Where does gravity come from? How does an object's mass shape the fabric of
spacetime?

gravity comes from all its mass. All its mass makes a combined gravitational pull on all the mass in your body. That's what gives you weight.

Every object in the universe pulls on the space around it, drawing the fabric of space-time toward its center. The more massive the object, the more it pulls. ... The physicist John Wheeler captured these odd notions

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