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Comment by RealityVoid | Hacker News Reader

The water level decreases, along with the shore and anything with it falling within the event horizon. Any other apocalyptic brain teasers?

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The intake rate of a microscopic black hole is too small to measurably absorb much matter before it falls through to the bottom of the lake until it reaches the center of the planet and oscillates there.

The more pressing thing is that every thing around the lake is irradiated by the evaporation of the microscopic black hole, which supposedly emits quite a lot of energy, as it falls through the bottom.

According to wikipedia, microscopic is considered up to 1 micron. [1] According to the Schwartzchild formula [2] r=(2Gm)/(c^2) so if I take the largest black hole the definition would allow, the mass would be about 10% of the moon. You'd feel 1G at about 60km distance because of it. But indeed, it would fall and take about 20 minutes to reach the core of the planet, while displacing a whooping 1gram of matter. Kind of funny how wierd this whole thing is.

[1] https://en.wikipedia.org/wiki/Microscopic_scale

[2] https://en.wikipedia.org/wiki/Schwarzschild_radius

You drop a bowling ball off a space boat into a black hole. Has the amount of mass inside the universe increased, decreased, or stayed the same, ignoring the effects of all other changes?

The amount of mass inside the universe has stayed the same, it just moved from the boat into the black hole.

You're really bored at work one day so to entertain yourself you create 1kg of antimatter along with 1kg of matter. Has the mass in the universe increased or stayed the same?

The mass of the observable universe has probably changed a lot by the time the bowling ball hits the bottom.

You drop a black hole the size of a bowling ball into a frontier AI startup.

At what point does NVIDIA give you $200bn?

At the point nvidia's office becomes part of the accretion disk.

I'm not sure what other effects I should ignore, but the mass would increase. The ball gains relativistic mass as it accelerates towards the black hole.

PS: Assuming the boat isn't falling too (it's still in orbit), dropping the ball does nothing. You need to decelerate it (reduce it's orbital speed) for it to fall into the black hole.

I think a microscopic black hole would evaporate very quickly from Hawking radiation, so the result might be more bang than suck.

Sure, but the mass is not specified so I just assumed the closest one to cosmic horror.

You invert the phase of the Higgs field within a basketball. What happens?

The universe becomes suddenly VERY different, while a ghostly rendition of the Harlem Globetrotters theme whistles eerily in the background?

(I actually don't know the answer to this)

I believe this would nucleate a cosmic string (and annihilate everything in its vicinity obviously)

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