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# Speed of light/Related Articles

From Citizendium, the Citizens' Compendium

*See also changes related to Speed of light, or pages that link to Speed of light or to this page or whose text contains "Speed of light".*

## Parent topics

## Subtopics

- Atomic units [r]: A system of units convenient for atomic and molecular calculations.
^{[e]} - Frame of reference (physics) [r]: An observational set of coordinates tied to the motion of an observer, used to describe physical events and possibly including a measurement apparatus.
^{[e]} - Inertial frame of reference [r]: A frame of reference in which the laws of physics take their simplest form.
^{[e]} - Free space (electromagnetism) [r]: In classical electromagnetism, the vacuum reference state with no fields or particles; in quantum mechanics, the vacuum state with electromagnetic fields fluctuating about an average value of zero.
^{[e]} - Vacuum (quantum electrodynamic) [r]: The term
*quantum electrodynamic vacuum*, or QED vacuum, refers to the ground state of the electromagnetic field, which is subject to fluctuations about a dormant zero average-field condition.^{[e]} - Metre (unit) [r]: Unit of length; one of the seven SI base units.
^{[e]} - Second (physics) [r]: Unit of time; one of the seven SI base units.
^{[e]} - Time [r]: A fundamental quantity in physics - that what differs always between two inspections of the same system by the same observer.
^{[e]}

## Bot-suggested topics

Auto-populated based on Special:WhatLinksHere/Speed of light. Needs checking by a human.

- Albert Einstein [r]: 20th-century physicist who formulated the theories of relativity.
^{[e]} - Biot-Savart's law [r]:
*Add brief definition or description* - Black hole [r]: Area of space-time with a gravitational field so intense that its escape velocity is equal to or exceeds the speed of light.
^{[e]} - Christiaan Huygens [r]: (14 April 1629 - 8 June 1695) an internationally renowned Dutch mathematician, physicist and astronomer.
^{[e]} - Displacement current [r]: Time derivative of the electric displacement
**D**; Maxwell's correction to Ampère's law.^{[e]} - Electric constant [r]: A physical constant in the International System of Units (SI) relating capacitance to area in classical vacuum with an exact value
*ε*= 10_{0}^{7}/(4πc_{0}^{2}) F/m,*c*being the defined value for the speed of light in classical vacuum in the SI units._{0}^{[e]} - Electric field [r]: force acting on an electric charge—a vector field.
^{[e]} - Electromagnetic radiation [r]: a collection of electromagnetic waves, usually of different wavelengths.
^{[e]} - Electromagnetic spectrum [r]: The range of electromagnetic waves covering all frequencies and wavelengths.
^{[e]} - Electromagnetic wave [r]: A change, periodic in space and time, of an electric field
**E**(**r**,t) and a magnetic field**B**(**r**,t); a stream of electromagnetic waves, referred to as electromagnetic radiation, can be seen as a stream of massless elementary particles, named photons.^{[e]} - Ether (physics) [r]: Medium that can carry electromagnetic waves (obsolete)
^{[e]} - Frequency [r]: For a periodic (i.e., repeating) phenomena, the number of repetitions per unit of time, usually one second; measured in Hertz
^{[e]} - Gaussian units [r]: A centimeter-gram-second system of units often used in electrodynamics and special relativity.
^{[e]} - Gravitational lens [r]: A lens formed when light from a very distant, bright source (such as a quasar) is 'bent' around a massive object (such as a cluster of galaxies) between the source object and the observer.
^{[e]} - Hendrik Antoon Lorentz [r]: Dutch theoretical physicist (1853 - 1928)
^{[e]} - James Clerk Maxwell [r]: (1831 – 1879) Scottish physicist best known for his formulation of electromagnetic theory and the statistical theory of gases.
^{[e]} - Joule [r]: The SI unit of energy (symbol: J) which is a measure of the capacity to do work or generate heat.
^{[e]} - Lambert W function [r]: Used to solve equations in which the unknown appears both outside and inside an exponential function or a logarithm.
^{[e]} - Laser rangefinder [r]: A device, analogous to radar but using light rather than radio waves, which measures the distance to an object of interest.
^{[e]} - Light day [r]: Distance that light travels in a vacuum in one day; 1 light day = 25,902,068,371,200 m = 2.5902067 * 10
^{13}m.^{[e]} - Light hour [r]: Distance that the light travels in vacuum in one hour, 1.0792528 * 10
^{12}m^{[e]} - Light minute [r]: Distance that light travels in vacuum in one minute; 17,987,547,480 m = 1.7987547 * 10
^{10}m.^{[e]} - Light second [r]: Distance that light travels in vacuum in one second; 2.99792458 * 10
^{8}m.^{[e]} - Lightning [r]: An atmospheric discharge of electricity accompanied by thunder, which typically occurs during thunderstorms, and sometimes during volcanic eruptions or dust storms.
^{[e]} - Lorentz force [r]: Force on an electrically charged particle that moves through a magnetic and an electric field.
^{[e]} - Magnetic constant [r]: A physical constant in the International System of Units (SI) relating mechanical force and electric current in classical vacuum with a defined value
*μ*= 4_{0}*π*× 10^{−7}N/A^{2}.^{[e]} - Mass [r]: The total amount of a substance, or alternatively, the total energy of a substance.
^{[e]} - Maxwell equations [r]: Mathematical equations describing the interrelationship between electric and magnetic fields; dependence of the fields on electric charge- and current- densities.
^{[e]} - Metre (unit) [r]: Unit of length; one of the seven SI base units.
^{[e]} - Momentum [r]: mass of a particle times its velocity (a vector).
^{[e]} - Number [r]: One of the fundamental concepts of mathematics, used for such purposes as counting, ordering, and measuring.
^{[e]} - Oersted (unit) [r]: Unit of magnetic-field strength |
**H**| in the Gaussian system of units; symbol Oe; 1 Oe = 1000/4π A⋅turn/m.^{[e]} - Photon [r]: elementary particle with zero rest mass and unit spin associated with the electromagnetic field.
^{[e]} - Polarizability [r]: The ease by which a charge-distribution polarizes; describes the amount of charge separation caused by an electric field.
^{[e]} - R-hadron [r]: Hypothetical particles composed by a Supersymmetric particle and at least one quark.
^{[e]} - Radiation [r]: Transmission of energy through space.
^{[e]} - Second (physics) [r]: Unit of time; one of the seven SI base units.
^{[e]} - Special relativity [r]: Theory of the effects of motion on observations of things such as length, time, mass and energy. The theory is based on the postulates that all laws of physics are the same in all inertial reference systems, and that the vacuum speed of light is a universal constant, independent of the speed of the source.
^{[e]} - Statcoulomb [r]: Unit of electric charge in cgs-esu units: 1 statC = C/(10⋅
*c*), with*c*the speed of light in m/s.^{[e]} - Statvolt [r]: Unit of electric voltage; symbol statV; 1 statV = 10
^{−6}×*c*volt;*c*speed of light in m/s.^{[e]} - Wavelength [r]: For a repeating phenomenon such as a radio signal with a given frequency, the wavelength is the length, in meters, of a single repetition
^{[e]}