A report onSpeed of light

Universal physical constant that is important in many areas of physics.

- Speed of light

Special relativity

1) The laws of physics are invariant (that is, identical) in all inertial frames of reference (that is, frames of reference with no acceleration).

1) The laws of physics are invariant (that is, identical) in all inertial frames of reference (that is, frames of reference with no acceleration).

2) The speed of light in vacuum is the same for all observers, regardless of the motion of the light source or observer.

In physics, electromagnetic radiation (EMR) consists of waves of the electromagnetic (EM) field, propagating through space, carrying electromagnetic radiant energy.

In physics, electromagnetic radiation (EMR) consists of waves of the electromagnetic (EM) field, propagating through space, carrying electromagnetic radiant energy.

In a vacuum, electromagnetic waves travel at the speed of light, commonly denoted c.

Albert Einstein

German-born theoretical physicist, widely acknowledged to be one of the greatest and most influential physicists of all time.

German-born theoretical physicist, widely acknowledged to be one of the greatest and most influential physicists of all time.

Observationally, the effects of these changes are most apparent at high speeds (where objects are moving at speeds close to the speed of light).

Luminiferous aether

The postulated medium for the propagation of light.

The postulated medium for the propagation of light.

In addition, Maxwell's equations required that all electromagnetic waves in vacuum propagate at a fixed speed, c.

Light

Electromagnetic radiation within the portion of the electromagnetic spectrum that is perceived by the human eye.

Electromagnetic radiation within the portion of the electromagnetic spectrum that is perceived by the human eye.

Its speed in a vacuum, 299 792 458 metres a second (m/s), is one of the fundamental constants of nature.

Spacetime

Mathematical model that combines the three dimensions of space and one dimension of time into a single four-dimensional manifold.

Mathematical model that combines the three dimensions of space and one dimension of time into a single four-dimensional manifold.

The speed of light in a vacuum is the same for all observers, regardless of the motion of the light source.

General relativity

Geometric theory of gravitation published by Albert Einstein in 1915 and is the current description of gravitation in modern physics.

Geometric theory of gravitation published by Albert Einstein in 1915 and is the current description of gravitation in modern physics.

(The defining symmetry of special relativity is the Poincaré group, which includes translations, rotations, boosts and reflections.) The differences between the two become significant when dealing with speeds approaching the speed of light, and with high-energy phenomena.

Photon

Elementary particle that is a quantum of the electromagnetic field, including electromagnetic radiation such as light and radio waves, and the force carrier for the electromagnetic force.

Elementary particle that is a quantum of the electromagnetic field, including electromagnetic radiation such as light and radio waves, and the force carrier for the electromagnetic force.

Photons are massless, so they always move at the speed of light in vacuum, 299,792,458 m/s (or about 299792458 m/s).