Helium White Dwarf Stars Bear New Quasiparticle 28
eldavojohn writes "Helium white dwarf stars are now theorized to produce a new kind of quasiparticle that would explain a known temperature anomaly between helium white dwarfs and vanilla white dwarfs (lumps of charcoal). Since helium can form a Bose-Einstein condensate and there are extra constraints inside such a dense object, a new quasiparticle emerges. Researchers' models claim it 'reduces the specific heat of the white dwarf core by two orders of magnitude compared to a crystalline core.' But even with that figured in, measurements of some nearby ancient helium white dwarfs show that they don't fit the specific temperature curve exactly. So, some questions remain, with the possible explanation that these stars undergo internal transition late in their age. The heavy reading is available on the prepublication site arXiv."
First quasiparticle post (Score:1)
Look how cool it is B-)
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Sorry, no, I can't see it. Not even Hubble can see it.
Anyone else get the feeling (Score:1)
that when Physicist can't explain anything these days, they just invent a particle for it?
Re:Anyone else get the feeling (Score:4, Interesting)
Not really. The group is basically extrapolating the known behaviour of Bose-Einstein condensates (known to form from helium) in the conditions that may be present inside a helium white dwarf. The fact that you think they're just throwing their hands in the air and making things up out of whole cloth I find rather disturbing.
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The fact that you think they're just throwing their hands in the air and making things up out of whole cloth I find rather disturbing.
Well, I do find that there's a lot of "we don't know, so lets just invent a particle" happening too. It often works, is the thing. Neutrinos were invented to make the books balance long before they were explained, for example. And don't get me started on "inflatons", sheesh.
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Yes - and that reminds ME of epicycles. Mathematical constructs that could be used to make predictions - they 'worked' but were the result of astronomers looking at the universe from the wrong perspective... *grin* I'm not QUITE arrogant enough to claim I have the right perspective though. Well, not in public, and not before at LEAST 6 beers, anyway...
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I think there are damn few particle physisists who actually like the Standard Model. It's epiccyles on top of epicycles, and completely inelegant. But still, no better theory has emerged, no doubt in part all those years wasted on string theory at the expense of competing ideas.
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That does rather point to the predictive ability of the models they're using, now doesn't it. :)
Often, when someone 'invents' a new particle, they're not really inventing anything, but rather taking existing models and examining them for solutions that match or can explain their observations. Trying to shoehorn in something completely new, while it might explain the new observation, could very easily make a mess of everything else, which wouldn't make a terribly good extension to a theory. :)
And bear in mi
Re:Anyone else get the feeling (Score:5, Insightful)
that when Physicist can't explain anything these days, they just invent a particle for it?
I rather suspect that when an AC can't understand something in physics or some other scientific field, and the arguments and evidence on the matter are incomprehensible to him, he tries to project his ignorance onto those who do understand the issue. Yet another manifestation of the Kruger-Dunning [wikimedia.org] effect.
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Hmmm. Sounds like you are pretty certain that that's common for ACs... *chuckle*
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Re:Anyone else get the feeling (Score:5, Informative)
There's a reason they're calling it a "quasiparticle". A quasiparticle is an effective particle that arises when you perturb a quantum system - they're effectively the quantum analogues of sound waves. Depending on the type of system, you can get various types of quasiparticle. The most basic would be phonons, which are literally quantised sound waves, and which I imagine would crop up in any system (but I'm not a condensed matter physicist and haven't touched it in ten years so there may be systems possible where phonons don't arise and I wouldn't know). In some quantum fluids you can get things called rotons forming, which you could view as kind of quantised vortices. In more complicated systems again you get quasiparticles emerging with all manner of weird and wonderful behaviours, and about ten years back Volovik showed something beautiful, which is that if you take a particular state of superfluid Helium the quasiparticles that emerge have all the symmetries of the standard model of particle physics *and a graviton*. Which is really extremely beautiful when you think about it.
Anyway, those are quasiparticles: well-defined quantum fluctuations of a system.
The particles you're referring to are from speculative high-energy physics, and are on much shakier ground, as the physicists who propose them would readily admit. Those particles are generally "real" in a sense that quasiparticles aren't (although I wouldn't stretch the term "real" too far even for something like virtual photons or gluons or other gauge bosons; even so, the fundamental nature of the particle is very different to the quasiparticle).
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that when Physicist can't explain anything these days, they just invent a particle for it?
You're confusing physicists with Star Trek writers.
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I have an Idea Captian!!!!! (Score:1)
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Of course, like using smoke in a wind tunnel!
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Voltaire
Headline (Score:5, Funny)
White Dwarf Stars Bear
is that like
Red Dwarf Stars Cat
Is Chris Barrie (Rimmer) in it too?
Cooling rates (Score:2, Interesting)
White dwarf cooling rates impose interesting constraints on physics beyond the standard model. A change in the phase diagram for stellar cores may have interesting effects on what we know about dark matter and dark energy.
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No it would be nothing like either. There are no chemical bonds, just a plasma of electrons and nuclei.
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Wouldn't the heat keeping the electrons and nucleii apart eventually escape from the system?
It seems like a perpetual motion machine that mass can create gravity, gravity causes pressure, and pressure creates heat.
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The fundamental paradox there was rescued by quantum mechanics. the Pauli Exclusion Principle applies to the electrons, so even at 0 temperature they can't all occupy the ground state. And the uncertainty principle says that since there's such a large numbers of electrons all in a small space they are quite localized and hence must have high momentum.
It's a state of matter known as electron degeneracy: http://en.wikipedia.org/wiki/Degenerate_matter [wikipedia.org]
BEC Temperature/Pressure? (Score:2)
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Pretty much. It's achieved with a pressure/density that's far beyond anything achievable on earth.
that's sooooo politically incorrect. (Score:1)
The proper term is Little Stars.
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