Definition of relativity
1a : the quality or state of being relativeb : something that is relative
2 : the state of being dependent for existence on or determined in nature, value, or quality by relation to something else
3a : a theory which is based on the two postulates (1) that the speed of light in a vacuum is constant and independent of the source or observer and (2) that the mathematical forms of the laws of physics are invariant in all inertial systems and which leads to the assertion of the equivalence of mass and energy and of change in mass, dimension, and time with increased velocity —called also special relativity, special theory of relativityb : an extension of the theory to include gravitation and related acceleration phenomena —called also general relativity, general theory of relativity
4 : relativism 1b
Recent Examples of relativity from the Web
Einstein’s theory of general relativity perfectly explained Mercury’s 43 arcsecond procession.
But Einstein’s theory of general relativity is holding up quite well:
The findings also allowed scientists to probe the limits of Einstein's theory of general relativity further by looking to see whether the gravitational waves underwent dispersion –
Black holes were an entirely unwelcome consequence of his theory of general relativity that ascribes gravity to the warping of space-time geometry by matter and energy.
Alcubierre had set out to determine whether the concept of faster-than-light travel was feasible within the constraints of general relativity.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'relativity'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
First Known Use of relativity
RELATIVITY Defined for English Language Learners
Definition of relativity for English Language Learners
physics : a theory developed by Albert Einstein which says that the way that anything except light moves through time and space depends on the position and movement of someone who is watching
Seen and Heard
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