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. johann1301

    Time Distortion and Time Dilation

    Is there a difference between Time Distortion and Time Dilation? If so, what's the difference?
  2. R

    Spacetime dilation in special relativity

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  3. K

    Time dilation - Lorentz transformation using light clock

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  4. grav-universe

    Gravitational time dilation

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  5. I

    Time Dilation Data Sets: Get Graphs & Experiments Results

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  6. M

    Calculating Muon Half-Life: Length Contraction vs Time Dilation

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  7. C

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  8. T

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  9. P

    General Relativity: Gravitational time dilation of photons and Fabric of Space

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  10. S

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  11. I

    Confirming Time Dilation Without Subatomic Particles: Steven's Question

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  12. Rapier

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  13. I

    Time dilation from length contraction

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  14. D

    What are your best arguments for time dilation, so duration is different ?

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  15. J

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  16. S

    Max/Min Time Dilation: What is the Scale?

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  17. D

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  18. D

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  19. Z

    Time Dilation Scenario: Einstein's Skaters on a Moving Conveyor Belt

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  20. R

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  21. G

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  22. D

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  23. J

    Special Relativity: Time Dilation

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  24. M

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  25. S

    Relativity: Time Dilation and Length Contraction

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  26. S

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  27. A

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  29. K

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  30. C

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  31. S

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  32. S

    Does radioactivity suffer time dilation?

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  33. K

    Time dilation and Length contraction in Saddle Geometries

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  34. E

    Time dilation derivations - help me out just looking for references

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  35. H

    Atomic Clock Time Dilation Experiment

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  36. X

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  37. S

    Is My Time Dilation Equation Correct?

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  38. Nakshatra

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  39. M

    Time Dilation in a Non-Rotating Laser Sphere: Inside vs Outside

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  40. J

    Does a clock in free-fall slow due to gravitational time dilation?

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  41. G

    Time Dilation and Length Contraction the same thing?

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  42. D

    Why are the effects of Time Dilation permanent but Length Contraction is Not?

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  43. PrincePhoenix

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  44. Z

    How Fast is a Clock Moving if It Runs Four Times Slower?

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  45. S

    How can the rest observer conclude the photon travels at an angle?

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  46. A

    What is the result of this laser/time dilation scenario?

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  47. P

    Time Dilation at Center of a Neutron Star

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  48. Q

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  49. M

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  50. G

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