What is Time dilation: Definition and 999 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. D

    Time dilation in biological processes

    Has time dilation ever been observed to occur in biological processes (e.g. the rate at which bacteria divides)? Thanks.
  2. B

    How Does Gravitational Time Dilation Work?

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  3. F

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  5. T

    Length contraction and time dilation equivelant?

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  6. P

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  9. A

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  11. T

    Very simple thought experiment re: time dilation

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  12. N

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  13. I

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  14. T

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  15. S

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  16. H

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  18. D

    What happens biologically during time dilation?

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  19. R

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  20. M

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  23. S

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  25. C

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  35. J

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  36. T

    Understanding Time Dilation in Special Relativity

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  37. S

    The doppler effect and time dilation context

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  38. T

    Explaining Special Relativity's Time Dilation

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  39. M

    Time dilation and space travel

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  40. E

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  41. B

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  42. E

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  44. K

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  45. T

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  46. TurtleMeister

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  47. C

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  48. N

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  49. Z

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