Gravity as Expansion: How Do Orbits Stay Constant?

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SUMMARY

The discussion centers on the theory that gravity results from the expansion of matter, questioning how this theory accounts for the orbital dynamics of satellites and planets. Participants express skepticism about the validity of this theory, particularly its assertion that gravitational forces depend on size rather than mass. The conversation highlights concerns regarding the energy required for matter to expand and the implications of such a theory on our understanding of gravitational interactions. Overall, the participants advocate for a more traditional approach to learning physics to avoid falling into speculative theories.

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  • Understanding of Newtonian gravity and orbital mechanics
  • Familiarity with general relativity concepts
  • Basic knowledge of astrophysics and celestial dynamics
  • Awareness of contemporary physics theories, including string theory
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  • Research the principles of Newtonian gravity and how they apply to orbital motion
  • Explore general relativity and its implications for gravitational forces
  • Investigate the concept of cosmic expansion and its relationship to gravity
  • Study critiques of alternative theories in physics, including string theory
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Students of physics, astrophysicists, and anyone interested in the fundamental principles of gravity and orbital mechanics.

breedb
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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.
 
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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.
 
breedb said:
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.

I thought about that once. Since the moon and the Earth aren't expanding towards each other 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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