B Can We Really Stop Gravity by Altering Spacetime?

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The discussion centers around the misconception of spacetime as a fabric analogy, which is deemed misleading and overly simplistic. Participants emphasize that while mass does curve spacetime, the analogy fails to accurately represent the complexities of gravitational physics. The idea of applying a force to "flatten" spacetime and stop gravity is dismissed as impractical and based on a flawed understanding of the underlying physics. Experts clarify that the metaphor should not be used to draw conclusions about gravitational mechanics. Overall, the conversation highlights the importance of accurately interpreting spacetime concepts in physics.
Odette
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I know this is probably going to sound stupid but I'm really curious for the opinion of someone who has knowledge.
Well spacetime is like a stretched bed linen. Putting on an object with a big mass, will cause its curvature.
Now imagine having a piece of fabric holding it stretced from both sides. Place a ball on it. It will curve. Just like the spacetime by a sun etc.
If we would put a force with our hand down the fabric (where the curve is), equal with the mass of the ball, the fabric would return to its first shape. Is that even possible to happen to spacetime? Could we put a force somehow in the deformed area and bring it back to its first shape?
And if that is possible, wouldn't that mean that gravity would stop since it's caused by the curvature of spacetime?
I don't know how much stupid this sounds to you but I would appreciate it if you could expalin to me why isn't it possible
Or why it is.
Thank you:)
 
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Odette said:
I know this is probably going to sound stupid but I'm really curious for the opinion of someone who has knowledge.
Well spacetime is like a stretched bed linen.
No, it is not. This is a VERY misleading pop-science hueristic and is not to be taken as actually meaningful.

Putting on an object with a big mass, will cause its curvature.
In the heuristic, yes, but again, it's just a pop-sci presentation and misleading
Now imagine having a piece of fabric ...
You need to drop the fabric analogy. It just causes confusion.
 
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Odette said:
Well spacetime is like a stretched bed linen.
No it is not. It is a common metaphor used in popular text, but you should not in any way confuse it with what is actually going on and you should definitely not use it to make inferences about how the physics works.
 
phinds said:
No, it is not.
Orodruin said:
No it is not.
Haha. I started reading thinking ”but I did not use a comma ...”
 
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@Odette The level tag you chose (”A”) indicates that you have knowledge of the subject equivalent to a graduate student in physics or more and expect an answer and discussion on that level. Based on your question this seems not to be the case. I have changed the level tag to ”B”.
 
Orodruin said:
@Odette The level tag you chose (”A”) indicates that you have knowledge of the subject equivalent to a graduate student in physics or more and expect an answer and discussion on that level. Based on your question this seems not to be the case. I have changed the level tag to ”B”.
Ok sorry I'm new I didn't know
 

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