Inside a galaxy, the curvature of space time is different in different places. This gives rise to what we think of as the gravitational field. So when you're talking about the space time curvature within a galaxy, youneed to separately treat every star and planet icause they're all sources for it.
Welcome to the October 2021 Ask Me Anything episode of Mindscape! These monthly excursions are funded by Patreon supporters (who are also the ones asking the questions). I take the large number of questions asked by Patreons, whittle them down to a more manageable size — based primarily on whether I have anything interesting to say about them, not whether the questions themselves are good — and sometimes group them together if they are about a similar topic. Enjoy!
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