The cause of spacetime and gravity

In summary, the conversation discusses how a large amount of mass in a small area can cause spacetime to bend towards the center of mass. The question is raised as to why only light is affected by this bending and not other moving particles. It is explained that according to Einstein's theory of general relativity, everything with mass or energy is subject to gravity, including gases. The model proposed in the conversation is actually the same model used in general relativity to explain gravity.
  • #1
victorhugo
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Does a large amount of mass in a 'small' area cause spacetime to bend inwards to the centre of mass?

If so:
Since the path of light changes because it is traveling with the bent spacetime, why wouldn't other moving particles also bend their path while moving in a bent spacetime? So if it is possible that this bend in spacetime causes particles that are always in motion (such as gases) to bend their path towards the centre of mass, causing gases to stay on Earth. So with this, instead of gravity pulling us down, it's just buoyancy/density + the curved path of spacetime directing motion towards the centre of Earth that causes what feels like gravity. With this model, we can explain simple things such as how a bicycle works and why shower curtains blow inwards.
 
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  • #3
victorhugo said:
With this model, we can explain simple things such as how a bicycle works and why shower curtains blow inwards.

Now THAT would be something!

Some of your questions strongly indicate a need for more reading and understanding before answers are attempted. Be patient, it even took an Einstein some time to understand relativity.

On the other hand, you are on the right track here:

victorhugo said:
Since the path of light changes because it is traveling with the bent spacetime, why wouldn't other moving particles also bend their path while moving in a bent spacetime?

It was a great confirmation of Einstein's ideas when observations made during an eclipse of the sun indicated light was in fact curved as it passed by the sun. Nobody was sure about that before Einstein's theory. On the other hand, it was already pretty well understood that massive particles [meaning any particles with mass] would be subject to gravity.

A key idea is that unlike the three other forces, EVERYTHING is subject to gravity: Anything with mass or energy [or pressure or even stress] follows Einstein's formulation. Even gases. Even space and time. For example, gas particles [like hydrogen atoms, for example] of the early universe coalesced due to gravity and eventually formed suns, planets, [the Earth included] and galaxies and even black holes. And we continue to observe all that happening today.
 
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  • #4
victorhugo said:
With this model, we can explain simple things such as how a bicycle works and why shower curtains blow inwards.

These things have nothing to do with GR and are off topic here. (I have moved the subthread on this to a new thread in General Physics.)

The model proposed in your OP (if we leave out the speculative analogy with buoyancy, etc.) is not a different model of gravity from GR; it is the model of gravity used in GR. In GR, what we call "gravity" is due to curved spacetime "bending" the paths of things. (This is just a quick heuristic description, of course, but it serves to get across the basic idea.) So GR already does what you propose.

Thread closed.
 

1. What is the relationship between spacetime and gravity?

The theory of general relativity states that spacetime is a four-dimensional fabric that is curved by the presence of massive objects such as planets and stars. This curvature of spacetime is what we experience as the force of gravity.

2. How was the concept of spacetime developed?

The idea of spacetime was first introduced by Albert Einstein in his theory of general relativity, published in 1915. He proposed that instead of viewing space and time as separate entities, they should be understood as interconnected and inseparable.

3. What causes spacetime to curve?

According to the theory of general relativity, the presence of massive objects such as planets and stars causes spacetime to curve. This curvature is a result of the object's mass and energy, and it determines the path of objects moving through it.

4. How does gravity affect the flow of time?

Gravity can affect the flow of time due to the curvature of spacetime. The stronger the gravitational force, the slower time moves. This phenomenon is known as gravitational time dilation and has been confirmed through experiments and observations.

5. Is there a single cause of spacetime and gravity?

Currently, there is no single cause of spacetime and gravity that has been identified. Our current understanding of these concepts is based on the theory of general relativity, but scientists are still working to develop a more comprehensive understanding and potentially uncover a unifying theory that can explain these phenomena.

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