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Gravity as Expansion

  1. Aug 25, 2008 #1
    I read about the theory that gravity is caused by the expansion of matter. If this is true, how does this account for the change of direction of a satellite or planet that occurs when it orbits another larger object.

    It seems that if the object is moving fast enough to maintain its orbit it would appear to rotate approaching 90 degrees from where it started around the planet but never reaching 90 degrees. Then it would appear to be traveling away from Earth.
  2. jcsd
  3. Aug 26, 2008 #2

    Vanadium 50

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    That "theory" sounds like pure crackpottery to me. For instance, it predicts that gravitational forces depend on size and not the mass. I suspect that if you want details on how it's supposed to work, you need to talk to the people who created it.
  4. Aug 26, 2008 #3
    I thought about that once. Since the moon and the earth aren't expanding towards eachother really fast that would have to mean that space is expanding along with the matter, but as far as I know there's no good reason either one should ultimately want to do that. You'd have to wonder where the energy to accomplish this comes from and where it goes.

    There seems to be a temptation in people to explain everything with what limited information they have on hand, and the ones who get carried away become the crackpots we know and love. I'm suspicious of string theory purely on the grounds that it seems to be reaching to far too fast. I'm learning about physics the old fashioned way to avoid the path of the crackpot but wow is it daunting.
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