English
Related papers

Related papers: Quantum fractionary cosmology: K-essence theory

200 papers

Using the coherent-state representation we show that the classical Einstein equation for the FRW cosmological model with a general minimal scalar field can be derived from the semiclassical quantum Einstein equation.

General Relativity and Quantum Cosmology · Physics 2019-08-17 Sang Pyo Kim , Jeong-Young Ji , Hak-Soo Shin , Kwang-Sup Soh

We introduce Scale Factorized-Quantum Field Theory (SF-QFT), a framework performing path-integral factorization of ultraviolet and infrared momentum modes at a physical scale $Q^*$ before perturbative expansion through Effective Dynamical…

High Energy Physics - Phenomenology · Physics 2026-03-23 Farrukh A. Chishtie

The correct quantum description for a curvature squared term in the action can be obtained by casting the action in the canonical form with the introduction of a variable which is the negative of the first derivative of the field variable…

General Relativity and Quantum Cosmology · Physics 2008-11-26 A. K. Sanyal , B. Modak

The quantum electromagnetic (EM) field is formulated in the Weyl-Wigner representation (WW), which is equivalent to the standard Hilbert space one (HS). In principle it is possible to interpret within WW all experiments involving the EM…

General Physics · Physics 2024-12-19 Emilio Santos

We consider a time independent Schrodinger type equation derived from the equations of motion that drives a single scalar field in a standard cosmology model for inflation in a flat space-time with a Friedman-Robertson-Walker (FRW) metric…

General Relativity and Quantum Cosmology · Physics 2010-01-05 N. Barbosa-Cendejas , M. A. Reyes

Using a D = 1 supergravity framework I construct a super-Friedmann equation for an isotropic and homogenous universe including dynamical scalar fields. In the context of quantum theory this becomes an equation for a wave-function of the…

General Relativity and Quantum Cosmology · Physics 2019-02-12 J. W. van Holten

A $k$-essence scalar field model having (non canonical) Lagrangian of the form $L=-V(\phi)F(X)$ where $X=1/2g^{\mu\nu}\nabla_{\mu}\phi\nabla_{\nu}\phi$ with constant $V(\phi)$ is shown to be consistent with luminosity distance-redshift data…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-11 Abhijit Bandyopadhyay , Debashis Gangopadhyay , Arka Moulik

This is a first study of the cosmology of classical fractional gravity, a nonlocal proposal endowed with self-adjoint fractional d'Alembertian operators which serves as the basis for an ultraviolet-complete theory of quantum gravity. We…

General Relativity and Quantum Cosmology · Physics 2026-05-01 Iván Salvador-García , Gianluca Calcagni

The conventional phase space of classical physics treats space and time differently, and this difference carries over to field theories and quantum mechanics (QM). In this paper, the phase space is enhanced through two main extensions.…

Quantum Physics · Physics 2024-05-15 N. L. Diaz , J. M. Matera , R. Rossignoli

We present the case of time-varying cosmological term $\Lambda(t)$. The main idea arises by proposing that as in the cosmological constant case, the scalar potential is identified as $ V(\phi)=2\Lambda$, with $\Lambda$ a constant, this…

General Physics · Physics 2019-11-21 J. Socorro , M. D'oleire , Luis O. Pimentel

We derive the primordial power spectrum of density fluctuations in the framework of quantum cosmology. For this purpose we perform a Born-Oppenheimer approximation to the Wheeler-DeWitt equation for an inflationary universe with a scalar…

General Relativity and Quantum Cosmology · Physics 2012-01-17 Claus Kiefer , Manuel Kraemer

We develop a quantum effective action for scalar-tensor theories of gravity which is both spacetime diffeomorphism invariant and field reparameterisation (frame) invariant beyond the classical approximation. We achieve this by extending the…

High Energy Physics - Theory · Physics 2020-08-26 Kieran Finn , Sotirios Karamitsos , Apostolos Pilaftsis

We investigate the thermodynamic and phenomenological implications of a cosmological model governed by fractional entropy applied to the apparent horizon of a flat Friedmann-Lema\^{i}tre-Robertson-Walker (FLRW) universe. By utilizing the…

General Relativity and Quantum Cosmology · Physics 2026-04-21 Miguel Cruz , Diego da Silva , Simón González , Samuel Lepe , Joel Saavedra , Manuel Gonzalez-Espinoza

We apply the de Broglie-Bohm interpretation to the Wheeler-DeWitt equation for the quantum FRW cosmological model with a minimal massless scalar field. We find that the quantum FRW cosmological model has quantum potential dominated…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Sang Pyo Kim

It is well known that in quantum gravity, the very geometry of space and time is subject to continual fluctuation. The mathematical formulation for this old theory is still lacking. This article formulates this more than forty-year-old…

General Relativity and Quantum Cosmology · Physics 2024-09-27 Behzad Tajahmad

This article presents numerical work on a special case of the cosmological semiclassical Einstein equation (SCE). The SCE describes the interaction of relativistic quantum matter by the expected value of the renormalized stress-energy…

General Relativity and Quantum Cosmology · Physics 2022-06-17 Hanno Gottschalk , Nicolai Rothe , Daniel Siemssen

We show that Einstein's field equations for spatially flat Friedmann-Robertson-Walker (FRW) space times have a form invariance symmetry (FIS) realized by the form invariance transformations (FIT) which are indeed generated by an invertible…

General Relativity and Quantum Cosmology · Physics 2013-04-01 Luis P. Chimento , Martín G. Richarte , Iván E. Sánchez G

The light-front Hamiltonian formulation for the scalar field theory contains a new ingredient in the form of a constraint equation. Renormalization of the two dimensional $\phi^{4}$ theory, described in the continuum, is discussed. The mass…

High Energy Physics - Theory · Physics 2007-05-23 Prem P. Srivastava

In the present work, we study the quantum cosmology description of closed Friedmann-Robertson-Walker models in the presence of a positive cosmological constant and a generic perfect fluid. We work in the Schutz's variational formalism. If…

General Relativity and Quantum Cosmology · Physics 2009-09-02 E. V. Corrêa Silva , G. A. Monerat , G. Oliveira-Neto , C. Neves , L. G. Ferreira Filho

The Universe is homogeneous and isotropic on large scales, so on those scales it is usually modelled as a Friedmann-Lema\^{i}tre-Robertson-Walker (FLRW) space-time. The non-linearity of the Einstein field equations raises concern over…

General Relativity and Quantum Cosmology · Physics 2021-03-03 Yonadav Barry Ginat