The Hubble constant, which measures the expansion rate, together with the total energy density of the Universe, sets the size of the observable Universe, its age, and its radius of curvature. Excellent progress has been made recently toward the measurement of the Hubble constant: a number of ...
The Hubble constant is the constant of proportionality between recession velocity and distance in the expanding universe. It is a fundamental property of cosmology that sets both the scale and the expansion age of the universe. It is determined by measurement of galaxy radial velocities and distances...
Hubble constant,Hubble parameter,Hubble's parameter cosmogeny,cosmogony,cosmology- the branch of astrophysics that studies the origin and evolution and structure of the universe constant- a number representing a quantity assumed to have a fixed value in a specified mathematical context; "the velocity ...
For the quadruple gravitational lens PG 1115 + 080, we combine recent measurements of the time delays with new lens models to determine the Hubble constant H_0. We explore the effects of systematic uncertainties in the lens models on the estimates of H_0, and we discuss how the uncertainties...
The Hubble constant. (cover story)Examines current determinations of the Hubble constant, a fundamental property of cosmology that sets both the scale and the expansion age of the universe. Description of the Hubble constant; How it is determined; Use in measurement of galaxy distances; Calibration...
We consider a k-essence scalar field model for the late-time cosmic acceleration in which the sound speed, parametrized as $$c_s$$ is constant. We compute
Time Delay in Gravitational Lenses: an Alternative Route to the Hubble Constant between these different images can lead to a determination of distances between the source, the lens and the observer and, thus, of the Hubble constant... P Magain - 《Journal of Pharmacology & Experimental Therapeut...
The Hubble Constant is the unit of measurement used to describe the expansion of the universe. The cosmos has been getting bigger since the Big Bang kick-started the growth about 13.82 billion years ago. The universe, in fact, is getting faster in its acceleration as it gets bigger. What'...
The apparent cosmological conflict between the age of the Universe, predicted in the standard Friedman cosmology by using the recent measurement of the larger Hubble constant from a direct calibration of the distance to the Virgo galaxy cluster, and the ages of the oldest stars and globular cluster...
<italic>Context.</italic> The precise determination of the present-day expansion rate of the Universe, expressed through the Hubble constant <italic>H</italic>0, is one of the most pressing challenges in modern cosmology. Assuming flat ΛCDM,