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Nuclear pasta in neutron stars may be the strongest material in the universe

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Re: Nuclear pasta in neutron stars may be the strongest material in the universe

#41

Post by andrepd »

warent wrote: post #19
time-of-flight wrote: post #10

Earlier quoted context omitted.

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.

Re: Nuclear pasta in neutron stars may be the strongest material in the universe

#42

Post by db48x »

kilroy123 wrote: post #40
andrepd wrote: post #36

Earlier quoted context omitted.

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.

Re: Nuclear pasta in neutron stars may be the strongest material in the universe

#43

Post by xabuq »

whatshisface wrote: post #23
beesKneesMan wrote: post #15

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.

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] h…

Wow, citations too! You're special.

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

Re: Nuclear pasta in neutron stars may be the strongest material in the universe

#44

Post by andrepd »

kilroy123 wrote: post #40
andrepd wrote: post #36

Earlier quoted context omitted.

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 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.

Re: Nuclear pasta in neutron stars may be the strongest material in the universe

#45

Post by greglindahl »

tomjakubowski wrote: post #28
time-of-flight wrote: post #10

Earlier quoted context omitted.

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.

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.

Re: Nuclear pasta in neutron stars may be the strongest material in the universe

#46

Post by gattr »

ericfrenkiel wrote: post #4

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.

Seconded.

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

Re: Nuclear pasta in neutron stars may be the strongest material in the universe

#47

Post by onetimemanytime »

kilroy123 wrote: post #40
andrepd wrote: post #36

Earlier quoted context omitted.

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

Re: Nuclear pasta in neutron stars may be the strongest material in the universe

#48

Post by sbmassey »

ericfrenkiel wrote: post #30
BurningFrog wrote: post #17

Earlier quoted context omitted.

"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.

Niven has FTL all over, and lots of psychic powers type stuff to boot.

Re: Nuclear pasta in neutron stars may be the strongest material in the universe

#49

Post by DiabloD3 »

greglindahl wrote: post #45
tomjakubowski wrote: post #28

Earlier quoted context omitted.

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.

Re: Nuclear pasta in neutron stars may be the strongest material in the universe

#50

Post by stan_rogers »

whatshisface wrote: post #23
beesKneesMan wrote: post #15

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.

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] h…

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.
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