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. E

    Gravitational time dilation question

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  2. G

    Understanding the Twin Paradox: Breaking the Symmetry in Time Dilation

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  3. S

    Can someone explain this time dilation problem to me?

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  4. S

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  5. Q

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  6. S

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  7. R

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  8. R

    Can someone explain Gravitational Time dilation?

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  9. R

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  10. J

    Time Dilation and Future Interstellar Travel

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  11. W

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  12. D

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  13. E

    Combining Time Dilation from velocity and gravity

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  14. M

    Time dilation b/c of Gravitaional field strength

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  15. C

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  16. D

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  17. D

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  18. A

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  19. R

    Time dilation before Einstein

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  20. K

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  21. K

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  22. jinksys

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  23. D

    Time dilation in uniform field?

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  24. Grimble

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  25. S

    Confused about Velocity Based Time Dilation

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  26. S

    Some Burning Questions about Time Dilation

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  27. A

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  28. S

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  29. M

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  30. N

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  31. M

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  32. V

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  33. I_am_learning

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  34. N

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  35. A

    Time dilation effects on spinning object

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  36. A

    Time Dilation, who is aging slower?

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  37. G

    Gravity: Time Dilation or Death

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  38. T

    Exploring the Interplay of Time & Change: Examining Time Dilation

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  39. D

    Does time dilation cause redshift?

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  40. J

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  41. Negatratoron

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  42. P

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  43. DuckAmuck

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  44. F

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  45. L

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  46. P

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  47. zonde

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  48. M

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  49. M

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  50. P

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