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Comment by endymi0n | Hacker News Reader

In a true Randall Munroe "What if?" fashion, I'd be interested if this stuff would be stable enough to hold together on its own or if it needs the absolutely extreme gravity and pressure around it to stick together and would fall apart otherwise.

So if a teaspoon of Nuclear Neutron Pasta would really end up somewhere on a meadow here on Earth, what would happen?

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Nuclear pasta is a phenomenon that appears when electromagnetic repulsion and strong force are more or less on the same strength. This only happens in a relatively narrow band of (stupendously high) densities. So yes, nuclear pasta does not exist anywhere in the universe outside of a ~100m band inside neutron stars.

Source: I studied this for 2 years.

But... what _would_ happen if you instantly (and magically) transported a teaspoon of it, into a random place on earth?

It would start out under the pressure of all that gravity, and then at the instant of the teleportation the gravity would be gone. With no external force holding it together it would expand outward very rapidly.

It would behave as regular baryonic matter (i.e. plain old atoms and molecules) does at atmospheric pressure. Only it would release a spectacular amount of energy due to how much it was compressed before.

How much energy? We can make a crude estimation: a neutron star has a gravitational binding energy in the order of magnitude of a whopping 10 to the 31 megatons of TNT, and a radius of about 10km. Make a direct proportion to your desired amount of pasta.

it would break down if I understood the OP correctly. Not stable unless...

A significant amount of Earth is already made out of neutron star debris. Outside of the extremely high pressure environment it decays to ordinary atomic matter.

Boom

https://physics.stackexchange.com/questions/10052/what-would...

I mean, a really stupendously huge boom. There is no question that this stuff would be unstable outside I’d the gravity well of the neutron star, so if you could teleport it away, you’d have an incredible explosion. I’d even speculate on top of that first answer that as H was formed under the initial conditions of the explosion, you might see nuclear fusion for a brief time. Either way, it would be ugly.

One of my favorite PBS Space Time [0] videos discusses the nature of the matter of neutron stars, and although he doesn't discuss the different pasta types, he does discuss the theoretical possibilities of "strange" stars (where the some of the quarks flip to strange to get around the Pauli Exclusion Principle) and also some larger neutron stars may have an electro-weak core, an apple-sized core where the electromagnetic & weak nuclear forces have merged (similar to 1/1,000,000,000 after the big bang) with the mass of 2 earths.

[0] https://www.youtube.com/watch?v=u4RNGRyzt10

That was my first question and I was disappointed the article didn't address it. How can we call a material "strong" if it can't even hold itself together without such extraordinary help from its environment?

How can we call steel "strong" if it can't hold itself together unless cooled down to less than ~1500 °C?

It's all relative.

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