--%>

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 Einstein-Podolsky-Rosen effect

    Einstein-Podolsky-Rosen effect: EPR effect: Consider the subsequent quantum mechanical thought-experiment: Take a particle that is at rest and has spun zero (0). This spontaneously decays into two fermions (spin 1/2 particles), that stream away in the

  • Q : Define Luxon Luxon : The particle that

    Luxon: The particle that travels solely at c (that is the speed of light in vacuum). All luxons have a rest mass of exactly zero. Though they are mass less, luxons do take momentum. The photons are the prime illustration of luxons (that is the name it

  • Q : Describe the term ntu in thermodynamics

    Describe the term ntu in thermodynamics? Illustrate in short.

  • Q : Define Compton Effect Compton Effect

    Compton Effect (A.H. Compton; 1923): The effect which describes those photons (that is the quantum of electromagnetic radiation) has momentum. The photon fired at a stationary particle, like an electron, will communicate momentum to t

  • Q : Fundamental principles of the regulation

    Describe the fundamental principles of the regulation? Briefly describe the principles?

  • Q : Why tea kettle sing What is the reason

    What is the reason that the tea kettle sing? Briefly state the reason.

  • Q : What is Cherenkov radiation Cherenkov

    Cherenkov radiation (P.A. Cherenkov): The radiation emitted by a huge particle which is moving faster than light in the medium via which it is travelling. No particle can travel faster than the light in vacuum, however the speed of light in other medi

  • Q : Define Sievert or SI unit of dose

    Sievert: Sv: The derived SI unit of dose equivalent, stated as the absorbed dose of the ionizing radiation multiplied by internationally-agreed-upon dimensionless weights, as various kinds of ionizing radiation cause various kinds of damage in the liv

  • Q : Define Kilogram or SI unit of mass

    Kilogram: kg: The basic SI unit of mass that is the only SI unit still maintained by a physical artifact: a platinum-iridium bar reserved in the International Bureau of Weights and Measures at Sevres, France.

  • Q : Concept of nuclear reaction Describe in

    Describe in brief the concept of nuclear reaction?