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If light were instantaneous

  1. Jun 20, 2005 #1
    How would our present universe appear to us if light and gravity were either instantaneous since the big bang, or gradually so, marked by relatively recent events?
  2. jcsd
  3. Jun 20, 2005 #2
    Then we would have not used the term " from place A to place B" , because everything would be instantaneous, a phenomena at one place could be seen simultaneously by different observers.

    The amount of Gravitational field at one place would remain same due to a particular source , The earth would rotate in the same exact orbit as before but the light from sun would not take more than 8 minutes to reach us but it would be an instantaneous process and the change in gravitational field around us would be instantaneous , there would be rapid change in fields around us .

    If the sun would have lost itself somewhere , the gravitational attraction due to sun would dimnish immediately, the same instant the sun loses itself , the same instant we would lose the orbit .

    Ofcourse the days would be longer , we would be able to spot the sun 8 minutes before, and maybe a bit more earlier.

    Special Relativity would not have been important at all , the 'cause' and 'effect' would take place simultaneously.Travelling at speed of light would not have been controversial ,

    SETI people would feel a sigh of relief , as sending mesages to other civilations would not have been that difficult , the limitations of radiowave-instruments as a message transfer device would not have been a problem.
  4. Jun 20, 2005 #3


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    We wouldn't be able to study galaxies that formed shortly after the big bang. More galaxies would look like the Milky Way. We wouldn't have a clue as to the age of the universe. And when you talked on the phone to people overseas, that annoying 1/4 - 1/2 second lag would be gone.
  5. Jun 20, 2005 #4


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    You might want to think this one through a bit. :rolleyes:
  6. Jun 20, 2005 #5


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    If the universe is infinite, then the night sky would be as bright as the surface of the sun.

    We would have no knowledge of the past history of the universe.
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