What is Dilation: Definition and 1000 Discussions

In physics and relativity, time dilation is the difference in the elapsed time as measured by two clocks. It is either due to a relative velocity between them (special relativistic "kinetic" time dilation) or to a difference in gravitational potential between their locations (general relativistic gravitational time dilation). When unspecified, "time dilation" usually refers to the effect due to velocity.
After compensating for varying signal delays due to the changing distance between an observer and a moving clock (i.e. Doppler effect), the observer will measure the moving clock as ticking slower than a clock that is at rest in the observer's own reference frame. In addition, a clock that is close to a massive body (and which therefore is at lower gravitational potential) will record less elapsed time than a clock situated further from the said massive body (and which is at a higher gravitational potential).
These predictions of the theory of relativity have been repeatedly confirmed by experiment, and they are of practical concern, for instance in the operation of satellite navigation systems such as GPS and Galileo. Time dilation has also been the subject of science fiction works.

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  1. S

    B Time Dilation Effect: Corrections to Clocks on ISS

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  4. R

    I Length contraction and time dilation

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  5. stevendaryl

    I Time-Dependent Lagrangian Leads to Time Dilation?

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  6. Nick tringali

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  7. Julius Ceasar

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  8. C

    B Conflict Between Time Dilation and Red/Blue Shift?

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  11. M

    Why Is Time Dilation Considered a Real Phenomenon?

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  12. C

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  13. R

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  14. S

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  15. Lutz-F

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  16. O

    B Contradictory time dilation equations

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  17. jaketodd

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  18. richengle

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  19. J

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  20. U

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  21. T

    B On time dilation and length contraction

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  24. X

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  27. V

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  29. W

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  30. D

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  31. Sabertooth

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  33. Mattv

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  34. YouAreAwesome

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  35. P J Strydom

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  36. ersa17

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  37. docnet

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  38. J

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  39. just dave

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  40. arkantos

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  41. PainterGuy

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  42. penroseandpaper

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  43. E

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  45. Julius Ceasar

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  46. Haorong Wu

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  47. Chris Miller

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  48. S

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  49. G

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  50. M

    Special Relativity question using Lorentz Transformation time dilation

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