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Comment Re:The Whole Premise is Flawed (Score 2) 487

There is much more to it. Grad students have their tuition paid out of their supervisors' grants. Additionally, there is a 50 to 60% overhead on the grant, including this tuition payment as well as grad student salary and benefits. A university certainly makes more money from hiring a grad student than the student does.

Comment Re:"Superdecoherence" (Score 5, Informative) 101

From TFA:

In addition, the physicists of the University of Innsbruck have found out that the decay rate of the atoms is not linear, as usually expected, but is proportional to the square of the number of the qubits. When several particles are entangled, the sensitivity of the system increases significantly.

This is somewhat troubling, isn't it? If the decay rate is quadratic in the number of qubits, and this turns out to be due to some fundamental physical law as opposed to limitations of the current technology, does that mean we can never have quantum computers with any significant amount of memory?

Not really. The researchers trapped and entangled 14 ions in a single ion trap. Quantum computers based on ion traps will have thousands of traps, with never more than one or two ions per trap. (Machines with hundreds of traps have been tested, ions moved between traps, etc.; see, e.g., [1]) It has been known since at least 1997 [2] that you can't have a scalable system with only a single ion trap (that would be true even were the decay rate quadratic in the number of ions per trap).

[1] Home, J. P. et al. Complete methods set for scalable ion trap quantum information
processing. Science 325, 1227–1230 (2009). arXiv:0907.1865 [quant-ph]
[2] Wineland, D.J. et al. Experimental issues in coherent quantum state manipulation
of trapped atomic ions. J. Res. Natl. Inst. Stand. Technol. 103, 259–328 (1998). arXiv:quant-ph/9710025

By the way, an arXiv link for this article is arXiv:1009.6126 [quant-ph].

Comment Re:Not "Nobel Prize" (Score 2) 61

It really is *not* widely known as the Nobel prize of computing. The Wikipedia citation is to an ACM press release---and ACM is the organization that gives out the award! In general, the Turing award has had a very poor history of recipients. It is better than the Nobel peace prize but worse than the economics prize (and therefore far worse than physics, etc.).

Comment Re:Caution about ArXiv (Score 1) 421

Formal peer review is itself an appeal to authority.

Appeal to authority may be a fallacy in a logical argument. In a fully logical argument, there are no shortcuts. You can't outsource logic, either to reviewers or moderators. But for most of what we do, we need to judge the credibility of sources and can tolerate some mistakes. There is a sliding scale of credibility.

Anyway, this paper is simple enough to read for anybody with high school-level quantum mechanics background.

Comment Re:GP100M (Score 1) 1042

It may be more clear to say gallons per miles, but it is for the social good to say miles per gallon. Measuring in miles per gallon perceptually exaggerates the benefits of getting cars with marginally improved mileage, leading people to buy more efficient cars than they would be a more clear measurement standard. Measuring in gallons per mile shows much more clearly the quickly diminishing returns of buying more efficient cars.

Transportation

Porsche Unveils 911 Hybrid With Flywheel Booster 197

MikeChino writes "Porsche has just unveiled its 911 GT3 R Hybrid, a 480 horsepower track vehicle ready to rock the 24-hour Nurburgring race this May. Porsche's latest supercar will use the same 911 production platform available to consumers today, with a few race-ready features including front-wheel hybrid drive and an innovative flywheel system that stores kinetic energy from braking and then uses it to provide a 160 horsepower burst of speed. The setup is sure to offer an advantage when powering out of turns and passing by other racers."
Earth

Yellowstone Supervolcano Larger Than First Thought 451

drewtheman writes "New studies of the plumbing that feeds the Yellowstone supervolcano in Wyoming's Yellowstone National Park shows the plume and the magma chamber under the volcano are larger than first thought and contradicts claims that only shallow hot rock exists. University of Utah research professor of geophysics Robert Smith led four separate studies that verify a plume of hot and molten rock at least 410 miles deep that rises at an angle from the northwest."

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