--%>

Explain Cosmological constant

Cosmological constant (Lambda): The constant mentioned to the Einstein field equation, proposed to admit the static cosmological solutions. At the time the present philosophical view was steady-state model of the space, where the Universe has been around for unlimited time. Prior analysis of the field equation pointed that the general relativity permitted dynamic cosmological models only (ones which are either contracting or expanding), however no static models. Einstein mentioned the most natural aberration to the field equation which he could think of: the addition of a term proportional to the space time metric tensor, g, with constant of proportionality being the cosmological constant as:

G + Lambda g = 8 pi T.

Hubble's afterward discovery of the expansion of the Universe pointed that the introduction of the cosmological constant was needless; had Einstein believed what his field equation was stating him, he could have declared the expansion of the Universe as perhaps the supreme and most convincing prediction of general relativity; he termed this the "greatest blunder of my life."

   Related Questions in Physics

  • Q : Define Ergosphere Ergosphere: The area

    Ergosphere: The area around a rotating black hole, among the event horizon and the static limit, where the rotational energy can be removed from the black hole.

  • Q : Define Coulomb or SI unit of electric

    Coulomb: C (after C. de Coulomb, 1736-1806): The derived SI unit of an electric charge, stated as the quantity of charge shifted by a current of 1 A in a period of 1 s; it therefore has units of A s.

  • Q : Fission and Fusion What do you mean by

    What do you mean by Fission and Fusion?

  • Q : What do you mean by the term nucleus

    What do you mean by the term nucleus? Describe in brief.

  • Q : What do you mean by the term cardiac

    What do you mean by the term cardiac output? Briefly explain it.

  • Q : Define Siemens or SI unit of an

    Siemens: S (after E.W. von Siemens, 1816-1892): The derived SI unit of an electrical conductance equivalent to the conductance of an element which has a resistance of 1 O [ohm]; this has units of O-1.

  • Q : Define Systeme Internationale d'Unites

    Systeme Internationale d'Unites (SI): The rationalized and coherent system of units derived from the m.k.s. system (that itself is derived from metric system) in common utilization in physics nowadays.

  • Q : Define Planck constant Planck constant

    Planck constant: h: The basic constant equivalent to the ratio of the energy of a quantum of energy to its frequency. This is the quantum of action. This has the value 6.626 196 x 10-34 J s.

  • Q : Explain Youngs experiment or

    Young's experiment: double-slit experiment (T. Young; 1801): A well-known experiment that exhibits the wave nature of light (and certainly of other particles). The light is passed from a small source into an opaque screen with the two thin slits. The

  • Q : Define Watt or SI unit of power Watt: W

    Watt: W (after J. Watt, 1736-1819): The derived SI unit of power, stated as a power of 1 J acting over the period of 1 s; it therefore has the units of J/s.