From my understanding Gravity is a curvature in space-time caused by mass. basically a massive object makes a dent in space and the curvature of that dent is relative to the size of the object vs. its mass(red giant vs black hole). A smaller but more massive object will make a deeper dent. But, if gravity is only a curvature of space-time and not a force, why is it so often decsribed as a force? Why would physicist be looking for a force carrier/ particle for gravity?