Special Relativity

[ spĕsh′əl ]

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The theory of space and time developed by Albert Einstein, based on the postulates that all the laws of physics are equally valid in all reference frames moving at a constant speed relative to each other (that is, in all inertial frames), and that the speed of light is observed to be the same in all reference frames. To compare measurements of length or time made in different inertial frames, their values must be regarded as components of vectors in a 4-dimensional space called Minkowski space-time. Different frames are related to each other mathematically by Lorentz transformations. Special Relativity predicts that all massless particles, such as photons, are always necessarily moving at the speed of light, while all particles with mass are always necessarily moving slower than the speed of light, and only particles with mass can be at rest. The theory also states that velocities are not simply additive. For example, if an object (such as a spacecraft) moving with velocity v1 observes another faster object (such as a rocket fired from the spacecraft) moving ahead of it in the same direction with velocity v2, an observer at rest observes the faster object moving at velocity that is not just the sum of v1 and v2, but at the slower speed v1 + v21 + v1v2c2. See also General Relativity time dilation.

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Words nearby Special Relativity

special partnership, special plea, special pleading, special privilege, special prosecutor, Special Relativity, special rule, special school, special sense, special session, special sort

How to use Special Relativity in a sentence

As for the federal authorities, they have made themselves available but the clergy have not requested special protection.
Mexico’s Priests Are Marked for Murder|Jason McGahan|January 7, 2015|DAILY BEAST
At the same time, campaigns are spending less while the special-interest groups are spending more.
The 100 Rich People Who Run America|Mark McKinnon|January 5, 2015|DAILY BEAST
The off-year special election into which Duke threw himself drew little media notice at first.
The Louisiana Racists Who Courted Steve Scalise|Jason Berry|January 3, 2015|DAILY BEAST
All of the big cats have a special mystique, but perhaps none more so than the tiger.
This Tiger Has Some Serious Ups|Jack Holmes, The Daily Beast Video|January 2, 2015|DAILY BEAST

It all sounds a bit dramatic, but that cactus feels like something special.
Lost For Thousands of Strokes: 'Desert Golfing' Is 'Angry Birds' as Modern Art|Alec Kubas-Meyer|January 2, 2015|DAILY BEAST
For this use of the voice in the special service of will-power, or propelling force, it is necessary first to test its freedom.
Expressive Voice Culture|Jessie Eldridge Southwick
Diplococci without capsules are common in the sputum, but have no special significance.
A Manual of Clinical Diagnosis|James Campbell Todd
Will the new issues promptly retire when their special task is over?
Readings in Money and Banking|Chester Arthur Phillips
Instead of the expected general amnesty, only a few special pardons were granted.
The Philippine Islands|John Foreman
The result of this mission was eminently successful; a special treaty was drawn up and Spain sold Louisiana to France.
Napoleon's Marshals|R. P. Dunn-Pattison