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Wouldn't physically accurate turn your entire screen black? I would expect it to suck in way way more light than the example shows.

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If this app turns the entire screen black, this probably means WebGL is not supported :)

Black holes don't really "suck in" light. Whatever falls onto the black hole itself gets deleted, of course – but otherwise, it bends light rays towards its center. That's why the app shows distortion + black circle in the in middle in the camera mode.

The event horizon for even the smallest black hole is in the scale of kilometers. If the user is a meter away from the black hole light isn't going to move away from the center of it to your camera.

Now I think I see what you meant. There actually are no upper/lower limits on the black hole size (in classical physics – ignoring quantum effects). Compressing the Earth to ~1 cm in size would give you a black hole, and its event horizon size would be ~1 cm, not kilometers. And even black holes this small are stable, according to our physics knowledge.

This is recent conjecture?

I grew up with micro black holes being a possibility, with conjectures such as primordial black hole evaporating down to Planck dimension stability, etc.

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