics 2017-03-08 H. Mohseni Sadjadi

The cosmological constant problem is studied in a two component cosmological model. The universe contains a cosmological constant of an arbitrary size and sign and an additional component with an inhomogeneous equation of state. It is shown…

General Relativity and Quantum Cosmology · Physics 2009-01-16 Hrvoje Stefancic

The standard model of cosmology is investigated using time dependent cosmological constant $\Lambda$ and Newton's gravitational constant $G$. The total energy content is described by the modified Chaplygin gas equation of state. It is found…

General Relativity and Quantum Cosmology · Physics 2009-03-12 Mubasher Jamil , Farook Rahaman , Mehedi Kalam

We propose a mechanism for generating an inflationary phase in the early universe without resorting to any type of scalar field(s). Instead, this accelerated expansion is driven by a dynamical "cosmological constant" in the framework of…

General Relativity and Quantum Cosmology · Physics 2022-03-18 Gabriel Leon

We propose a scenario of the beginning of inflation in which the non-vacuum value of the scalar field that drives inflation develops dynamically due to the non-minimal coupling to gravity. In this scenario, inflation emerges as an…

High Energy Physics - Phenomenology · Physics 2016-09-06 M. V. Libanov , V. A. Rubakov , P. G. Tinyakov

Recent Planck data show the anomalies of CMB fluctuations on large angular scales, which confirms the early observations by WMAP. We continue studying an inflationary model, in which before the slow roll inflation the universe is in a…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-15 Zhi-Guo Liu , Zong-Kuan Guo , Yun-Song Piao

Several attempts to solve the cosmological constant problem, which concerns the value of the cosmological constant being extremely smaller than the Standard Model mass scales, have introduced a scalar field with a very flat potential that…

High Energy Physics - Phenomenology · Physics 2024-04-10 Wen Yin

Cosmological data suggest that we live in an interesting period in the history of the universe when \rho_\Lambda \sim \rho_M \sim \rho_R. The occurence of any epoch with such a "triple coincidence" is puzzling, while the question of why we…

Astrophysics · Physics 2009-09-29 Nima Arkani-Hamed , Lawrence J. Hall , Christopher Kolda , Hitoshi Murayama

We analyze cosmological perturbations to the linear order in the context of inflation with an arbitrary number of scalar fields. The fields take values on a non-trivial manifold with a positive-definite metric and are non-minimally coupled…

Astrophysics · Physics 2007-05-23 Joydev Lahiri , Gautam Bhattacharya