--%>

What is Hubble constant

Hubble constant: H0 (E.P. Hubble; 1925): The constant that determines the relationship among the distance to a galaxy and its velocity of recession due to the growth of the Universe. As the Universe is self-gravitating, it is not truthfully constant. In cosmology, it is stated as

H = (da/dt)/a,

Here a is the 4-radius of the Universe. Whenever computed for the present, it is written as:

H0 == H (t = now)

The Hubble constant is not acknowledged to great accuracy (only in about a factor of 2), however is believed to lie someplace between 50 and 100 km/s/Mpc.

   Related Questions in Physics

  • Q : Define Lumen or SI unit of luminous flux

    Lumen: lm: The derived SI unit of luminous flux, stated as the luminous flux produced by a uniform point source of 1 cd releasing its luminous energy over a solid angle of 1 sr; it therefore has units of cd sr.

  • Q : Define Fermi paradox Fermi paradox (E.

    Fermi paradox (E. Fermi): E. Fermi's inference, simplified with the phrase, "Where are they?" questioning that when the Galaxy is filled with intelligent and scientific civilizations, why haven't they come to us hitherto? There are nu

  • Q : What is Arago spot What is  Arago

    What is Arago spot? The bright spot which appears in the shadow of a consistent disc being backlit by monochromatic light originating from a point source. &n

  • Q : Explain Poisson equation and Poisson

    Explain Poisson equation and Poisson spot: Poisson equation (S.D. Poisson): The differential form of Gauss' law, that is, div E = rho, Pois

  • Q : Faradays laws of electromagnetic

    Explain Faraday's laws of electromagnetic induction and explain Faraday's first, second and third law of electromagnetic induction? Faraday's laws of electromagnetic in

  • Q : Define Fermats principle Fermat's

    Fermat's principle: principle of least time (P. de Fermat): The principle, put onward by P. de Fermat that explains the path taken by a ray of light among any two points in a system is for all time the path which takes the least time.

  • Q : Explain Drake equation Drake equation

    Drake equation (F. Drake; 1961): The method of estimating the number of intelligent, scientific species (that is, able to communicate with other species) in subsistence in our space. N

  • Q : Why electron and proton encompass

    Explain in short why electron and proton encompass similar charge while the proton is 1836 times heavier?

  • Q : Define Ideal gas constant or universal

    Define Ideal gas constant or universal molar gas constant? Ideal gas constant: or universal molar gas constant; R: The constant which appears in the ideal gas equation. It is equivalent to

  • Q : Define Joule or SI unit of energy Joule

    Joule: J (after J.P. Joule, 1818-1889): The derived SI unit of energy stated as the quantity of work done by moving an object via a distance of 1 m by exerting a force of 1 N; it therefore has units of N m.