The Cosmological Constant :
To derive his 1917 cosmological model, Einstein made three assumptions that lay outside the scope of his equations. The first was to suppose that the universe is homogeneous and isotropic in the large (i.e.
cosmological constant; Lambda
The constant introduced to the Einstein field equation, intended to admit static cosmological solutions.
cosmological constant
a term in the equations of general relativity that represents a repulsive force in the universe
cosmology ...
Cosmological Constant- a mathematical device used by Einstein to give space-time an inbuilt tendency to expand
Cosmology- the study of the universe as a whole ...
cosmological constant: Einstein's constant that represents a repulsion in space to oppose gravity.
cosmological principle: The assumption that any observer in any galaxy sees the same general features of the universe.
COSMOLOGICAL CONSTANT (Λ) - Constant introduced by Einstein in 1917 to reconcile his theory of General Relativity with the prevailing assumption that the universe was static, later interpreted as the energy density of the vacuum.
Cosmological Constant
(a) A term added by Einstein to the gravitational field equations of his theory of general relativity.
The Cosmological Constant
Albert Einstein completed his theory of General Relativity in 1915. When he applied his theory to the spacetime of the universe, he found that gravity would not permit the universe to be static.
see Cosmological Constant [LB90]
Lambert's Law
(a) First proposed in 1760; then restricted to visible light, it is now used with all radiations. The law concerns the rate of absorption of radiation as it travels deeper into a medium.
cosmological constant
The expansion of the universe is speeding up
cosmological inflation ...
Cosmological Constant Wikipedia
In physical cosmology, the cosmological constant (usually denoted by the Greek capital letter lambda) was proposed by Albert Einstein as a modification of his original theory of general relativity to achieve a ...
cosmological constant; Lambda
A constant term (labeled Lambda) which Einstein added to his general theory of relativity in the mistaken belief that the Universe was neither expanding nor contracting.
cosmological constant - (n.)
A term added to the field equations by Einstein in order to allow solutions in which the universe was static; that is, neither expanding nor contracting.
The cosmological constant has negative pressure equal to its energy density and so causes the expansion of the universe to accelerate (see equation of state (cosmology)).
INTERLUDE 27-1 The Cosmological Constant
Even the greatest minds are fallible. The first scientist to apply general relativity to the universe was, not surprisingly, the theory's inventor, Albert Einstein.
* 1917 - Willem de Sitter derives an isotropic static cosmology with a cosmological constant as well as an empty expanding cosmology with a cosmological constant, termed a de Sitter universe ...
The findings are consistent with the idea of dark energy behaving like Albert Einstein's cosmological constant. The cosmological constant describes the idea that there is a density and pressure associated with "empty" space.
In the early part of the 20th century Albert Einstein had invoked a 'cosmological constant', (usually symbolized by the Greek letter lambda, Λ).
Yes, the genius was so intent at getting what he thought was the right answer that he sort of fudged the formula by adding an extra term to it, what is called the Cosmological Constant. It is usually represented by the Greek letter .
To make his equations fit these assumptions, Einstein added a "cosmological constant" whose effect was repulsive.
The dark energy density is the energy of the vacuum, which is also called the cosmological constant. Although we can measure it, we do not know much about it. There is a value called the critical density.
Big news has been the finding that high-redshift type Ia supernovae show evidence of upward curvature in the analogous magnitude-redshift relation, implying a nonzero cosmological constant.
So Einstein added to his equations what he called a "cosmological constant," a term that accounted for whatever force was supposedly keeping the universe static.
Einstein correspondingly modified his field equation. See Cosmological constant
Hypothesis about the abundance of the elements ...
See also: Primordial fluctuations, Cosmological constant, and Lambda-CDM model ...
If the Universe has a very low density of matter, then its extrapolated age is larger, 1/H0. If the theory of General Relativity is modified to include a cosmological constant, then the inferred age can be even larger.
This introduced a "cosmological constant" in his equations, resulting in a static universe. He therefore missed a chance to predict the expansion of the universe by introducing an arbitrary constant.
Determining the strength of dark energy, and whether it varies over time, is crucial for the task of nailing down which theory of dark energy - be it the cosmological constant, quintessence or something else - is correct.
 See also: Universe, Time, Energy, Light, Galaxies
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