When considering the Newtonian forces, it's somewhat intuitive to think about the equilibration of forces, e.g. two charged particles overcoming the gravitational attraction to repel each other. Nothing new. What puzzles me though is to consider the same case within the context of GR and QED. Now gravity isn't a "force" and neither is the photon field. The gravitational acceleration is simply a trajectory through curved spacetime, and the electromagnetic force arises from the exchange of photons. So now how am I to imagine this "force" equilibrium? Does the electromagnetic energy counteract the gravitational mass energy of our two particle system in such a way that space is flat? Or is the electromagnetic "force" resisting the curvature of space? I have a hard time conceptualizing the intuitive content of classical physics within the framework of more fundamental theories.(adsbygoogle = window.adsbygoogle || []).push({});

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# Force equilibrium in GR

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