--%>
Assignment Help - homework help

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 : What is Speed of light Speed of light

    Speed of light (in vacuo): c: The speed at which the electromagnetic radiation spreads in a vacuum; it is stated as 299 792 458 m/s.

    		•
  • Q : Define Pauli Exclusion Principle Pauli

    Pauli Exclusion Principle (W. Pauli; 1925): No two similar fermions in a system, like electrons in an atom, can contain an identical set of the quantum numbers.

    		•
  • Q : What is Universal age paradox Universal

    Universal age paradox: The two most straightforward techniques of computing the age of the Universe -- via red-shift measurements, and via stellar evolution -- outcome incompatible outcomes. Recent (in mid 1990s) measurements of the distances of far-a

    		•
  • Q : What is Laplace equation Laplace

    Laplace equation (P. Laplace): For the steady-state heat conduction in 1-dimension, the temperature distribution is the explanation to Laplace's equation, which defines that the second derivative of temperature with respect to displac

    		•
  • Q : Fission and Fusion What do you mean by

    What do you mean by Fission and Fusion?

    		•
  • Q : Describe the term ntu in thermodynamics

    Describe the term ntu in thermodynamics? Illustrate in short.

    		•
  • Q : What is Ground source Heat Pumps Ground

    Ground source Heat Pumps (GSHP): This technology makes use of the energy stored in the earth’s crust, which comes mainly from solar radiation. Fundamentally, heat pumps take up heat at a certain temperature and discharge it at a higher temperatu

    		•
  • Q : Define Constancy principle Constancy

    Constancy principle (A. Einstein): One of the postulates of Sir Einstein's special theory of relativity that puts forth that the speed of light in vacuum is computed as similar speed to all observers, in spite of of their relative mot

    		•
  • Q : Explain Event horizon Event horizon:

    Event horizon: The radius which a spherical mass should be compressed to in order to convert it into a black hole, or the radius at which the time and space switch responsibilities. Once within the event horizon, it is basically impossible to escape t

    		•
  • 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.

    		•