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Euler's Partition Function Theory Finished 117

universegeek writes "Mathematician Ken Ono, from Emory, has solved a 250-year-old problem: how to exactly and explicitly generate partition numbers. Ono and colleagues were able to finally do this by realizing that the pattern of partition numbers is fractal (PDF). This pattern allowed them to find a finite, algebraic formula, which is like striking oil in mathematics."

A Mind Made From Memristors 320

Csiko writes "Researchers at Boston University's department of cognitive and neural systems are working on an artificial brain implemented with memristors. 'A memristor is a two-terminal device whose resistance changes depending on the amount, direction, and duration of voltage that's applied to it. But here's the really interesting thing about a memristor: Whatever its past state, or resistance, it freezes that state until another voltage is applied to change it. Maintaining that state requires no power.' Also theoretically described, solid state versions of memristors have not been implemented until recently. Now researchers in Boston claim that memristors are the new key technology to implement highly integrated, powerful artificial brains on cheap and widely available hardware within five years."

Greg Bear, Others Cry Foul on Project Gutenberg Copyright Call 721

Nova Express writes "Recently a lot of science fiction stories from the 1950s and 60s (including work from still-living authors like Frederik Pohl and Jack Vance) have been showing up on Project Gutenberg as being in the public domain. However, according to science fiction writer Greg Bear and his wife Astrid Anderson Bear (daughter of Poul Anderson, some of whose works were among those put up), Project Gutenberg has made a mistake: 'After conducting legal research on the LEXIS database of legal cases, decisions, and precedents, we have demonstrated conclusively that PG was making incorrect determinations regarding public domain status in many, many works that originally appeared in magazine form ... In general, Project Gutenberg is doing a tremendous service by making available texts that have truly long since fallen out of copyright, but they are clearly overstepping their original mandate. They are not merely exploiting orphan works, but practicing a wholesale kidnapping of works that are under copyright protection.'"

Comment Re:None. (Score 1) 728

I wish I had mod points. That obviously wasn't a troll.

At risk of damaging my karma: guys, just because you disagree with it doesn't mean it's trolling. There is no -1 Disagree mod. The poster is pretty obviously arguing a genuinely held opinion and coming back to support it, and yet even their reply post later on has been modded Troll.

I also don't think it's that contentious to claim that parts of our economy are dependent on copyright law. I'd take issue with the insane lengths of copyright periods, not with its mere existence. But that's beside the point!


NASA's Stunning Close-Up Photos of Comet Hartley 2 62

Several readers have sent word that NASA's EPOXI spacecraft performed a close approach to comet Hartley 2 yesterday, taking pictures within roughly 700km of the nucleus. Bad Astronomer Phil Plait has a collection of some fantastic photographs, and you can check out a ton of other images on the mission website. The Planetary Society blog put together a neat animation of the flyby. NASA's mission fact sheet (PDF) explains EPOXI's background — it's the supplemental mission of the Deep Impact craft that smashed a small probe into a different comet back in 2005 — and why Hartley 2 was chosen for this flyby (they couldn't find their original target).

Comment Re:Latency... (Score 1) 145

No, unfortunately. You can't use entanglement to transmit information faster than the speed of light. It's true that under some interpretations you might think of entanglement as meaning that some cause & effect is happening faster than the speed of light, but you can prove that you can't use this to transmit information (you can't control the 'cause').

Comment I do understand quantum computing (Score 1) 145

which means I can tell that I wouldn't have understood it from reading that article.

It's not one of those nonsense articles; the author clearly has some idea what she's talking about, but don't feel like you should be able to get some basic understanding of quantum computing from reading this. The information really isn't there. It starts with 'what is quantum physics' and very quickly moves on to 'what are quantum computers used for'. How they actually work is I think glossed over in the sentence "This shared state means that a change applied to one entangled object is instantly reflected by its correlated fellows - hence the massive parallel potential of a quantum computer. ", and if that was enough explanation for you, you're psychic.

David Mermin's lecture notes in an earlier comment though look great! Thanks for the link.

Also if anyone can explain to me what the article means by:

One more thing, there is a minority of scientists who believe that building a quantum computer will turn out to be out-and-out impossible. However, if those scientists are right, the implication of not being able to build such a machine is that quantum mechanics itself, as a description of nature, is wrong. Either way, the stakes could not be higher.

let me know. I'm guessing that this is a simplistic reference to something real, but I have no idea what, and I can't understand how it's consistent with the fact mentioned earlier in the article that 'toy' (i.e. few-bit) quantum computers have been demonstrated to work in the lab.


Submission + - Cloud Portal to the R Language Cracks Open (

Cloudia writes: Each year at SC, a handful of disruptive technologies are selected as showcase items to represent drastic innovations for high-performance computing. On the list this year is a "Google Docs-like portal for scientific computing in the cloud" that delivers the first front-end door to the R language as well as a host of other useful features and tools for statisticians, scientists and the HPC community at large.

Submission + - HTML5 makes maths easy (

angry tapir writes: "The W3C has updated its MathML standard for rendering mathematical notation on Web pages to better portray basic math symbols, as well as render mathematic symbols in more languages. The World Wide Consortium (W3C) is hoping that this new version of MathML will be rolled into the other group of standards being incorporated in browsers with the HTML5 Web page markup specification, such as CSS and SVG."

Submission + - Hard-to-read fonts improve learning (

arkenian writes: Difficult-to-read fonts make for better learning, according to scientists. The finding is about to be published in the international journal Cognition. Researchers at Princeton University employed volunteers to learn made-up information about different types of aliens — and found that those reading harder fonts recalled more when tested 15 minutes later.

The article goes on to note a second test in a real school environment: "Keen to see if their findings actually worked in practice, the Princeton University team then tested their results on 222 students aged between 15 and 18 at a secondary school in Chesterfield, Ohio."... "Students given the harder-to-read materials scored higher in their classroom assessments than those in the control group. This was the case across a range of subjects — from English, to Physics to History."

Comment Re:Sleep (Score 1) 259

I'm not convinced it's unchangeable, even though I'm in a very similar situation to you. My hours are naturally "late" and gravitate back there every time they're allowed, then stay stable. The only reason I'm not convinced is that several different friends with the same thing have told me they did genuinely and apparently permanently switch to early hours, some years back. In each case the thing which made it happen was having a baby! Maybe baby = early hours + oxytocin = brain reprogramming?

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