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Comment Re:No comments, then a flood of experts (Score 4, Interesting) 238

Well, it's just cool because it probes new regions of the parameter space (temperature and density) of quantum chromodynamics (the fundamental theory of the strong nuclear force). Knowing what nuclear matter does under extreme conditions teaches us new things about what kinds of matter that might exist in the cores of neutron stars, whether there could be more compact kinds of stars between neutron stars and black holes and what conditions were like during the first moments after the Big Bang. It also gives us more data to compare against the predictions of quantum chromodynamics, which will help us make sure that that's actually the correct theory of the nuclear forces. I can't think of any practical applications (say, to fission cross-sections or something) off the top of my head, but that doesn't imply they don't exist.

Comment Soldered our supercomputer back together (Score 5, Interesting) 321

Back in my grad student days, we saved the early hardware for our supercomputer (a BlueGene precursor) by programming and soldering an EEPROM to every daughterboard. On a massively parallel machine, that was quite an undertaking, and given that we were all *theoretical* physicists, it was kind of a miracle that the thing worked when we were done.

Comment Re:Silica? (Score 2) 181

According to TFA, the MgSiO3 dissociates into SiO2 and MgO under Jovian core conditions. They don't calculate what happens to the SiO2, but assume that its solubility is similar to the MgO component. So that would mean that the SiO2 also goes into solution in the Jovian core.

Also of interest (at least to me) but not addressed in this paper is what happens to the nickel-iron component of the core. Perhaps they figure Jovians don't have enough to worry about, since they form so far from the center of the protoplanetary disk?

Comment Don't bet your house on this result holding up (Score 4, Interesting) 80

It's consistent with DAMA and Cogent in the sense that it's ruled out by those experiments at only a few sigma. It's "near" Cogent in the sense that 8 is "near" 25, and it's "near" DAMA in the sense that 35 is "near" 10; that is, it's not near at all. It's ruled out by Xenon by many orders of magnitude. My favorite theoretical model to explain these results is IDM (Italian Dark Matter), which consists of dark matter that only exists in Italy. Presumably similar particles are responsible for whatever makes Guinness taste better in Ireland.

Comment Is it really diamond? (Score 2) 204

The phase diagram of carbon at extreme temperature and pressure is pretty much unknown. We don't even have any really good studies of liquid carbon. So it's entirely possible the core of such a white dwarf would be made of some other phase of carbon. See, for example, this figure of the carbon phase diagram from density functional theory, showing that over a terapascal, diamond is unstable. Stuff is not the same at the core of a star (even a small one) as in your backyard.

Comment Order of importance (Score 3, Informative) 210

It's not that you're wrong, you're just using different metrics. In physics (and astronomy, I think), the authors are usually listed in decreasing order of work done, starting with the person who did the most. The people at the end of the list have done so little work, why are they even on the paper? Because, as you say, they are listed in increasing order of importance (read: amount of grant money received). If you have enough people, sometimes they just throw them all into alphabetical order and pretend that everybody reading the CVs of the people who actually did the work will somehow know that they did.

This guide may also be helpful: PHD's Guide to the Author List

Comment Re:Ok, interestingish (Score 5, Informative) 210

Here's the paper: An estimate of the electron density in filaments of galaxies at z~0.1.

The student got listed as first author, which is cool for her. The paper itself is a follow-up to Pimbblet's (the actual prof with the actual grant) 2004 study of filaments. The major finding seems to be that the press is gullible enough to print anything if you say an undergrad did the work. In this case, the press manages to avoid looking like total idiots, since the study is pretty cool and interesting. Nonetheless, the hype is vastly out of proportion to the significance.

Space

Newly-Discovered Arm of Milky Way Gives Warped Structure 81

eldavojohn writes "Researchers are now suggesting that a newly-discovered arm of the Milky Way Galaxy gives it a warped structure. Accumulated evidence leads them to claim that an 18-kpc-long arm exists on the other side of the galaxy and this arm traverses some 50 degrees across our sky as an extension of the Scutum-Centaurus Arm (which is one of the two major arms of our galaxy, the other being the Perseus Arm that we can see much more clearly). The researchers conclude that this extension of the Scutum-Centaurus Arm is partially obscured behind the middle of our galaxy because our galaxy is warped 'like the cap from a freshly-opened beer bottle.'"
Technology

Do Gadgets Degrade Our Common Sense? 311

ShelleyPortet writes "In a world where gadgets are growing more sophisticated, human behavior is changing — and not in a good way. That is what Robert Vamosi, author of When Gadgets Betray Us argues in his book, which examines the dangers of our growing dependence on technology. As gadgets develop the ability to multitask seemingly endless functions, Vamosi argues that people are increasingly unable to think for themselves. 'Instead of lifting our heads, looking around and thinking for ourselves,' Vamosi writes, some of us no longer see the world as human beings have for thousands of years and simply accept whatever our gadgets show us."

Comment Everybody is missing the point (Score 5, Interesting) 115

Well, I read all the comments so far and nobody has discussed the actual new parts of the model. The novelty is that the destroyed moon is assumed to be differentiated (The heavy metal and rock fall to the core and the light ices stay on the surface.) and Saturn was in its very early stages, when it was hot and its atmosphere greatly distended. This means that as the moon spirals in toward Saturn, its icy mantle gets stripped off by tidal forces first. That makes a vast disk of icy material from which the inner icy moons and the ring system are formed. Since the denser rocky material at the core of the moon is less affected by tidal forces, it impacts the extended atmosphere of Saturn and gets swallowed up before it has a chance to contribute to the disk. This explains the composition of the rings and moons better than previous models.

The point is not that it was a moon. There was no collision. Takeaway point if tl;dr:

The rings were formed by tidal disruption of a moon with an icy mantle and a rocky core.

Supercomputing

Low Energy Supercomputing 159

Faith Singer at TACC writes "The term 'supercomputing' usually evokes images of large, expensive computer systems that calculate unfathomable algorithms and run on enough energy to support a small city. Now, imagine a supercomputer, but run on the electrical equivalent of three standard-size coffee-makers. This year's international supercomputing conference, SC10, will feature the Student Cluster Competition that challenges students to build, maintain, and run the most-cutting edge, commercially available high-performance computing (HPC) architectures on just 26 amps."
Iphone

iPad Bait and Switch — No More Unlimited Data Plan 670

_KiTA_ writes "AT&T announced today that the iPhone will gain tethering, finally, at an extra $20 a month, but only for people on a new 2GB a month plan. They also quietly announced at the same time the real news — that the $30 Unlimited Data plan on the iPad 3G will be axed in lieu of the same data plan. Yes, this would be the same 'revolutionary data plan' that Steve Jobs was so proud of during the iPad unveiling — it lasted just a month after the 3G model was delayed to May 7. People feeling vibes of previous Apple iDevice releases are not alone. Existing accounts will be allowed to grandfather in, although Apple has removed the ability to purchase the iPad from the online store at this time, and AT&T has a history of changing its plans without warning. Finally, there is no word on what happens if you ever let your Unlimited plan lapse for a month at this time."
Medicine

Scientist Infects Self With Computer Virus 393

superapecommando writes "A British scientist claims to have become the first human to be infected by a computer virus, in an experiment he says has important implications for the future of implantable technology. Dr Mark Gasson from the University of Reading infected a computer chip with the virus, then implanted it in his hand and transmitted the virus to a PC to prove that malware can move between human and computer."

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