--%>

Define Constancy principle

Constancy principle (A. Einstein): One of the postulates of Sir Einstein's special theory of relativity that puts forth that the speed of light in vacuum is computed as similar speed to all observers, in spite of of their relative motion. That is, if I'm travelling at 0.9 c away from you, and fire a beam of light in that direction, both you and I will separately compute the speed of that beam as c.

One of the outcomes of this postulate (i.e., one of the predictions of the special relativity) is that no massive particle can be accelerated to (or beyond) the light speed, and therefore the speed of light also symbolizes the eventual cosmic speed limit. Only mass-less particles (collectively termed as luxons, comprising photons, gravitons, and probably neutrinos, must they prove to indeed be mass-less) travel at light speed, and all other particles should travel at slower speeds.

   Related Questions in Physics

  • Q : Define Permittivity of free space or

    Permittivity of free space: electric constant; epsilon_0: The ratio of the electric displacement to the intensity of the electric field generating it in vacuum. It is equivalent to 8.854 x 10-12 F/m.

  • Q : What is Kerr effect Kerr effect (J.

    Kerr effect (J. Kerr; 1875): The capability of certain substances to refract light waves in a different way whose vibrations are in dissimilar directions whenever the substance is located in an electric field.

  • Q : Explain Stern-Gerlach experiment

    Stern-Gerlach experiment (O. Stern, W. Gerlach; 1922): The experiment which explains the features of spin (that is intrinsic angular momentum) as a different entity apart from the orbital angular momentum.

  • Q : Report on Radiobiology for Travel Space

    I have a problem in wirting a report on Radiobiology for Travel Space.  Can someone provide me a complete report on the above topic.

  • Q : Current through resistors How do I find

    How do I find out a maximum current flowing through a resistor with just the resistance of the resistor and it's power rating?

  • Q : Elementary particles concepts Write

    Write down any two elementary particles that have nearly infinite life time?

  • Q : Define Schwarzschild radius

    Schwarzschild radius: The radius ‘r’ of the event horizon for a Schwarzschild black hole of mass m is specified by (in geometrized units) r = 2 m. In its conventional units: r = 2 G m/c2

  • Q : Describe Wiedemann-Franz law

    Wiedemann-Franz law: It is the ratio of the thermal conductivity of any pure metal (substance) to its electrical conductivity is just about constant for any specified temperature. This law holds pretty well apart from at low temperatures.

  • Q : What is Ultraviolet catastrophe

    Ultraviolet catastrophe: It is the shortcoming of Rayleigh-Jeans formula that attempted to explain the radiance of a blackbody at different frequencies of the electromagnetic spectrum. This was clearly wrong since as the frequency rose, the radiance r

  • Q : Bell's inequality Bell's inequality

    Bell's inequality (J.S. Bell; 1964) - The quantum mechanical theorem that explains that if the quantum mechanics were to rely on the hidden variables, it should have non-local properties.