Search results
Results from the WOW.Com Content Network
A graphical representation of the expansion of the universe from the Big Bang to the present day, with the inflationary epoch represented as the dramatic expansion seen on the left. This visualization shows only a section of the universe; the empty space outside the diagram should not be taken to represent empty space outside the universe ...
The accelerated expansion of the universe is thought to have begun since the universe entered its dark-energy-dominated era roughly 5 billion years ago. [ 8 ] [ notes 1 ] Within the framework of general relativity , an accelerated expansion can be accounted for by a positive value of the cosmological constant Λ , equivalent to the presence of ...
Timeline of the expansion of the universe, where space, including hypothetical non-observable portions of the universe, is represented at each time by the circular sections. On the left, the dramatic expansion occurs in the inflationary epoch ; and at the center, the expansion accelerates (artist's concept; neither time nor size are to scale).
The second equation states that both the energy density and the pressure cause the expansion rate of the universe ˙ to decrease, i.e., both cause a deceleration in the expansion of the universe. This is a consequence of gravitation , with pressure playing a similar role to that of energy (or mass) density, according to the principles of ...
If dark energy—represented by the cosmological constant, a constant energy density filling space homogeneously, [3] or scalar fields, such as quintessence or moduli, dynamic quantities whose energy density can vary in time and space—accelerates the expansion of the universe, then the space between clusters of galaxies will grow at an ...
In physical cosmology, cosmic inflation, cosmological inflation, or just inflation, is a theory of exponential expansion of space in the very early universe.Following the inflationary period, the universe continued to expand, but at a slower rate.
Vacuum state is a configuration of quantum fields representing a local minimum (but not necessarily a global minimum) of energy. Inflationary models propose that at approximately 10-36 seconds after the Big Bang, vacuum state of the Universe was different from the one seen at the present time: the inflationary vacuum had a much higher energy density.
The term outward space existed in a poem from 1842 by the English poet Lady Emmeline Stuart-Wortley called "The Maiden of Moscow", [13] but in astronomy the term outer space found its application for the first time in 1845 by Alexander von Humboldt. [14] The term was eventually popularized through the writings of H. G. Wells after 1901. [15]