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Each year the dutch NSA (AIVD) comes out with a christmas puzzle (never knew) which consists of 20 severe cryptic questions. Unfortunately, all the questions are in Dutch :( I solved 3 at the moment...

"Australia's Royal Air Force has been left red-faced after a job ad asked applicants to solve a complex math problem was revealed to be unsolvable. Bosses posted the puzzle in a bid to attract the country's best minds to its ranks"

Biologists have long wondered how our organs all grow at the same rate. Now theoretical physicists think they've found a clue in the special way sandpiles grow

The new material matches the properties of a puzzling new form of carbon found in high pressure experiments

After this lunch lecture probably not as ground breaking as I thought earlier but still an interesting read... "The new solution involves supertranslations, something that I have yet to get my head properly around. But it seems to rely on the well known fact that an "image" of infalling matter seems to get imprinted onto the "surface" of a black hole."

link to the paper: http://dx.doi.org/10.1038/nsmb.2119 additional info at: http://fold.it/portal/

Nice easy to read article

Cool stuff! This guy is also interesting: http://cogsci.uci.edu/~ddhoff/HoffmanTime.pdf. Saw him in a conference one, blew my mind :O

Quantum processes shouldn't survive in hot, wet biological systems and yet a growing body of evidence suggests they do. Now physicists think they know how

Yes, because our bosses forced us to write strategic reports on "system of systems" :-)

Oh these terrible ignorant slave masters .... Would love to see your "reports on system of systems" :-)

Mantis shrimp seem to have 12 types of photo-receptive sensors - but this does not really improve their ability to discriminate between colors. Speculation is that they serve as a form of pre-processing for visual information: the brain does not need to decode full color information from just a few channels which would would allow for a smaller brain. I guess technologically the two extremes of light detection would be RGB cameras which are like our eyes and offer good spatial resolution, and spectrometers which have a large amount of color channels but at the cost of spatial resolution. It seems the mantis shrimp uses something that is somewhere between RGB cameras and spectrometers. Could there be a use for this in space?

> RGB cameras which are like our eyes ...apart from the fact that the spectral response of the eyes is completely different from "RGB" cameras (http://en.wikipedia.org/wiki/File:Cones_SMJ2_E.svg) ... and that the eyes have 4 types of light-sensitive cells, not three (http://en.wikipedia.org/wiki/File:Cone-response.svg) ... and that, unlike cameras, human eye is precise only in a very narrow centre region (http://en.wikipedia.org/wiki/Fovea) ...hmm, apart from relying on tri-stimulus colour perception it seems human eyes are in fact completely different from "RGB cameras" :-) OK sorry for picking on this - that's just the colour science geek in me :-) Now seriously, on one hand the article abstract sounds very interesting, but on the other the statement "Why use 12 color channels when three or four are sufficient for fine color discrimination?" reveals so much ignorance to the very basics of colour science that I'm completely puzzled - in the end, it's a Science article so it should be reasonably scientifically sound, right? Pity I can't access full text... the interesting thing is that more channels mean more information and therefore should require *more* power to process - which is exactly opposite to their theory (as far as I can tell it from the abstract...). So the key is to understand *what* information about light these mantises are collecting and why - definitely it's not "colour" in the sense of human perceptual experience. But in any case - yes, spectrometry has its uses in space :-)

An amazing video.. while science is still puzzled what actually happened

There's one very simple explanation I can think of...

While most humans are right-handed, our proteins are made up of lefty molecules. In the same way your left and right hands mirror one another, molecules can assemble in two reflected structures. Life prefers the left-handed version, which is puzzling since both mirrored types form equally in the laboratory.

Using dielectric materials as efficient EM radiators and receivers can scale down these antenna's to the chip level, reducing both weight and power consumption. The infamous internet-of-things one step closer. But could we also transmit power this way?? "In dielectric aerials, the medium has high permittivity, meaning that the velocity of the radio wave decreases as it enters the medium," said Dr Dhiraj Sinha, the paper's lead author. "What hasn't been known is how the dielectric medium results in emission of electromagnetic waves. This mystery has puzzled scientists and engineers for more than 60 years." The researchers determined that the reason for this phenomenon is due to symmetry breaking of the electric field associated with the electron acceleration The researchers found that by subjecting the piezoelectric thin films to an asymmetric excitation, the symmetry of the system is similarly broken, resulting in a corresponding symmetry breaking of the electric field, and the generation of electromagnetic radiation.

Wow, this is a bit frigthening. Another proof that we understand very little about our atmosphere !!!

very interesting indeed!

For non-computer scientists who ever wondered what is this thing that computer scientists keep babbling about after a few beers (apart from MtG)... Relatively correctly explained in this article.

some nice questions to be implemented for newcomers joke interviews

You can use idle computers as extra computing power in a big run, or you can use idle personnel as extra computing power by making them play computer games:

A good occasion to get the idea out of the idea pool...?

Theoretized 80 years ago was Breit-Wheeler pair production in which two photons result in an electron-positron pair (via a virtual electron). It is a relatively simple Feynmann diagram, but the problem is/was how to produce in practice a high energy photon-photon collider... The collider experiment that the scientists have proposed involves two key steps. First, the scientists would use an extremely powerful high-intensity laser to speed up electrons to just below the speed of light. They would then fire these electrons into a slab of gold to create a beam of photons a billion times more energetic than visible light. The next stage of the experiment involves a tiny gold can called a hohlraum (German for 'empty room'). Scientists would fire a high-energy laser at the inner surface of this gold can, to create a thermal radiation field, generating light similar to the light emitted by stars. They would then direct the photon beam from the first stage of the experiment through the centre of the can, causing the photons from the two sources to collide and form electrons and positrons. It would then be possible to detect the formation of the electrons and positrons when they exited the can. Now this is a good experiment... :)

True, but isnt it E2=(pc)^2 + (m0c^2)^2 such that for photons E\propto{pc} and for mass E\propto{mc^2}. I agree it will take a lot of energy, but this assumes that that wont be the problem at least. The question therefore is whether the mass flow of the photon rocket (fuel consumed to create photons, eg fission/fusion) is higher/lower than the mass flow for e-p creation. You are probably right that the low e-p cross-section will favour direct use of photons to create low thrust for long periods of time, but with significant power available the ISP might be higher for e-p pair creation.

In essence the equation tells you that for photons with zero rest mass m0 all the energy will be converted to momentum of the particles. If you want to accelerate e-p then you first spend part of the energy on creating them (~511 keV each) and you can only use the remaining energy to accelerate them. In this case the equation gives you a lower particle momentum which leads to lower thrust (even when assuming 100% acceleration efficiency). ISP is a tricky concept in this case because there are different definitions which clash in the relativistic context (due to the concept of mass flow). R. Tinder gets to a I_SP = c (speed of light) for a photon rocket (using the relativistic mass of the photons) which is the maximum possible relativistic I_SP: http://goo.gl/Zz5gyC .

In a work published on Nature (http://www.nature.com/nature/journal/v517/n7536/full/nature14090.html#affil-auth) a new DFT based simulation of convection in Earth's Core iron shows that electron-electron scattering has a similar contribution to electron's thermal vibration. The outcome is that using the old dynamo theory the simulation matches the Earth magnetic field experimental results, solving an 80 years old puzzle.

Yay to science! I'm always intrigued by related experiments that try to measure material properties at the GPa range. Especially, the efforts of reaching 'metallic hydrogen' (http://en.wikipedia.org/wiki/Metallic_hydrogen), requiring pressures above 25GPa at which hydrogen becomes conductive. It is thought that gas giant planets could have such a core, but no-one has been able to produce/verify this theory as off yet.