Neutron stars may be bigger than expected, measurement of lead nucleus suggests

Re:Neutron stars may be bigger than expected, measurement of... by btilly on Tuesday April 27, 2021 @05:15PM (#26961662)

It depends on the size of the black hole. One with the mass of the Sun would rip your head from our feet under a tidal force of thousands of gravities. One the size of the monster at the heart of our galaxy has tidal forces so gentle that you wouldn't even notice them until after you were inside the event horizon.

If this seems non-intuitive, remember that the Schwarzschild radius varies linearly with mass, and tidal forces scale like mass / radius^3. So tidal forces at the event horizon scale like 1/mass^2. A black hole that is 100 million times heavier will have tidal forces that are 10 quadrillion times smaller at its event horizon.

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Re:Neutron stars may be bigger than expected, measurement of... by gus_massa on Tuesday April 27, 2021 @07:23PM (#26963335)

You are correct.

But the "no-hair theorem" that says that a black hole can be characterized using only 3 properties does not apply instantly, but only after some time of isolation.

For a small black hole the time is very short, but for a huge black hole that will not tear you apart it takes a long time. So even a classic huge black hole has more internal state that should be measurable from outside.

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