B What Causes Mass to Exert Gravitational Pull?

Palasta
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Greetings. I registered to this forum because of a particular issue regarding Gravity. I'm no astrophysicist or mathematician, i searched to find an answer, but the terminology and equations are a little much for me. I feel the best direct way is to ask people with the right expertise.

It is unknown what exactly causes mass to have a gravitational pull, right? Illustrations of Mass, Gravity and SpaceTime show e.g. a planet sitting in a gravity well, spacetime curving around it. Demonstrated in the video with marbles (mass) on a sheet of fabric (spacetime/gravity).



Mass and SpaceTime two unconnected entities so to say. What is on my mind, is Spacetime as "unbroken" canvas. Not warped around objects, but permeating matter, where it is folded, curled, compressed or whatever within the atomic structure, the mass is defined by the entraped "spacetime-energy", which is contracted and pulls in neighbouring "massless" spacetime, thus creating the phenomenon gravity. A 3D background grid.

Now i want to know if this was already considered and scraped because of various apparent problems. For example would this still require a carrier particle?

I have more on my mind, but i think that's not needed.
 
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Palasta said:
It is unknown what exactly causes mass to have a gravitational pull, right?
Wrong. Mass (or more generally stress-energy) causes spacetime curvature, and what you call "gravitational pull" is a manifestation of spacetime curvature.

Palasta said:
Demonstrated in the video with marbles (mass) on a sheet of fabric (spacetime/gravity)
This is a common pop science representation but it is seriously flawed. We have had a number of previous PF threads on this.

Palasta said:
What is on my mind, is Spacetime as "unbroken" canvas. Not warped around objects, but permeating matter, where it is folded, curled, compressed or whatever within the atomic structure, the mass is defined by the entraped "spacetime-energy", which is contracted and pulls in neighbouring "massless" spacetime, thus creating the phenomenon gravity. A 3D background grid.
All of this is too vague to even respond to (and please note that PF has rules forbidding discussion of personal speculation, which you are skirting the edge of here). You would be much better served by taking the time to learn what our best current theory of gravity, General Relativity, actually says, not from pop science videos but from actual textbooks or peer-reviewed papers. Sean Carroll's online lecture notes on GR are free and are one good place to start.
 
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