08-13-2021-2218 - Gravitational Time Dilation (Plane warp)

General relativity
Introduction History Mathematical formulation Tests
show Fundamental concepts
show Phenomena
show Equations Formalisms
show Solutions
show Scientists
Physics portal  Category
v t e

Special relativity
Principle of relativity Theory of relativity
show Foundations
show Consequences
show Spacetime
show Dynamics
show History Precursors
show People
Alternative formulations of special relativity    Physics portal  Category
v t e

This article is about time dilation due to relative gravity. For time dilation due to relative velocity, see Relative velocity time dilation. For the effect on radiation, see gravitational redshift.

Gravitational time dilation is a form of time dilation, an actual difference of elapsed time between two events as measured by observers situated at varying distances from a gravitating mass. The lower the gravitational potential (the closer the clock is to the source of gravitation), the slower time passes, speeding up as the gravitational potential increases (the clock getting away from the source of gravitation). Albert Einstein originally predicted this effect in his theory of relativity and it has since been confirmed by tests of general relativity.^[1]

This has been demonstrated by noting that atomic clocks at differing altitudes (and thus different gravitational potential) will eventually show different times. The effects detected in such Earth-bound experiments are extremely small, with differences being measured in nanoseconds. Relative to Earth's age in billions of years, Earth's core is effectively 2.5 years younger than its surface.^[2] Demonstrating larger effects would require greater distances from the Earth or a larger gravitational source.

Gravitational time dilation was first described by Albert Einstein in 1907^[3] as a consequence of special relativity in accelerated frames of reference. In general relativity, it is considered to be a difference in the passage of proper time at different positions as described by a metric tensor of space-time. The existence of gravitational time dilation was first confirmed directly by the Pound–Rebka experiment in 1959, and later refined by Gravity Probe A and other experiments. 

https://en.wikipedia.org/wiki/Gravitational_time_dilation