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Comment by Etheryte | Hacker News Reader

The ocean is host to a very wide number of creatures and bacteria, some live in arctic cold waters, others on volcanic vents, and every range in between. There's a good saying for this, roughly translated, that nature doesn't love an empty spot — if one type of plant or bacteria won't live in an area, someone else will quickly settle in.

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We have "nature abhors a vacuum" in English

I think these quotes are coming from either end of the spectrum of physics and biology and don't necessarily say the same thing.

The beauty of the phrase is that it’s universal.

Is it?

I want to talk with aliens as much as the next guy, but so far it seems like the vast majority of the universe is a vacuum--biologically speaking.

Physically too. But it's a question of perspective: glass half-empty or half-full. Are planetary systems plentiful? It seems so, as a ratio of all star systems - as far as we know at least. Definitely not, as a ratio of the total volume of space. Similarly, the idea that we are mostly vacuum, because the elementary particles are so small compared to the size of molecules, etc. But that doesn't much change our intuitions about solidity vs. emptiness in every day life.

The way I see it, space is a life-vacuum, and human nature is to abhor that, as evidenced by the long-standing goal we have of interplanetary/intergalactic settlements.

Which is to say: you’re thinking on the wrong timescale. Just wait and see. :)

That's because there is not much stuff in the universe, and whatever there is, tends to cluster together under gravity. But within such a cluster, if you create empty space, something will want to rush to fill it in.

No one ever said the vacuum has to be filled biologically. The universe is a vacuum but even there you get spontaneous virtual particles getting created out of nothing as far as we know.

Virtual particles aren't particles, and don't get created out of nothing. They're a mathematical trick to simplify (read: make tractable) physics in a particular formalism.

Apart from being drawn as particles on diagrams, they violate every rule of what a particle is supposed to be.

There are formalisms where they aren't necessary, for example quantum lattice models.

Anyone hearing one abhors a vacuum; in fact they are designed to amplify certain sounds, such as dust particles passing through the system. Consumers equate "loud" with "powerful" and this improves sales and product opinions. Yes, I'm aware this is a different kind of vacuum.

We have a new phrase, “Gravity abhors a vacuum.”

In a post-Dyson world, many vacuums rely on gravity to work.

I think that's inertia.

I am familiar with that sentiment expressed through the phrase "nature abhors a vacuum"

The irony is that this phrase predates the Torricelli experiment, in which he used a glass vial and mercury to produce a vacuum, and the eventual discovery that the vast majority of nature is a vacuum (outside of the atmosphere of planets and stars).

And if it wasn‘t for gravity, everything inside the atmosphere of planets and stars would be rushing to fill that vacuum. Nature abhors a vacuum, but that‘s only tempered by the fact that there are more powerful forces than vacuums.

That's not quite right. Even if there were no gravity or other forces, there would be no incentive for matter to go in one direction vs another, regardless of the distribution of matter around it. Over time you'd get a uniform-ish distribution, but that's a question of statistical mechanics, not one of pressure differences.

On earth, matter only rushes to fill vacuums because the surrounding air or water pressure pushes it in.

Vacuum doesn’t necessarily mean pressure-vacuum. It roughly means extreme concentration gradient, which is as you’ve described universal.

> but that's a question of statistical mechanics, not one of pressure differences.

My limited understanding was that 'pressure' is just a simplified way of speaking about statistical mechanics.

If all of the matter in the universe were evenly distributed, it would be so close to a vaccum as to make no difference.

Don't forget, even within individual atoms, the overwhelming majority of the space is a vacuum.

It also predates attempts to use dewatering pumps in mines, leading to the snarky variant “nature abhors a vacuum, but only up to 32 feet.”

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