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Submission + - Under Revised Quake Estimates, Dozens of Nuclear Reactors Face Problems (nytimes.com)

Submitted by mdsolar
mdsolar writes: Owners of at least two dozen nuclear reactors across the United States, including the operator of Indian Point 2, in Buchanan, N.Y., have told the Nuclear Regulatory Commission that they cannot show that their reactors would withstand the most severe earthquake that revised estimates say they might face, according to industry experts.

As a result, the reactors’ owners will be required to undertake extensive analyses of their structures and components. Those are generally sturdier than assumed in licensing documents, but owners of some plants may be forced to make physical changes, and are likely to spend about $5 million each just for the analysis.

Submission + - MH370: Chinese patrol ship detects pulse signal (theguardian.com) 1

Submitted by mdsolar
mdsolar writes: A Chinese search ship has detected an electronic pulse in an area of the southern Indian Ocean where it is believed the missing Malaysian Airlines plane crashed, state media has announced.

"Chinese patrol ship Haixun 01 searching for flight MH370 discovered a pulse signal with a frequency of 37.5kHz per second in south Indian Ocean waters Saturday," the official news agency, Xinhua, said.

The single-sentence story is the first potentially positive sign in the race against time to find the Malaysian aircraft's black box. But there is as yet no indication of whether the pulse is in fact connected to the plane, and no wreckage has been found in the area despite a massive international hunt.

Submission + - Most expensive aviation search: $53 million to find flight MH370 (smh.com.au)

Submitted by mdsolar
mdsolar writes: The search and investigation into missing Malaysia Airlines flight MH370 is already the most expensive in aviation history, figures released to Fairfax Media suggest.

The snippets of costings provide only a small snapshot but the $US50 million ($54 million) spent on the two-year probe into Air France Flight 447 — the previous record — appears to have been easily surpassed after just four weeks....

The biggest expense in the search has involved ships, satellites, planes and submarines deployed first in the South China Sea and the Malacca Straits, and then in the remote reaches of the southern Indian Ocean.

Submission + - P=NP Problem Linked To The Quantum Nature Of The Universe

Submitted by KentuckyFC
KentuckyFC writes: One of the greatest mysteries in science is why we don't see quantum effects on the macroscopic scale; why Schrodinger's famous cat cannot be both alive and dead at the same time. Now one theorist has worked out why and says the answer is because P is NOT equal to NP. Here's the thinking. The equation that describes the state of any quantum object is called Schrodinger's equation. Physicists have always thought it can be used to describe everything in the universe, even large objects and perhaps the universe itself. But the new idea is that this requires an additional assumption--that an efficient algorithm exists to solve the equation for complex macroscopic systems. But is this true? The new approach involves showing that the problem of solving Schrodinger's equation is NP-hard. So if macroscopic superpositions exist, there must be an algorithm that can solve this NP-hard problem quickly and efficiently. And because all NP-hard problems are mathematically equivalent, this algorithm must also be capable of solving all other NP-hard problems too, such as the travelling salesman problem. In other words, NP-hard problems are equivalent to the class of much easier problems called P. Or P=NP. But here's the thing: computational complexity theorists have good reason to think that P is not equal to NP (although they haven't yet proven it). If they're right, then macroscopic superpositions cannot exist, which explains why we do not (and cannot) observe them in the real world. Voila!

Comment Re:Bogus (Score 1) 179

by mdsolar (#46649263) Attached to: Vermont Nuclear Plant Seeks Decommission But Lacks Funds
RCP2.6 can't be accomplished with nuclear power: http://www.rmi.org/Knowledge-C... The question, which you have misunderstood, was about subsidies. Coal is heavily subsidized in terms health costs of sulfur, mercury and particulate pollution. Natural gas is not. Is there a carbon subsidy? In the sense that we are suffering dangerous climate change now, there is. We are making extra payouts for crop insurance and flood insurance for example. But, when it comes to disposal, there is no need since cutting emissions also cuts the concentration below the dangerous threshold. So, there is no disposal subsidy.

Comment Re:Nuclear gets the biggest subsidy (Score 0) 179

by mdsolar (#46640233) Attached to: Vermont Nuclear Plant Seeks Decommission But Lacks Funds
Actually, we've only just started with dangerous climate change, and simply cutting emissions takes us back down to a safe climate without any disposal effort, so your supposition that there is an existing subsidy is incorrect. For future emissions above the 270 Gt of carbon included in the IPCC's RCP2.6 one might suppose a hidden subsidy, but not until then. We still have a choice not to make too much carbon dioxide waste. That choice is past with nuclear waste, we've already made too much not to have a need to dispose of it. If fact we are backed up and should probably stop producing nuclear waste until we've got the problem solved.

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