John Carlos Baez on Nostr: - yes, it's obvious! I explained the basic idea in a recent post here, but it's easy ...

- yes, it's obvious! I explained the basic idea in a recent post here, but it's easy to overlook these posts:

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"Right before you hit the horizon, you will see your body turned into a razor blade and your nose will get red-shifted."

This is wrong. By taking a sufficiently large black hole, the spacetime curvature near the horizon can be made arbitrarily low, so nothing funny will happen to you *locally*. This is called "the equivalence principle" and it's an easy way to solve lots of problems in general relativity, but only problems that are local in space and in time.

We can even bring in some numbers to guess what "sufficient large" mean:

As I mentioned in an earlier post, people know from observation that Sun-sized stars get ripped to shreds before crossing the event horizon of a black hole of mass < 10⁸, but not for a more massive black hole (of which there are plenty). Since you're a lot smaller than the Sun, you could easily fall into a 10⁸ solar mass black hole in your spaceship and not notice *at all* when you cross the horizon, if you don't look out the window!

So, if you think something weird happens like "you'll see your body turn into a razor blade", you haven't internalized the equivalence principle.