What is Time delay: Definition and 44 Discussions

The Shapiro time delay effect, or gravitational time delay effect, is one of the four classic solar-system tests of general relativity. Radar signals passing near a massive object take slightly longer to travel to a target and longer to return than they would if the mass of the object were not present. The time delay is caused by spacetime dilation, which increases the time it takes light to travel a given distance from the perspective of an outside observer. In a 1964 article entitled Fourth Test of General Relativity, astrophysicist Irwin Shapiro wrote:

Because, according to the general theory, the speed of a light wave depends on the strength of the gravitational potential along its path, these time delays should thereby be increased by almost 2×10−4 sec when the radar pulses pass near the sun. Such a change, equivalent to 60 km in distance, could now be measured over the required path length to within about 5 to 10% with presently obtainable equipment.

Throughout this article discussing the time delay, Shapiro uses c as the speed of light and calculates the time delay of the passage of light waves or rays over finite coordinate distance according to a Schwarzschild solution to the Einstein field equations.

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  1. brotherbobby

    Different sunset times due to elevation ##h## at a point on the Earth

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  2. tommy7

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  3. jackmiller2003

    I Time Delay Information Transfer with Entangled Particles

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  4. C

    I Time Delay on Multiple Photons when travelling from one plac

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  5. supak111

    Make a very simple mechanical time delay?

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  6. Abdul Wali

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  7. N

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  8. N

    Understanding time delay estimation for GPS?

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  9. A

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  10. N

    How to calculate the time delay based on a function of antenna angle?

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  11. K

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  12. salaheddine

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  13. S

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  14. supak111

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  15. JasonR2

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  16. L

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  17. C

    Why the Shapiro delay is calculated with respect to the....?

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  18. L

    Does impedance affect time delay in digital circuits?

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  19. T

    Calculating Time Delay for Radio Telescope Pointing

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  20. K

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  21. M

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  22. N

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  23. R

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  24. A

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  25. J

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  26. perplexabot

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  27. M

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  28. G

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  29. F

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  30. C

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  31. C

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  32. S

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  33. J

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  34. N

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  35. B

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  36. E

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  37. E

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  38. M

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  39. Y

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  40. A

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  41. T

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  42. D

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  43. A

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  44. B

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