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What is the speed of dark? (space)

  1. Sep 4, 2004 #1
    My question is what is the speed of dark?

    Does space the black of space have a speed?

    Many Thanks
    Blair Styles
  2. jcsd
  3. Sep 4, 2004 #2
    darkness is the absense of light
    so in that aspect it always everywhere, but can't be added or removed faster than c.
  4. Sep 4, 2004 #3


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    try c..........
  5. Sep 4, 2004 #4

    c can change
    what i was saying given the speed of c in the environment darkness is limited by it.
  6. Sep 4, 2004 #5
    or you could say that darkness is instantious and that light is just in the way of it but it is there its just that photons are blocking it and that when they are gone it is instnatly there.
  7. Sep 5, 2004 #6
    Darkness is the abscence of light, therefore the speed of darkness is the speed it arrives, therefore the same as the speed of the departure of light. The speed of darkness = the speed of light
  8. Sep 5, 2004 #7
    c, the speed of light in vacuum, is a fundamental constant of nature, to wit 299.792.458 m/s precisely (because it defines the meter). So it cannot change. The speed of light in a can change though depending on the medium.
  9. Sep 5, 2004 #8


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    It depnds what you mean by the 'speed of dark as it could be interpreted in sevral ways. For example there is no limit on the coordinate velocity of a shadow.
  10. Sep 5, 2004 #9
    So you're the one that has found the "precise" speed of light in a vacuum. I look foward to reading your papers. I'm espically interested in how you created a perfect vacuum to test it. Maybe you should have said the aproximate speed of light in a vacuum is .....and whats this part about it defining the meter?

    The speed of darkness is 0. It does not move, travel, or propigate in any way. It may appear that way, and the comments saying it is relative to the speed of light seem consistant with our observations. One might ask what is the speed of no electricity in a conductor.
    Last edited: Sep 5, 2004
  11. Sep 5, 2004 #10
    when I said c changes it was assumed i meant in accordance with differnt mediums
  12. Sep 5, 2004 #11
    It's really just a matter of notation but c is the value of the speed of light in vacuum. So it's better to say, the speed of light (not c) is different for different media.

    About the speed of light in a vacuum; it is exactly 299792458 m/s because it is the definition of the meter. A meter is the distance light travels in a vacuum in 1/299792458 second. So If the speed of light in vacuum turns out to be a little different than previously measured this changes the distance of one meter and not the constant c!
  13. Sep 5, 2004 #12
    My next question is based on the statment that you said "The speed of darkness is 0".
    My question is if this is true then what about a black hole's does it move in space if the answer is yes then i must ask again.
    What is the speed of dark?
  14. Sep 6, 2004 #13


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    "Dark" is not a well-defined physical concept, so this thread cannot possibly be anything but philosophical. I am thus moving it.

    - Warren
  15. Sep 6, 2004 #14
    Thank you for moving my post i was unable to define my question as to ascertaining the right place to ask if space can be used as a form of energy by using the sound from a planet to generate enough power to start a black hole thus traveling in time.

    Many Thanks
    Blair Styles
  16. Sep 6, 2004 #15
    Darkness is a well defined physical concept it is the absense of light, duh! However, the vacuum flux guarantees their will always be some small amount of light as long as there is spacetime. Hence, what we call darkness is relative and obeys the Uncertainty Principle. This means, of course, that it's speed can be greater than that of light, especially since it carries no energy or information.
  17. Sep 6, 2004 #16
    Space had information in it?
    What about planet earth and the sun they full of information and can also generate energy that energy can be used as power or am i way off?

    If the sun makes a sound then that energy must move in space or does space move the energy?
    Last edited: Sep 6, 2004
  18. Sep 6, 2004 #17


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    Ohhh... well, in that case, this belongs in TD, and you deserve a warning. Personal theories are not welcome here, and you are thus in violation of PF guidelines. This is a science website, not a science fiction website.

    - Warren
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