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To me, neutron stars are one of the most awe-inspiring astronomical objects. However...

> "Al dente"

> "Previously, scientists didn’t know how large a mountain nuclear pasta could support."

This must be one of the most pop-sci articles I've ever seen.

Seriously, I thought I must've been misreading it serveral times lol. Not sure what the target audience is here, but regardless, it missed that audience
The author isn't trying to be cute. Those are literally the terms the scientists use..

« These as-yet theoretical clumps are thought to be shaped like blobs, tubes or sheets, and are named after their noodle look-alikes, including gnocchi, spaghetti and lasagna. »

I don't think it's egregious at all. We use terms like "gnocchi phase", "lasagna phase", and neutron-star mountains regularly in the nuclear-matter literature, so these aren't indicative of any pop-sci "massaging" by the author.
I love this. I had absolutely no idea. Thanks for the info!
It's descriptive of the shape of the pasta! Long strands of nuclear material in quark-gluon plasma are called "spaghetti phase", sheets of material are called "lasagna phase", etc.
Naming things is a hard problem for computer programmers, but not for physicists. For them it's all fun!
It's not all fun for astrophysicists: the ApJ editors are pretty strict with trying to keep cute names out of the literature. One of my profs at grad school went through quite a bit of effort to get WIMPs as a name, publishing several posters and doing conference talks before submitting to ApJ for the first time.
WIMPs vs MACHOs is fucking hilarious.

Although, sadly, I think both have been exhausted as options for the dark matter search. Then again, there has been like 140 dark matter/energy papers this year, and I haven't read them all.

> nuclear pasta could support mountains tens of centimeters tall

I’m curious how much potential energy is stored in such a “mountain”. Tens of centimeters is massive; I’m sure the amount of energy must be enormous.

It is quite enormous, given the high density of nuetronium.

When a neutron star spins very fast, you get a pulsar, which emanates radiowaves that we can detect with radio telescopes. When these tiny mountains collapse, the moment of inertia changes and the star spins a tiny bit faster. In the radio emanations, the timing of the pulsar very suddenly shifts, and we call those "glitches".

https://arxiv.org/abs/1806.01521

Pulsars can spin very fast, and aggregate in big globular clusters, which are thought to be the remenant cores of old galaxies that were captured by our galaxy. If you convert their radio pulses to sound, the result is quite amazingly annoying. I recommend playing at full volume in the office to spread the joys of astrophysics to everyone!

My former boss worked on this cluster https://www.youtube.com/watch?v=IDx14fSCWIg

If you read the article and enjoyed the idea of immense mountains being just centimeters tall, I highly recommend a scifi novel called “Dragon’s Egg” by Robert L. Forward. He actually wrote a scientific research paper on neutron stars and turned the paper into a novel! Hard science fiction at its best and makes nuclear chemistry and physics delightfully approachable.
I really liked the idea of the book but to be honest I didn't like the story so the book was pretty disappointing.
To each his own! I found the way the author mapped human evolution into a familiar-but-different life form based on nuclear chemistry just so “far out” that it was a fun read.
"Hard" science fiction...
Yes, “hard” scifi is a sub-genre that adheres to physics as much as we know it to be true - no faster-than-light travel, for instance. Arthur C. Clarke and his 2001 series as well as Nivens and his Ringworld series would be good examples, whereas Dan Simmons and his Hyperion Cantos trilogy, while extremely well-written, wouldn’t qualify.
> Nivens and his Ringworld series would be good examples

Nivens features several not-quite-scientific features, though he does a better job than many at keeping them constrained. I still wouldn’t consider him a hard science fiction author.

I think Asimov, Arthur C. Clarke (as mentioned), and Michael Crichton are better examples of hard science fiction.
Niven has FTL all over, and lots of psychic powers type stuff to boot.
I’ll never understand the voting patterns here. The plot of Ringworld is literally predicated on a second generation FTL dive. I love the series and it’s semi-hard sci-fi, but the whole thing is predicated on a hyperdrive, and how a civilization with it would build and live differently from a vastly powerful species without it.
don't forget Peter Watts.
I just tried to make a dumb joke about this very hard material on the star.

I deserve the downvotes. I'm not even a real dad.

Seconded.

Likewise, Stephen Baxter's "Flux". (Even crazier, here the lifeforms dwell inside the neutron star, in the neutron superfluid.)

One of the coolest parts about neutron stars is their gravity is so extreme in its warping of space-time, it lenses light around it and you can see more than 50% of their surface when you view them face on.
Definitely going to show in "Science or Fiction" in next weeks SGU...
At trillions of times the mass of water, I'd have to suspect that it has its own gravity.

A one kilometer cube starts to approach earth mass, if you just ballpark values based on the orders of magnitude relative to water.

IIRC a sphere of neutronium about 150M in diameter is equivalent to the mass of the Earth.

Of course, if you had one of those spheres it'd blow up in your face and ruin your day. Probably wreck a bunch of the solar system, too.

Every object has its own gravity, no matter the shape or size[0]. This is taken advantage of in sensitive experiments that measure the gravitational attraction between human-scale objects[1]. The experiments are done to determine Newton's constant, G, the constant governing the strength of gravity.

[0] Even massless particles like photons have gravity, as it's actually energy that bends space and not rest mass.

[1] https://en.wikipedia.org/wiki/Cavendish_experiment

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Wow dude. That's like really helpful.

Objects have gravity. Wow. Something else.

If you weren't here, in this thread, right now, to sound the alarm, we'd all be lost.

Thank you for your service. Incredible.

Wow, citations too! You're special.

Objects have gravity. A thread about neutron stars, and you came in here to tell us that. Incredible.

Note that demonstrating gravitational attraction with an apparatus similar to Cavendish's doesn't need to be nearly as precise or delicate - the hard part wasn't showing gravitational attraction, it was measuring it so that the mass of the Earth (and thus other celestial bodies) could be determined. The simpler form of the experiment that merely shows that bodies attract one another can be done in your living room (modulo pets and children). Several of the anti-Flat-Earth YouTubers have done it, the point being to enable flattards to do it for themselves (should they be so inclined) so they're not relying on reptoid NASA Illuminati shills and their propaganda.
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?

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.

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.

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

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.
See, the pastafarians weren't crazy at all. They just believed in a version of string theory that was before its time.
Could such “pasta” exist on its own? I always thought these exotic materials depended on neutron stars’ immense gravity and pressure to keep from blowing apart.
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 no, nuclear pasta does not exist anywhere in the universe outside of a ~100m band inside neutron stars.
perfect place to get materials for my hammer
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