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2026-08-25 18:57:48 UTC
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Bartosz Milewski on Nostr: I couldn't resist some back of the envelope calculations. Schwarszchield radius: \[r ...

I couldn't resist some back of the envelope calculations.
Schwarszchield radius: \[r = \frac{2GM}{c^2}\]
Newton's gravitational acceleration:
\[a = \frac{GM}{r^2}\]
Acceleration at the horizon:
\[a = \frac{GMc^4}{4G^2M^2} = \frac{c^4}{4GM}\]
Just looking at orders of magniture: \(c = 10^8\), \(G-10^{-11}\), \(M = 10^{41}\) gives the approximation \(a=10^2\), which is close enough.