--%>

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 : What is Complementarity principle

    Complementarity principle (N. Bohr): The principle that a specified system can’t exhibit both wave-like behavior and particle-like behavior at similar time. That is, some experiments will reveal the wave-like nature of a system,

  • Q : What is Beauty criterion Beauty

    Beauty criterion (Dirac) - The idea that more aesthetically pleasing a theory is the superior it is. In nature this criterion does not stand up to the actual test -- whether or not forecasts of a given theory agree with observational tests -- however

  • Q : How energy transformed in windmills

    Explain how is energy transformed in the windmills?

  • Q : Explain Youngs experiment or

    Young's experiment: double-slit experiment (T. Young; 1801): A well-known experiment that exhibits the wave nature of light (and certainly of other particles). The light is passed from a small source into an opaque screen with the two thin slits. The

  • Q : What is Coriolis pseudoforce Coriolis

    Coriolis pseudoforce (G. de Coriolis; 1835): The pseudoforce that arises since of motion relative to a frame that is itself rotating relative to the second, inertial frame. The magnitude of the Coriolis "force" is tot

  • Q : Kirchhoffs rules or Loop rule or Point

    Explain Kirchhoff's rules or Kirchhoff's Loop rule and Point rule? Kirchhoff's rules (G.R. Kirchhoff) <

  • Q : Define Metre or SI unit of length Metre

    Metre: meter; m: The basic SI unit of length, stated as the length of the path traveled by light in vacuum throughout a period of 1/299 792 458 s.

  • Q : Explain Uncertainty principle

    Uncertainty principle (W. Heisenberg; 1927): A principle, central to the quantum mechanics that states which two complementary parameters (like energy and time, position and momentum, or angular momentum and angular displacement) can’t both be r

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

    What do you mean by the term alloy? Briefly illustrate it.

  • Q : Define Siemens or SI unit of an

    Siemens: S (after E.W. von Siemens, 1816-1892): The derived SI unit of an electrical conductance equivalent to the conductance of an element which has a resistance of 1 O [ohm]; this has units of O-1.