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Comment by meisel | Hacker News Reader

I'm curious what objects do/don't survive at the water pressure. I guess bottles are strong enough

Solids and liquids mostly don’t compress so as a general rule most can handle those pressures without experiencing any real mechanical stress, as they instantly provide a perfectly matching internal pressure that balances out the forces to zero.

It’s mostly things that contain gases that can get crushed by high pressure. Almost any type of closed cell foam for example, will either collapse to a small size or crack and crumble apart depending on how rigid it is.

Living things tend to get harmed by pressure changes because they have compressible gasses and/or biological compartments that contain things that experience phase changes between gas and liquid at different pressures.

Presumably it was open & empty, so it's just a piece of glass surviving...

Even so, wouldn't you expect that you could crush an open empty beer bottle by putting a heavy enough weight on it? A human can't do it, but I would expect an elephant can.

That's not how pressure works if it's opened. The forces balance out

The pressure inside the bottle is the same as the outside. So it’s not the same as stomping on an empty bottle.

But the forces are the same all around the bottle (again assuming it is open)

The bottle wouldn't be empty though.

There is quite a lot of pressure put outside from the beer of a full bottle, but that little bit of air is probably enough to cause it to implode at some point.

I'll be honest; I have no idea how to estimate that. I'm sure there are folks on here who can (and might). It's probably not as deep as you'd think.

I'd imagine the cap will fail under the pressure long before the forces get high enough to implode the bottle.

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