--%>

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 : Brewster's law Brewster's law (D.

    Brewster's law (D. Brewster) - The extent or level of the polarization of light reflected from a transparent surface is maximum whenever the reflected ray is at right angle to the refracted ray.  

  • 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 : Features or characteristics of dead

    Write a short note on the features or characteristics of dead stars?

  • Q : Define Ehrenfest paradox Ehrenfest

    Ehrenfest paradox (Ehernfest, 1909): The special relativistic "paradox" including a fast rotating disc. As any radial segment of the disc is perpendicular to the direction of motion, there must be no length contraction of the radius;

  • Q : Conservation laws and illustrations of

    Explain Conservation laws and illustrations of conservation laws (Conservation of mass-energy, electric charge, linear momentum and angular momentum) ? Conservation laws: The law which states that,

  • Q : Problem on multiplexed channels 4

    4 channels, two with a bit-rate of 200 kbps and two with a bit-rate of 150 Kbps are to be multiplexed employing multiple slots TDM with no sync bits. a. Find out the size of a frame in bits?

    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 : Acceleration during this interval The

    The velocity of a body was observed to be constant throughout five minutes of its motion. Determine its acceleration during this interval?

  • Q : Explain Coulombs law Coulomb's law (C.

    Coulomb's law (C. de Coulomb): The basic law for electrostatics, equivalent to Newton's law of universal gravitation. It defines that the force between two point charges is proportional to the arithmetical product of their respective

  • Q : Explain Lagrange points Lagrange points

    Lagrange points: The points in the vicinity of two massive bodies (like the Earth and Moon) with each others' relevant gravities balance. There are five, labeled L1 via L5. L1, L2, and L3 lie all along the centerline among the centers