Results 41 to 50 of about 6,968,010 (306)

Cosmological models with a Hybrid Scale Factor [PDF]

, 2021
In this brief review, we present some cosmological models with a Hybrid Scale Factor (HSF) in the framework of general relativity (GR). The hybrid scale factor fosters an early deceleration as well as a late time acceleration and mimics the present ...
Tripathy, S.K., Ray, Saibal, Mishra, B., Tripathy, S. K., Khlopov, Maxim, B. Mishra, S. K. Tripathy, Maxim Khlopov, Saibal Ray   +8 more
core   +1 more source

Stability of Einstein-Aether Cosmological Models [PDF]

, 2013
We use a dynamical systems analysis to investigate the future behaviour of Einstein-Aether cosmological models with a scalar field coupling to the expansion of the aether and a non-interacting perfect fluid. The stability of the equilibrium solutions are
Coley, Alan, Alhulaimi, B., Sandin, Patrik, Sandin, P., Coley, A., Alhulaimi, Bassemah, Coley, Alan,, Alhulaimi, Bassemah,, Sandin, Patrik,   +8 more
core   +1 more source

Programmable Sequential 4D Actuation in Multistable Kirigami Metamaterials

Advanced Science, EarlyView.
This study presents a modular kirigami metamaterial framework enabling programmable multistability and sequential 4D actuation. By coupling geometry‐controlled multistability with material‐dependent recovery kinetics, spatiotemporal deformation can be precisely programmed.
Eui‐Hyun Kim, Minsung Kim, Hyunsik Yoon, Keun Park   +3 more
wiley   +1 more source

Jordan frame in supergravity and cosmology

Journal of High Energy Physics
The superconformal action can be gauge-fixed in a gauge where it leads to the Einstein frame supergravity defined by a Kähler potential K z z ¯ $$ \mathcal{K}\left(z,\overline{z}\right) $$ , or in a gauge where it leads to a Jordan frame supergravity ...
Renata Kallosh
doaj   +1 more source

Polynomial Affine Model of Gravity: After 10 Years

Universe
The polynomial affine model of gravity was proposed as an alternative to metric and metric-affine gravitational models. What, in the beginning, was thought to be a source of unpredictability—the presence of many terms in the action—turned out to be a ...
Oscar Castillo-Felisola, Bastian Grez, Manuel Morocho-López, Jose Perdiguero, Aureliano Skirzewski, Jefferson Vaca-Santana, Nicolas Zambra-Gómez   +6 more
doaj   +1 more source

The morphology of the oval window in Paranthropus robustus compared to humans and other modern primates

The Anatomical Record, EarlyView.
Abstract The oval window (OW) is an opening connecting the inner and middle ear. Its area has been shown to consistently scale with body mass (BM) in primates, and has been used alongside semi‐circular canal (SCC) size to differentiate Homo sapiens and fossil hominins, including Paranthropus robustus.
Ruy Fernandez, José Braga
wiley   +1 more source

The BINGO/ABDUS Project: Forecast for Cosmological Parameters from a Mock Fast Radio Burst Survey

The Astrophysical Journal
There are various surveys that will provide excellent data to search for and localize fast radio bursts (FRBs). The BINGO project will be one such survey, and this collaboration has already estimated an FRB detection rate that the project will yield.
Xue Zhang, Yu Sang, Gabriel A. Hoerning, Filipe B. Abdalla, Elcio Abdalla, Amilcar Queiroz, André A. Costa, Ricardo G. Landim, Chang Feng, Bin Wang, Marcelo V. dos Santos, Thyrso Villela, Carlos A. Wuensche, Jiajun Zhang, Edmar C. Gurjão, Alessandro Marins, Alexandre J. R. Serres, Linfeng Xiao   +17 more
doaj   +1 more source

A Critique of Cosmological Natural Selection [PDF]

, 2004
Mathematical physicist Lee Smolin has proposed a theory of Cosmological natural selection which, he argues, explains the existence of our life-supporting universe, and which, he claims, is superior to Anthropic Principle explanations.
McCabe, Gordon, Gordon Mccabe
core  

Direct SMBH Formation Driven by Runaway Stellar Collisions in Globally Unstable Stellar Systems

Astronomische Nachrichten, EarlyView.
ABSTRACT The fueling problem addresses the ultimate fate of the reservoirs of gas and stars driven into the deepest gravitational potential wells of galaxies, thus it may contain the Universe's densest concentrations of gas and stars. This raises a key question: does the infalling material collapse directly into a supermassive black hole, or can it ...
Marcelo C. Vergara, Andrés Escala
wiley   +1 more source

Cosmological Implications of the Extended Uncertainty Principle: Energy Conditions, Stability, and Late-time Acceleration

The Astrophysical Journal
We study the cosmological consequences of the extended uncertainty principle (EUP) by deriving modified Friedmann equations through thermodynamic arguments.
M. Roushan, N. Rashidi
doaj   +1 more source