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Comment Cough, cough... (Score 4, Interesting) 347

To put it simply, this is BS, on all levels. The summary is just wrong, teleportation doesn't even appear in the article on arXiv. But then the arXiv article is ridiculous. It's a thinly veiled attempt to play with homeopathy: "high dilutions", "mechanical agitation between each dilution", and low frequency EM taking the place of "concussing", "water nanostructures" formed on the DNA which can be used to recreate the DNA sequence? And the paper is totally amateur hour. In summary: It's BS.

Comment Nice article (Score 5, Informative) 107

Pretty good article (the original in J. Neurosci). Alzheimer's has long been believed to be caused by aggregates of amyloid-beta protein, but exactly how they kill neurons (and in what stage of aggregation) has been pretty controversial. They showed a pathway from the amyloid-beta through this N-SMase to neuron death in small assemblies _and_ in larger aggregates, which should make everybody happy (or maybe no one). The important caveat though is that this was in vitro testing, and everything to do with studying Alzheimer's has been confounded by the subtle differences between in vivo and in vitro.

Comment Re:Factor 30 (Score 1) 113

From the abstract at Science: "Cloaking operation with large bandwidth of unpolarized light from 1.4- to 2.7-m wavelength is demonstrated" -- that's only a factor of 2 to 4 longer than visible red light. The factor of 30 is the reduction required in the size of the crystal features in the metamaterial. But I agree that we're still a long way from being able to NOT see a Klingon Bird of Prey...

Comment Not the right article (Score 1) 418

Doesn't anyone read the articles? It says that the article in Phys. Rev. Lett. was published _today_, October 13, 2009. The article that was linked to is two years old and not really relevant. This is the one they're talking about: http://link.aps.org/doi/10.1103/PhysRevLett.103.160502 There's a preprint at: http://arxiv.org/abs/0905.3417 The gist of it is that one can consider a fundamental step of a computation to be the evolution of a quantum system from a state to an orthogonal state (cause if they aren't orthogonal, you're going to get the answer wrong). They figure out the maximum rate at which the system can evolve between orthogonal states, which sets a maximum to the speed of the computation. Turns out that the rate is proportional to the difference in energy of the two states -- which means that you can drive the computation faster by choosing two states that have very different energies. But if you do that, since you need to have a power source driving the system between the two energy levels, you have to spend a lot of energy to keep the rate up. Sort of obvious, but they work out the details with explicit lower bounds for the first time

Comment Flatland (Edwin Abbott) (Score 1) 434

_Flatland_ is a spectacular story that many mathematicans and scientists mention as having been an inspiration when they were young.

At my high school in California a couple of years ago we developed a unit based on _Flatland_ that involved all four core academic subjects -- in the english class they actually read the book and discussed literary and stylistic aspects. In the history class they discussed the allegory being made about social class and gender. In the math class they talked about the geometry, and in my science class we talked about the role of geometry in understanding physics and chemistry, and did exercises and problems that drove home that point. It helped that this high school had a strong core teacher team that collaborated daily on coordinating lessons and sharing notes on struggles our students were having -- so we were already focused on interdisciplinary work and helping the students make connections between different subjects.

I applaud what you are trying to do, and reccomend that whatever materials you choose, you try to coordinate some of them with the other teachers at your level -- it works!

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