--%>
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 : Fundamental principles of the regulation

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

    		•
  • Q : Define Joule-Thomson effect or

    Joule-Thomson effect: Joule-Kelvin effect (J.P. Joule, W. Thomson [later Lord Kelvin]): The change in temperature which takes place whenever a gas expands into an area of lower pressure.

    		•
  • Q : Calculate the concentration A

    A dual-wavelength spectrometer uses 780 nm and 830 nm. The molar extinction coefficients for oxy-hemoglobin (HbO2) and deoxy-hemoglobin (Hb) at these two wavelengths are: e_HbO2_780nm = 710 cm-1M-1, e_Hb_780nm = 1075 cm

    		•
  • Q : What is Hooke law Hooke's law (R.

    Hooke's law (R. Hooke): The stress exerted to any solid is proportional to the strain it generates within the elastic limit for that solid. The constant of that proportionality is the Young modulus of elasticity for that material.

    		•
  • Q : What do you mean by the term cardiac

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

    		•
  • 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 Gaia hypothesis Gaia hypothesis

    Gaia hypothesis (J. Lovelock, 1969): The thought that the Earth as an entire must be regarded as a living organism and that biological procedures stabilize the atmosphere.

    		•
  • Q : What is Edwards-Casimir quantum vacuum

    What is Edwards-Casimir quantum vacuum drive: The hypothetical drive developing the peculiarities of quantum mechanics by restricting permitting wavelengths of the virtual photons on one side of the drive (that is the bow of the ship); the pressure pr

    		•
  • Q : Define Noether theorem Noether theorem

    Noether theorem (Noether): A theorem that explains that symmetries are what gives rise to conserved quantities. For example, the translational symmetry (that is the fact that the laws of physics work the same in all positions) gives r

    		•
  • Q : Define Hertz or SI unit of frequency

    Define Hertz or SI unit of frequency: Hertz: Hz (after H. Hertz, 1857-1894): The derived SI unit of frequency, stated as a frequency of 1 cycle per s; it therefore has units of s-1.

    		•