Gravity- it’s known as the “weakest fundamental force”, but we know the “attraction” is really just objects falling along the curvature of space toward a more massive object. I don’t understand how this explanation of gravity relates to the other fundamental forces.
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The problem is that we do not know as a fact that gravity works as General Relativity describes, it could be that this is a remarkably good analogy and that the true mechanism acting at the quantum level manifests itself to us in this analagous form that is accurate enough for almost all purposes (except explaining things that we need dark matter and dark energy for)
We don’t know. There is still a lot of debate on the topic. There are some who still think they’ll find the mechanism for gravity that will align with the other forces: electromagnetism, the weak force, and the strong force.
There are many others that think it’s exactly as Einstein predicts.
In the end we treat it as a force, like the other forces, because in everyday life it acts like a force.
I often equate it to being similar to the Earth being a spheroid. While it is, in everyday life we treat it as flat. We know it’s not, but for most practical purposes it is. There are segments of our world that treat the world as it is, but you and I driving to the store don’t really care that it’s not flat.
Same with gravity, it may not be a “force” but it acts that way and for our everyday uses, it’s useful to treat it as a force.
Forces make things move. Gravity makes things move. Our description and understanding of how and why this occurs of it differs from the other forces like magnetism.
>I don’t understand how this explanation of gravity relates to the other fundamental forces.
without a theory of quantum gravity it won’t relate to the other forces but it’s only an issue of knowledge. i.e. we know what a photon is, we don’t know what a graviton is (or if there even *is* one, maybe it’s just a field, maybe spacetime itself is a particle or a field or something we haven’t dealt with before.)
experiments at the LHC will help to flesh out the issues:
https://home.cern/science/physics/extra-dimensions-gravitons-and-tiny-black-holes
>Some theorists suggest that a particle called the “graviton” is associated with gravity in the same way as the photon is associated with the electromagnetic force.
It’s described as a force, because it’s a good approximation.
In science, we keep it simple unless you need the better math/physics. I say “better” and not “real” because everything is a model that makes predictions.
If you aren’t messing with black holes, neutron stars, or gps (did i miss one?) you don’t need general relativity.
TLDR: “force” is good enough most of the time.
The force of gravity is what causes bodies to slide along and follow the curvature of spacetime.
The same way a difference in pressure causes net forces (and therefore motion) on objects in a fluid and a difference in voltage is what causes electrons to flow in a circuit.
newtonian gravity is sufficient in explaining most small scale phenomena we encounter every day.
It also probably doesn’t exist. Einstein is more right.
Because in our day to day life and even up to high level physics (either really really huge or really really small scale), it works just fine to think of it as a force.
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