Wikipedia points out that Gravity is:

most accurately described by the general theory of relativity (proposed by Albert Einstein in 1915) which describes gravity not as a force, but as a consequence of the curvature of spacetime caused by the uneven distribution of mass.

As I am not all that clued up on physics, I don't quite understand this and to add to the confusion, in the top voted answer to the closed question, What is Gravity?, the answer starts of by saying that

Gravity is a fundamental force in addition to the other 3 known forces of nature that are: electromagnetism, the weak force and the strong force.

then later on states that

Einstein's theory treats gravity as something other than force, namely that it isn't a force.

so I have been trying to understand it all with a bit more reading.

In the question, What is Gravity and what causes objects to act against it?, there is a passage with an image which if I understand it correctly, explains the quote from Wikipedia.

So I understand the concept of gravity, in that it's not actually a force, but more of a displacement in the spacetime grid. An object with a big enough mass will bend the spacetime, causing smaller objects to "attract" to it Earth in its spacetime

So the fact that the Earth, the moon and other planets are spinning is not what creates Gravity somehow? Is the bent spacetime why they do not act like a centrifuge and throw everything off the surface?

To add to this, a few years after Einstein’s theory of relativity described gravity as the distortion of space and time, we gained awareness of the confusing world of quantum physics. This led to the discovery of force-carrier particles, or bosons, behind three of the fundamental forces. This is all totally outside my comprehension, and in an attempt to marry gravity with quantum theory, physicists came up with a hypothetical particle — the graviton, and the name is attributed to Dmitrii Blokhintsev and F. M. Gal'perin in 1934.

What I am trying to understand is how is Gravity created?

With all these theories, am I to assume we actually don't know how gravity is created, even though it was discovered in the 17th century and we have had over 400 years to find out?


To avoid confusion you should not mix up the Newton's theory of gravitation and Einstein's general relativity.

According to Newton gravity is a force which is measured as attractive between massive objects. As per Newton gravity is generated by the mass.

However Einstein via the equivalence principle understood that the trajectory of a free falling object in spacetime is independent of its mass, so gravity could be described as a geometry shaped by the distribution of mass/energy in spacetime. A free falling object follows a geodesic and experiences no acceleration; instead an object stationary on the earth surface is subject to acceleration which deviates it from a geodesic. This acceleration in Newton theory is interpreted as the force of gravity. The spinning earth does act as a centrifuge, but the centrifugal force, luckily for us, is negligible compared to the force of gravity.

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    $\begingroup$ This doesn't seem to answer the question. The OP knows that gravity overcomes the centrifugal force, but he is wondering how the gravity is created. "As per Newton gravity is generated by the mass." - How? $\endgroup$ – Chalmondley Mar 20 at 8:35
  • $\begingroup$ Physics describes how nature works, not why nature works in that way. Your question is not applicable in science. $\endgroup$ – Michele Grosso Mar 20 at 16:23
  • $\begingroup$ You said, "Physics describes how nature works, not why..." I have asked how gravity works. As @Chalmondley says, you haven't said how. You just said it is generated by the mass. How? $\endgroup$ – Chris Rogers Mar 21 at 8:26
  • $\begingroup$ We have to be careful with the phrasing. Science measures relations between physical variables (observables) and then infer physical laws to be validated in successive experiments. Experimentally two bodies attract each other with a force directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers (Newton's law of universal gravitation). That is how things work in nature. Science can not say more, just describe it. A refined description is the general theory of relativity. $\endgroup$ – Michele Grosso Mar 21 at 10:36

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