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Author Topic: Could Earth temporarily lose its gravitational field?  (Read 683 times)

Offline NewWriter

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Hello

I understand this subject has previously been asked by others to some degree on another thread but It did not fully answer my query so I thought I'd raise the question myself to get a more specific answer.

I appreciate any advice given.

My query is about the possibility of how there could be an action or event that could lead to a temporary loss of gravity on Earth, or indeed where there is negative gravity so that people, buildings etc would actually start to rise up towards space before dropping back down and returning to normal.?

I'm specifically thinking of a situation where an event such as another large mass in space EG another celestial body passes by Earth so closely or indeed has an impact with Earth where this could be a possibility ?
Another having a greater mass or gravitational pull or some kind of disturbance which would have this type of effect to happen.

Thank you

NW

« Last Edit: 11/08/2016 22:01:09 by chris »


 

Offline Blame

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Re: Temporarily loss of gravity on Earth
« Reply #1 on: 11/08/2016 09:16:01 »
I am assuming this for a story plot.

You would get effective loss of gravity at a very specific point on earth if there was enough mass above. You might even get a circle with a net pull upwards inside and pull downwards outside.

Catch is you would need ether another planet or a black hole which could be relatively small and local. Ether way I doubt the mess of arrival and departure would leave survivors.

To get the effect you want would require something highly theoretical and controversial. To affect the whole planet evenly on the surface the effect could be centered at the earths core but that would have dramatic effects under the surface. Better to imagine a device that simply removed gravity as an effect of mass over the whole planet. Don't forget that it is gravity that holds the atmosphere down. Anything more than a very temporary loss of gravity and we loose atmosphere for good. 
 

Offline NewWriter

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Re: Temporarily loss of gravity on Earth
« Reply #2 on: 11/08/2016 20:21:23 »
Indeed it is thank you for your reply.

I want it to be at least theoretically possible as there is nothing worse than a gaping plot hole with the scientific theory.

The essential effect I was hoping to explain was like a temporary 5-10 second pulse like effect which had this impact. Ideally globally rather than region specific effects so maybe like you say a core related but whether that effect was a ripple which moved across the Earth or all at once I hadn't decided yet.

I didn't plan on explaining the reasons behind the disaster instead leaving it to the reader to determin what must have happened, just more that this type of effect could be plausible in to happen in the first place.



 

Offline Blame

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Re: Could Earth temporarily lose its gravitational field?
« Reply #3 on: 12/08/2016 06:22:55 »
OK.

Would have to be some as yet unknown effect.  If gravity was lost for 5 seconds I suppose most of the air would remain.

Earthquakes wouldn't leave many survivors. Think how pressured the rock is a few miles down. It is not particularly elastic but there has to be compression. Can't see how releasing that tension will result in a sudden expansion of less than hundreds of meters.   
 

Offline Semaphore

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Re: Could Earth temporarily lose its gravitational field?
« Reply #4 on: 13/08/2016 21:35:11 »
Dark energy is supposed to be a repulsive gravity field, so you could imagine that some highly advanced aliens could have invented a machine to produce that effect locally.
 

Offline PmbPhy

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Re: Temporarily loss of gravity on Earth
« Reply #5 on: 13/08/2016 23:06:03 »
Quote from: Blame
To get the effect you want would require something highly theoretical and controversial.
It's neither merely theoretical nor controversial at this point. As stated above dark energy is a result of gravitational repulsion, i.e. anti-gravity. Anti-gravity can be accomplished using the general theory of relativity if one has the ability to create and control negative pressure. See: https://en.wikipedia.org/wiki/Anti-gravity

 
 

Offline Blame

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Re: Temporarily loss of gravity on Earth
« Reply #6 on: 14/08/2016 04:27:43 »

It's neither merely theoretical nor controversial at this point. As stated above dark energy is a result of gravitational repulsion, i.e. anti-gravity. Anti-gravity can be accomplished using the general theory of relativity if one has the ability to create and control negative pressure. See: https://en.wikipedia.org/wiki/Anti-gravity

Um. That link does little to strengthen your argument. Dark energy is NOT the result of gravitation repulsion. It might be the cause of a repulsion but not a result. Catch is it apparently repels space and not mass. In fact, the theories give it mass (E=MC2 transforms to M=E/C2 so energy has mass). It delivers positive gravity just like anything else with mass/energy.

 Right now Dark energy is no more than the item missing for models of the expanding universe to fit the evidence. Anything else it does, or can be made to do is speculative. 
« Last Edit: 14/08/2016 04:53:21 by Blame »
 

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Re: Temporarily loss of gravity on Earth
« Reply #6 on: 14/08/2016 04:27:43 »

 

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