Search results
Results From The WOW.Com Content Network
The density parameter is the average density of the universe divided by the critical energy density, that is, the mass energy needed for a universe to be flat. Put another way, If Ω = 1, the universe is flat. If Ω > 1, there is positive curvature. If Ω < 1, there is negative curvature.
The local geometry of the universe is determined by whether the relative density Ω is less than, equal to or greater than 1. From top to bottom: a spherical universe with greater than critical density (Ω>1, k>0); a hyperbolic, underdense universe (Ω<1, k<0); and a flat universe with exactly the critical density (Ω=1, k=0). The spacetime of ...
The geometry of spacetime has been measured by the Wilkinson Microwave Anisotropy Probe (WMAP) to be nearly flat. According to the WMAP 5-year results and analysis, “WMAP determined that the universe is flat, from which it follows that the mean energy density in the universe is equal to the critical density (within a 1%
The fraction of the total energy density of our (flat or almost flat) universe that is dark energy, , is estimated to be 0.669 ± 0.038 based on the 2018 Dark Energy Survey results using Type Ia supernovae [8] or 0.6847 ± 0.0073 based on the 2018 release of Planck satellite data, or more than 68.3 % (2018 estimate) of the mass–energy density ...
The portion of the universe that can be seen by humans is approximately 93 billion light-years in diameter at present, but the total size of the universe is not known. [3] Some of the earliest cosmological models of the universe were developed by ancient Greek and Indian philosophers and were geocentric, placing Earth at the center.
Black-hole cosmology is a cosmological model in which the observable universe is the interior of a black hole existing as one of possibly many universes inside a larger universe. [89] This includes the theory of white holes , which are on the opposite side of space-time .
Parks became one of the most impactful Black women in American history almost overnight when she refused to move to the “colored” section of a public bus in 1955. This act of protest kicked ...
The Flat Earth model is a belief that the Earth's shape is a plane or disk covered by a firmament containing heavenly bodies. Most pre-scientific cultures have had conceptions of a Flat Earth, including Greece until the classical period , the Bronze Age and Iron Age civilizations of the Near East until the Hellenistic period , India until the ...