Results 81 to 90 of about 39,698 (245)

Observational Constraints on Loop Quantum Cosmology

Physical Review Letters, 2011
In the inflationary scenario of loop quantum cosmology in the presence of inverse-volume corrections, we give analytic formulas for the power spectra of scalar and tensor perturbations convenient to compare with observations. Since inverse-volume corrections can provide strong contributions to the running spectral indices, inclusion of terms higher ...
Bojowald, M., Calcagni, G., Tsujikawa, S.   +2 more
openaire   +5 more sources

Gravity Modeling of Lunar Lava Tubes: Insights From a Terrestrial Analog

Journal of Geophysical Research: Planets, Volume 130, Issue 11, November 2025.
Abstract The exploration of lunar lava tubes can address challenges of human habitation on the Moon by identifying natural shelters against radiation, temperature extremes, and micrometeoroid impacts. This study shows the feasibility of detecting lunar lava tubes with gravimetry using Ape Cave in Washington State, USA, as a terrestrial analog. Ape Cave'
Sarai Montañez Muñoz, Glyn Williams‐Jones, Nathan Hayward, Antonina Calahorrano‐Di Patre, Behraad Bahreyni   +4 more
wiley   +1 more source

Unification of Conformal and Fuzzy Gravities With Internal Interactions Resulting in SO(10) and a Possible Probe Through Stochastic Gravitational Wave Background

Fortschritte der Physik, Volume 73, Issue 9-10, October 2025.
Abstract The unification of conformal and fuzzy gravities with internal interactions is based on the facts that i) the tangent group of a curved manifold and the manifold itself do not necessarily have the same dimensions and ii) both gravitational theories considered here have been formulated in a gauge theoretic way.
Gregory Patellis, Danai Roumelioti, Stelios Stefas, George Zoupanos   +3 more
wiley   +1 more source

Variational methods in loop quantum cosmology [PDF]

Europhysics Letters (EPL), 2006
An action functional for the loop quantum cosmology difference equation is presented. It is shown that by guessing the general form of the solution and optimizing the action functional with respect to the parameters in the guessed solution one can obtain approximate solutions which are reasonably good.
Shojai, F., Shojai, A.
openaire   +3 more sources

Bounce Loop Quantum Cosmology Corrected Gauss-Bonnet Gravity

, 2015
We develop a Gauss-Bonnet extension of Loop Quantum Cosmology, by introducing holonomy corrections in modified $F(\mathcal{G})$ theories of gravity.
Haro, J., Makarenko, A. N., Myagky, A. N., Odintsov, S. D., Oikonomou, V. K.   +4 more
core   +2 more sources

A Time‐Dependent Model of the Vibrational Distribution of Nitrogen Molecules: New Rate Data Sets and Self‐Consistent Coupling With Auroral and Ionospheric Electrons

Journal of Geophysical Research: Space Physics, Volume 130, Issue 9, September 2025.
Abstract Vibrationally excited nitrogen molecules (N2) play an important role in the chemistry and dynamics of Earth's atmosphere. Electron impact, whether it originates from auroral precipitation or ionospheric thermal electrons, is among the major causes of the vibrational excitation of N2.
Jun Liang, J.‐P. St‐Maurice, E. Donovan   +2 more
wiley   +1 more source

Loop quantum cosmology scalar field models [PDF]

International Journal of Geometric Methods in Modern Physics, 2018
In this work, we use the Loop Quantum Cosmology (LQC) modified scalar–tensor reconstruction techniques in order to investigate how bouncing and inflationary cosmologies can be realized. With regard to the inflationary cosmologies, we shall be interested in realizing the intermediate inflation and the Type IV singular inflation, while with regard to ...
K. Kleidis, V. K. Oikonomou
openaire   +3 more sources

Starobinsky potential and power suppression in hybrid loop quantum cosmology

Physics Letters B
We study the effect on the primordial tensor power spectrum of varying the number of e-folds during slow-roll inflation in Loop Quantum Cosmology with a Starobinsky potential. Using the hybrid quantization approach, we derive the effective mass governing
Marceau Henry, Guillermo A. Mena Marugán, Antonio Vicente-Becerril   +2 more
doaj   +1 more source

New Hamiltonian constraint operator for loop quantum gravity

Physics Letters B, 2015
A new symmetric Hamiltonian constraint operator is proposed for loop quantum gravity, which is well defined in the Hilbert space of diffeomorphism invariant states up to non-planar vertices with valence higher than three. It inherits the advantage of the
Jinsong Yang, Yongge Ma
doaj   +1 more source

The picture of the Bianchi I model via gauge fixing in Loop Quantum Gravity

, 2012
The implications of the SU(2) gauge fixing associated with the choice of invariant triads in Loop Quantum Cosmology are discussed for a Bianchi I model.
A. Marchini, Ashtekar A., Ashtekar A., Ashtekar A., Bojowald M., Bojowald M., Bojowald M., Borja E. F., Cianfrani F., Cianfrani F. Lecian O. M. Montani G., F. Cianfrani, G. Montani, Perez A., Rovelli C., Thiemann T., Thiemann T., Thiemann T.   +16 more
core   +1 more source