Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Cosmology, Relativity, and Gravity

Embry-Riddle Aeronautical University

Hubble parameter

Articles 1 - 2 of 2

Full-Text Articles in Physical Sciences and Mathematics

Hubble Parameter Measurement Constraints On The Redshift Of The Deceleration-Acceleration Transition, Dynamical Dark Energy, And Space Curvature, Muhammad O. Farooq, Foram R. Madiyar, Sara Crandall, Bharat Ratra Jan 2017

Hubble Parameter Measurement Constraints On The Redshift Of The Deceleration-Acceleration Transition, Dynamical Dark Energy, And Space Curvature, Muhammad O. Farooq, Foram R. Madiyar, Sara Crandall, Bharat Ratra

Publications

We compile an updated list of 38 measurements of the Hubble parameter H(z) between redshifts 0.07 ≤ z ≤ 2.36 and use them to place constraints on model parameters of constant and time-varying dark energy cosmological models, both spatially flat and curved. We use five models to measure the redshift of the cosmological deceleration-acceleration transition, zda, from these H(z) data. Within the error bars, the measured zda are insensitive to the model used, depending only on the value assumed for the Hubble constant H0. The weighted mean of our measurements is zda = 0.72 ± 0.05 (0.84 ± 0.03) for …


Using Hubble Parameter Measurements To Find Constraints On Dark Energy Based On Different Cosmological Models, William Wilson, Muhammad O. Farooq Jan 2017

Using Hubble Parameter Measurements To Find Constraints On Dark Energy Based On Different Cosmological Models, William Wilson, Muhammad O. Farooq

Student Works

In this paper, Hubble parameter versus redshift data, collected from multiple resources, is used to place constraints on the parameters of two current Cosmological dark energy models. The first dark energy model considered is the Standard Model of cosmology, also known as ΛCDM with spatial curvature, which is primarily based on Einstein’s General Theory of Relativity with a spatially homogeneous time-independent cosmological constant, Λ. The second is the XCDM model which parameterize dark energy as a fluid whose density can vary with time. The H(z) data collected through different experimental sources was used to put constraints on the parameters of …