A gauge symmetry is just a re dency of description. It's like coordinate in variance, right? You're always allowed to choose whatever coordinates you want. Special relativity only tells you about inertial or straight line, unaccelerated particles. So physics looks simpler in those co ordinate systems in special relativity.
Welcome to the November 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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