--%>

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 : Explain Schroedingers cat

    Schroedinger's cat (E. Schroedinger; 1935): A thought experiment designed to exemplify the counterintuitive and strange ideas of reality that come all along with the quantum mechanics. A cat is sealed within a clos

  • Q : Explain Casimir effect Casimir effect

    Casimir effect (Casimir): The quantum mechanical effect, where two very big plates positioned close to each other will experience an attractive force, in the nonattendance of other forces. The cause is implicit particle-antiparticle p

  • Q : What is Loschmidt constant or Loschmidt

    Loschmidt constant: Loschmidt number: NL: The total number of particles per unit volume of an ideal gas at standard pressure and temperature. It has the value of 2.687 19 x 1025 m-3.

  • Q : What is Permeability of free space or

    Permeability of free space: magnetic constant: mu_0: The ratio of the magnetic flux density in the substance to the external field strength for vacuum. It is equivalent to 4 pi x 10-7 H/m.

  • 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 : Write a short note on diffuse reflection

    Write a short note on diffuse reflection?

  • 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 : Describe Wien displacement law Wien

    Wien displacement law: For a blackbody, the product result of the wavelength corresponding to the maximum radiances and the thermodynamic temperature is constant, then the Wien displacement law constant. As an outcome, as the temperature increases, th

  • Q : What is Magnetic monopole Magnetic

    Magnetic monopole: The hypothetical particle that comprises sources and sinks of the magnetic field. The magnetic monopoles have never been found, however would only cause pretty minor modifications to the Maxwell's equations. They also appear to be p

  • 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