Anti-Gravity Logistics: Pinned to Planet or Beyond?

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Discussion Overview

The discussion revolves around the hypothetical scenario of an object losing its gravitational pull and its implications on motion, reference frames, and potential connections to sci-fi concepts of anti-gravity. Participants explore theoretical aspects, including the behavior of objects in gravitational fields and the influence of other forces.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants question whether an object losing gravity would continue in a straight line or be affected by other forces, such as tethering or buoyancy.
  • One participant suggests that if gravity were absent, the object would not exert gravitational force, but would still fall under normal gravitational conditions if in a gravitational field.
  • Another participant argues that starting with a premise of losing gravity is akin to discussing scenarios where fundamental laws of physics do not apply, implying a lack of fruitful inquiry.
  • A participant references a fictional account from "First Men on the Moon," suggesting that an object losing gravity would fly off in a straight line unless influenced by other forces, while also noting a specific error in the portrayal of gravity in that context.
  • There is a suggestion that the other fundamental forces could still apply, allowing for the possibility of tethering the object to the ground, assuming it does not experience repulsion from gravity.

Areas of Agreement / Disagreement

Participants express differing views on the implications of losing gravity, with some emphasizing the theoretical nature of the question and others engaging with specific scenarios and fictional references. The discussion remains unresolved regarding the practical implications and interpretations of such a scenario.

Contextual Notes

Participants acknowledge the complexities involved in discussing gravity, mass, and the effects of other forces, highlighting that the scenario involves assumptions that may not align with established physical laws.

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
It's not a very fruitful approach to learning about Physics of you start off with a statement about Magic.
 
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.
 

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