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Frictionless Superfluid Found In Neutron Star Core
intellitech writes "NASA's Chandra X-ray Observatory has discovered the first direct evidence for a superfluid, a bizarre, friction-free state of matter, at the core of a neutron star (abstract). Superfluids created in laboratories on Earth exhibit remarkable properties, such as the ability to climb upward and escape airtight containers. The finding has important implications for understanding nuclear interactions in matter at the highest known densities."
Last time I got close enough to a neutron star to confirm this theory, the tidal forces nearly killed me, despite being in a General Products #2 hull.
B. Shaeffer
For all intensive purposes the universe is a perpetual motion machine. Yah enthalpy and all that will eventually slow down everything, but we wont be around to see it.
Violence is the last refuge of the incompetent. -- Isaac Asimov
Actually, it is. Remember, it takes a photon emitted by a fusion reaction reaction at the suns core tens of thousands of years to make its way to the surface of the sun, because it is reabsorbed and re-emitted so often. The fact that Cas A can be of a uniform temperature and that the temperature can change so rapidly is pretty good "direct" evidence for a superfluid. Besides, a neutron star is essentially one giant molecule anyways, since in degenerate matter protons, neutrons and electrons are pretty much in direct contact, without any "atomic" or "molecular" structure.
No folly is more costly than the folly of intolerant idealism. - Winston Churchill
For all intents and purposes, you don't know what "perpetual" means, either.
No folly is more costly than the folly of intolerant idealism. - Winston Churchill
Now, if you can put this stuff in a seamless glass sphere, and it still leaks out, I'll be impressed.
Normal helium can leak out of a seamless glass sphere, so I imagine you'd see supercooled helium leaking out as well from the same mechanism. Not that exciting, but gives you an idea of how hard some things are.
Yea except a gram of it will weigh a few million pounds.
Yeah, I happend to find unicorns at the center of that same star. My current theory is that the fluid they discovered is actually unicorn urine.
I'm trying really hard to not make a KY joke out of this.
Dude, it's astrophysics ... to the layman, it all sounds like it's a stretch.
I'm told the cosmologists are even more vague (with apologies to any cosmologists ;-)
Lost at C:>. Found at C.
I believe, what their saying is that, a superfluid can escape a container that air can not. Not that the superfluid can escape an inescapable container.
So, we should hold off on naming it 'Houdinium'?
Leave a bottle of vegetable oil somewhere (back of an upper cabinet is excellent) for a long time (year or 2) without disturbing it.
When you finally do disturb it, you are likely to find that its exterior is sticky, and that it may be puddling around the base of the container.
Oil can climb, and it can get through seals you thought were tight. All it takes is thermo- and electro-dynamics.
Quantum-fluid frictionlessness not required.
...seems like a stretch.
The gravity gradient will do that to you if you look close enough. ;)
Rampant carbon sequestration destroyed the Dinosaurs' tropical paradise. I'm here to help repair the damage.
For all INTENTS and purposes it's not, but since those purposes (if you're looking at supra-galactic time scales) aren't particularly intensive... I guess GP is right. :(
Rampant carbon sequestration destroyed the Dinosaurs' tropical paradise. I'm here to help repair the damage.
Yep, pretty much. Practically speaking, it's one of the things that keeps a helium-based Stirling engine from being one of the most efficient methods of solar power production - the stuff leaks out at every opportunity.
Yep, that's how it goes.
:( )
Although I was disappointed to find that the "climbs the walls of the container" thing was actually just in a one-atom-thick layer. (At such scales, surface tension beats gravity, and with no viscosity to hold it in check, the fluid flows up the sides molecule-by-molecule. It looks like it's just dripping through a hole in the container.
Rampant carbon sequestration destroyed the Dinosaurs' tropical paradise. I'm here to help repair the damage.
The energy is leaving the star via neutrino emission, which in turn is a result of the neutron superfluid inside the neutron star. That's the important discovery.
This is very interesting physics, because there is no way to produce these conditions in the lab, or anywhere outside a neutron star.
Of course you could just read the abstract and get all this information yourself, but this is Slashdot so knoledge takes a back seat to bad jokes and uninformed opinion.
Why is Snark Required?
Sorry about that. I am a chemical engineer, so I tend to think of specific entropy as the only type worth discussing. Of course, generally entropy is an extensive property.
No, it doesn't. It's at ~0K and once it hits that point the atoms become essentially still, aligning and allowing it to pass through the solid container. As Pratchett says: "Because of Quantum". Whilst that video is a short clip, if you watch the recent BBC Horizon episode - "What is one degree?" (I believe it was that episode). Unfortunately I don't know the quantum theory of superfluids to explain this any further but that is my understanding of it. Atomic alignment allowing one thing to pass another.
Besides, a neutron star is essentially one giant molecule anyways, since in degenerate matter protons, neutrons and electrons are pretty much in direct contact, without any "atomic" or "molecular" structure.
Respectfully, this isn't correct. The core of a neutron star is indeed degenerate matter, but it's exclusively neutron degenerate matter, with a complete lack of protons or electrons. Every particle is a neutron, with no space at all in between them. Calling it a giant molecule is not accurate in any interpretation I can think of. I have heard of neutron star cores described as one giant atomic nucleus, which is slightly more accurate (in that it's made of subatomic particles in direct contact with each other), though actual nuclei are held together by nuclear force instead of gravity.
Now, the outer layers of a neutron star are made of electron degenerate matter with a thin surface of highly compressed regular matter. That fact may have been where you got the "protons, neutrons and electrons" part of your post - there are no protons or electrons in the interior, but they are present in the outer layers. Which, while interesting, doesn't really matter in regards to TFA, as they observed evidence of a superfluid core, and the core is nothing but neutrons.
Erotic is when you use a feather. Exotic is when you use the whole chicken.