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Power

Laser Fusion's Brightest Hope 115

First time accepted submitter szotz writes "The National Ignition Facility has one foot in national defense and another in the future of commercial energy generation. That makes understanding the basic justification for the facility, which boasts the world's most powerful laser system, more than a little tricky. This article in IEEE Spectrum looks at NIF's recent missed deadline, what scientists think it will take for the facility to live up to its middle name, and all of the controversy and uncertainty that comes from a project that aspires to jumpstart commercial fusion energy but that also does a lot of classified work. NIF's national defense work is often glossed over in the press. This article pulls in some more detail and, in some cases, some very serious criticism. Physicist Richard Garwin, one of the designers of the hydrogen bomb, doesn't mince words. When it comes to nuclear weapons, he says in the article, '[NIF] has no relevance at all to primaries. It doesn't do a good job of mimicking secondaries...it validates the codes in regions that are not relevant to nuclear weapons.'"

Comment Re:Is Mathematics Discovered Or Invented? (Score 1) 798

This is actually a smart answer.

IMO, the truths of mathematics are objectively true - and exist independently of human thought. You will nowhere find aliens who have proved that 1+1 = 3, though you may well find some who think the whole idea uninteresting or useless, and even some who cannot understand what you mean by "one". And this applies equally to excruciatingly difficult truths of mathematics. Fermat's Last Theorem is objectively true, and all that Wells did was find a way to show everyone that.

Nevertheless, mathematics is an intensely creative process, and the creativity is in what you think about. There are lots of mathematical objects out there, and some of them are more fruitful and more interesting to us humans than others. Oftentimes, the key to a hard proof is coming up with the right objects, the right definitions, to allow you to make the leap of logic to the larger goal. These defined objects have also always been out there in the timeless mathematical universe, but right along with them are an infinite number of useless objects and concepts, as well as some wondrous objects that no one has yet found the use of.

This is one reason that human mathematicians beat theorem-provers. The mechanical theorem provers have no concept of interestingness, and will prove an infinite number of theorems of no possible interest. Real mathematicians have the intuition, and the cleverness, to not waste their time in the chaff, and to seek out the beautiful and productive. It is extraordinarily creative. And the key act is often "Let's give this thing I have just come up with a name, so it is easier to work with". In other words, the act of definition.
Upgrades

The Economics of Chips With Many Cores 343

meanonymous writes "HPCWire reports that a unique marketing model for 'manycore' processors is being proposed by University of Illinois at Urbana-Champaign researchers. The current economic model has customers purchasing systems containing processors that meet the average or worst-case computation needs of their applications. The researchers contend that the increasing number of cores complicates the matching of performance needs and applications and makes the cost of buying idle computing power increasingly prohibitive. They speculate that the customer will typically require fewer cores than are physically on the chip, but may want to use more of them in certain instances. They suggest that chips be developed in a manner that allows users to pay only for the computing power they need rather than the peak computing power that is physically present. By incorporating small pieces of logic into the processor, the vendor can enable and disable individual cores, and they offer five models that allow dynamic adjustment of the chip's available processing power."

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