Time Dependent Gravitational Constant in Chern Simons Modified Gravity
نویسندگان
چکیده
Two dark energy models $Lambda sim (frac{dot{a}}{a})^{2}$ and frac{ddot{a}}{a}$ are studied by taking into account the gravitational constant G is a time-dependent parameter in framework of Chern-Simons modified gravity. It found that shown increasing behavior proportional to those time for each model. These compared with observational results regulating values parameters. Our investigations indicated model generally attractive nature while other coincides repulsive situation consequently match current scenario accelerating universe. We calculated variation G(t) which showed it changes rapidly when value $omega$ taken between limit $-1.33 <omega< -0.79 $. viewed due composite influence time-variable $Lambda$ G(t), universe expanded acceleration. Further, estimated range proper tuning parameters $alpha$ $beta$ given as $-(1.89pm 0.10)times 10^{-11}yr^{-1}<frac{dot{G}}{G}<0$ Ia type supernova.
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ژورنال
عنوان ژورنال: Iranian Journal of Physics Research
سال: 2022
ISSN: ['2345-3664', '1682-6957']
DOI: https://doi.org/10.47176/ijpr.21.3.41049