Physics, Astronomy & Cosmology / Re: What happens to the spacetime interval between two events as they approach a BH?« on: 20/02/2021 16:19:26 »
Is it fair or noteworthy to say all these events in GR are treated as point objects even though they are actually spatio-temporally extensive?Events are by definition mathematical points in spacetime, say the event of a photon being emitted and such. In practice, yes, they're spread out, so one can speak of the event of the sinking of the Titanic even though the ship is fairly large and moved around quite a distance during the hours-long process. It just means we lose precision when we talk about that event.
Billiard balls are modeled as point events (the event of the contact between two balls) when in fact the contact takes finite time, involves finite (but very large) acceleration, and finite surface area of contact.
Is that where a theory of quantum gravity might be useful?It's just geometry. No, quantum gravity solves other issues.
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