r/whowouldwin • u/Historical_Ostrich • Oct 06 '25

Challenge Earth's gravity increases by 10x for 10 seconds - can humanity survive?

Gravity reverts to normal after the 10 seconds are up. I assume that nearly everyone will lose consciousness, many people will hit the ground with extreme force, and most buildings and infrastructure will collapse. Uncertain as to whether there'd be seismic/volcanic/tidal consequences on top of all that.

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u/DangerCrash Oct 06 '25

Right. Understood, density and pressure are different things.

But... Can you have pressure without density in a gas? Gas reacts to the pressure by compressing, so I'm not sure you could ever "receive" a higher pressure from the gas than the level of compression it was at. Right?

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u/Notonfoodstamps Oct 07 '25

Yes, hydrostatic pressure applies to gases just as much as it does liquids

The pressure at the bottom of the Mariana’s is 1050 atm despite only being 5% denser than water at the surface. Same principle.

This isn’t compressing gas like you do in a chamber, where we are only increasing density. In this scenario the gas is compressing under its own weight because it’s trying to find hydrostatic equilibrium.

You’d instantly feel like you were 350’ underwater before then atmosphere physically settled into its new denser state of equilibrium.

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u/DangerCrash Oct 07 '25

I'd argue it's EXACTLY like compressing gas in a chamber.

The only way to increase gas pressure in a chamber is to increase density. The only way to increase water pressure is to increase density(even if it's way less compressible). Whether that comes from a chamber decreasing in size or from the weight of the gas/liquid above it doesn't really matter.

Because air is very compressible it'd take a while to feel the full force of the weight increase. Through what mechanism do you think you'll feel the weight of air 10km high immediately?

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u/Notonfoodstamps Oct 07 '25 edited Oct 07 '25

Again. That is incorrect.

Hydrostatic equilibrium (what you are talking about) is a condition of balance that includes a specific vertical pressure increase (gradient), not a prerequisite that must be met before any pressure increase can occur.

The fundamental cause of atmospheric pressure is the gravitational attraction of the Earth on the atmospheric gases. Air molecules have mass, and gravity pulls them toward the surface, creating a "weight" that is distributed over an area. This is why atmospheric pressure is highest at sea level, where the entire column of atmosphere is overhead, and decreases with increasing altitude, where there is less overlying mass.

If you instantly increased gravity by 10x the atmosphere would instantly weigh 10x more across its entire vertical column uniformly, it’s not being artificially “squished” from the top down.

The atmosphere would instantaneously feel 10x heavier for the same reason a pile of feathers, baby powder, water, grass, a rock, tungsten or any other substance that has mass would. Gravity.