Anti-Gravity Logistics: Pinned to Planet or Beyond?

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Frost Dragon
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If an object was to lose its gravity for any reason, would it lose its reference frame to the planet and sun. Therefore keep going in a straight line? Or is there some other force that would keep it pinned to the planet. Also does this have any application to sci-fi anti gravity would it also fly off the planet?
 
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Frost Dragon said:
If an object was to lose its gravity for any reason, would it lose its reference frame to the planet and sun. Therefore keep going in a straight line? Or is there some other force that would keep it pinned to the planet. Also does this have any application to sci-fi anti gravity would it also fly off the planet?
Your question amounts to "if the laws of physics did not apply then what would the laws of physics say about <insert nonsense of your choice>?"
 
Basically, "no". Of course, there are problems with having a non-positive gravity, and therefore a non-positive mass.
But if we ignore those problems, we still have an object is a normal Sun/Moon/Earth gravitational field that will "fall" in the normal way.

However, having zero rest mass and being at rest, it would not exert a gravitatoinal force on anything else.
 
Ok thanks, I think that helps me.
 
Frost Dragon said:
If an object was to lose its gravity for any reason, would it lose its reference frame to the planet and sun. Therefore keep going in a straight line? Or is there some other force that would keep it pinned to the planet. Also does this have any application to sci-fi anti gravity would it also fly off the planet?

Well, there are still 3 other fundamental forces that apply. You could simply tether the object to the ground if you wanted to. Of course, that assumes that the object just ignores gravity, not that it is repelled by it.
 
It's like asking if time didn't exist, would anything happen?
Time does exist though, and so does gravity.
 
Cavor explained it in First Men on the Moon. Yes, an object that loses its gravity would fly off the Earth in a straight line following Earth rotation... unless additional forces apply, like buoyancy of air causing it to rise even faster.
A problem is that cavorite blocked gravity in straight line. In First Men on the Moon, this caused a house containing a cavorite sheet to blow up as the whole air column above lost weight. Well, that was an error... centre of Earth is not actually a point mass.