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Cheap and scalable invisibility cloaks being developed. The setup is so trivial that I would almost call it a "trick" (as in "Magicians trick"): 6 prisms of n=1.78 glass. Nontheless, it does the job of cloaking an object at visible wavelengths and from several directions.

Is this really new? I don't know, but I know that the original idea of cloaking was pretty different. When cloaking as an application of transformation optics became popular people tried to make devices that work for any incidence angle, any polarization and in full wave optics (not just ray approximation). This is really hard to achieve and I guess that the people that tried to make such devices knew exactly that the task becomes almost trivial by dropping at least two of the three conditions above.

I think it is very easy to call something trivial when you're not the one who invested considerable time (5 min in my case) to design a cloaking device and fill the coffee mugs with water... Also, I did not really violate that many conditions: true I reduced the number of dimensions in which the device works to 1 (as opposed to the 2 dimensions of many metamaterial cloaks). However the polarization should not be affected in my setup as well as the wave phase and wave vector (so it works in full wave optics) - apart maybe from the imperfect lens distortion, but hey I was improvising.

In work that has major implications for improving the performance of building insulation, scientists at the University of Namur in Belgium and the University of Hassan I in Morocco have calculated that hairs that reflect infrared light may contribute significant insulating power to the exceptionally warm winter coats of polar bears and other animals.

That's quite interesting. Maybe the future of buildings and spacecraft is furry?

".... taking at least 50kg of payload into a polar orbit with a minimum altitude of 400km (248 miles), but engineers would aim to get significant additional performance. "We'd be looking at a range from 50 to up to a maximum of 200kg because you'd want to do different sizes of satellite," said Mr Whitehorn."

and all this without magic metamaterials ...

It's funny to see how people get more and more humble in the desperate attempt to save their stupid ideas... At the beginning was the brave and bold aim to cloak something in free space (in a sphere or a cylinder). This requires inhomogeneous, anisotropic, magnetic materials; hopeless!! So one reduces to one polarization, now we have inhomogenous, anisotropic materials; still hopeless! At this point one downgraded the pretension: instead of cloaking in free space, we make a "carpet cloak" and hide an object behind an invisible dent in a mirror. But if that shall be continuous, we still need inhomogeneity and this is very hard. So now instead of a dent we take a cone and then it is claimed to work ... for ONE polarization. But of course the cloak can't work at all incident angles... irony of fate: everything is now made from birefringent media, the antithesis of what the metamaterials dogma was at the beginning!

Hi Luzi, can you please send me the paper. We are writing a project based on sulfates and carbonates, and all this BS sounds great for the introduction (The authors used Calcite as birefringent material)

Graphene miracles

Actually since this graphene hype started, being more or less a physics laic, I keep wondering how much of these promised miracles will in fact be delivered? Any chance for an expert's opinion?

Multiplexed optical recording provides an unparalleled approach to increasing the information density beyond 1012 bits per cm3 (1 Tbit cm-3) by storing multiple, individually addressable patterns within the same recording volume. Although wavelength, polarization and spatial dimension have all been exploited for multiplexing, these approaches have never been integrated into a single technique that could ultimately increase the information capacity by orders of magnitude.

Another underestimated source of CO2, are turbulent waters. "The stronger the turbulences at the water's surface, the more CO2 is released into the atmosphere. The combination of maps and data revealed that, while the CO2 emissions from lakes and reservoirs are lower than assumed, those from rivers and streams are three times as high as previously believed." Alltogether the emitted CO2 equates to roughly one-fifth of the emissions caused by humans. Yet more stuff to model...

Nasia, I thought about your statement carefully - and I cannot agree with you. Water is not a greenhouse gas. It is instead a liquid. Also, I can't believe you keep feeding the troll! :-P But on a more topical note: I think it is an over-simplification to call water a greenhouse gas - water is one of the most important mechanisms in the way Earth handles heat input from the sun. The latent heat that you mention actually cools Earth: solar energy that would otherwise heat Earth's surface is ABSORBED as latent heat by water which consequently evaporates - the same water condenses into rain drops at high altitudes and releases this stored heat. In effect the water cycle is a mechanism of heat transport from low altitude to high altitude where the chance of infrared radiation escaping into space is much higher due to the much thinner layer of atmosphere above (including the smaller abundance of greenhouse gasses). Also, as I know you are well aware, the cloud cover that results from water condensation in the troposphere dramatically increases albedo which has a cooling effect on climate. Furthermore the heat capacity of wet air ("humid heat") is much larger than that of dry air - so any advective heat transfer due to air currents is more efficient in wet air - transporting heat from warm areas to a natural heat sink e.g. polar regions. Of course there are also climate heating effects of water like the absorption of IR radiation. But I stand by my statement (as defended in the above) that rain cools the atmosphere. Oh and also some nice reading material on the complexities related to climate feedback due to sea surface temperature: http://journals.ametsoc.org/doi/abs/10.1175/1520-0442(1993)006%3C2049%3ALSEOTR%3E2.0.CO%3B2

I enjoy trolling conversations when there is a gain for both sides at the end :-) . I had to check upon some of the facts in order to explain my self properly. The IPCC report states the greenhouse gases here, and water vapour is included: http://www.ipcc.ch/publications_and_data/ar4/wg1/en/faq-2-1.html Honestly, I read only the abstract of the article you posted, which is a very interesting hypothesis on the mechanism of regulating sea surface temperature, but it is very localized to the tropics (vivid convection, storms) a region of which I have very little expertise, and is difficult to study because it has non-hydrostatic dynamics. The only thing I can comment there is that the authors define constant relative humidity for the bottom layer, supplied by the oceanic surface, which limits the implementation of the concept on other earth regions. Also, we may confuse during the conversation the greenhouse gas with the Radiative Forcing of each greenhouse gas: I see your point of the latent heat trapped in the water vapour, and I agree, but the effect of the water is that it traps even as latent heat an amount of LR that would otherwise escape back to space. That is the greenhouse gas identity and an image to see the absorption bands in the atmosphere and how important the water is, without vain authority-based arguments that miss the explanation in the end: http://www.google.nl/imgres?imgurl=http://www.solarchords.com/uploaded/82/87-33833-450015_44absorbspec.gif&imgrefurl=http://www.solarchords.com/agw-science/4/greenhouse--1-radiation/33784/&h=468&w=458&sz=28&tbnid=x2NtfKh5OPM7lM:&tbnh=98&tbnw=96&zoom=1&usg=__KldteWbV19nVPbbsC4jsOgzCK6E=&docid=cMRZ9f22jbtYPM&sa=X&ei=SwynUq2TMqiS0QXVq4C4Aw&ved=0CDkQ9QEwAw

The device, like dolphins, sends out two pulses in quick succession to allow for a targeted search for semiconductor devices, cancelling any background "noise",

Could it be used to measure ocean acidification? I found a study that links sound wave propagation with ocean acidity. Maybe we are able to do such measurement from space even? "Their paper, "Unanticipated consequences of ocean acidification: A noisier ocean at lower pH," published last week in the journal Geophysical Research Letters, found that fossil fuels are turning up the ocean's volume. Since the beginning of the Industrial Revolution, the overall pH of the world's oceans has dropped by about 0.1 units, with more of the changes concentrated closer to the poles. The authors found that sound absorption has decreased by 15 percent in parts of the North Atlantic and by 10 percent throughout the Atlantic and Pacific"

The last time I asked an oceanographer for the use of acoustic waves, she said it is still a bit problematic method to take into account its data, but we were referring to measuring ocean circulation. It may be more conclusive for PH measurements, though. The truth is that there is a whole underwater network with pulse emmitters/receivers covering the North Atlantic basin, remnant infrastructure for spying activities in the WW2 and in the cold war, that stays unexploited. We should look more into this idea

Trends in materials and condensed matter. Check out the topological insulators. amazing field.

I will try my best. In a nutshell: http://www.nature.com/news/2010/100714/full/466310a.html

*you* tried *your* best .... ??

"We fit data to zonal interaction models and characterize which individual interaction forces suffice to explain observed spatial patterns." You can get the paper from the first author's website: http://people.stfx.ca/rlukeman/research.htm

PNAS? Didnt strike me as sth very new though... We should refer to it in the roots study though: "Social organisms form striking aggregation patterns, displaying cohesion, polarization, and collective intelligence. Determining how they do so in nature is challenging; a plethora of simulation studies displaying life-like swarm behavior lack rigorous comparison with actual data because collecting field data of sufficient quality has been a bottleneck." For roots it is NO bottleneck :) Tobias was right :)

Here they assume all relevant variables influencing behaviour are being observed. Namely, the relative positions and orientations of all ducks in the swarm. So, they make movies of the swarm's movements, process them, and them fit the models to that data. In the roots, though we can observe the complete final structure, or even obtain time-lapse movies showing how that structure came out to be, getting the measurements of all relevant soil variables (nitrogen, phosphorus, ...) throughout the soil, and over time, would be extremely difficult. So I guess a replication of the kind of work they did, but for the roots, would be hard. Nice reference though.

Jeremy England, a 31-year-old assistant professor at the Massachusetts Institute of Technology, has derived a mathematical formula that he believes explains this capacity. The formula, based on established physics, indicates that when a group of atoms is driven by an external source of energy (like the sun or chemical fuel) and surrounded by a heat bath (like the ocean or atmosphere), it will often gradually restructure itself in order to dissipate increasingly more energy. This could mean that under certain conditions, matter inexorably acquires the key physical attribute associated with life. The simulation results made me think of Jojo's attempts to make a self-assembling space structure. Seems he may have been on the right track, just not thinking big enough

:-P Thanks Thijs... I do not agree with the premise of the article that a possible correlation of energy dissipation in living systems and their fitness means that one is the cause for the other - it may just be that both go hand-in-hand because of the nature of the world that we live in. Maybe there is such a drive for pre-biotic systems (like crystals and amino acids), but once life as we know it exists (i.e., heredity + mutation) it is hard to see the need for an amendment of Darwin's principles. The following just misses the essence of Darwin: "If England's approach stands up to more testing, it could further liberate biologists from seeking a Darwinian explanation for every adaptation and allow them to think more generally in terms of dissipation-driven organization. They might find, for example, that "the reason that an organism shows characteristic X rather than Y may not be because X is more fit than Y, but because physical constraints make it easier for X to evolve than for Y to evolve." Darwin's principle in its simplest expression just says that if a genome is more effective at reproducing it is more likely to dominate the next generation. The beauty of it is that there is NO need for a steering mechanism (like maximize energy dissipation) any random set of mutations will still lead to an increase of reproductive effectiveness. BTW: what does "better at dissipating energy" even mean? If I run around all the time I will have more babies? Most species that prove to be very successful end up being very good at conserving energy: trees, turtles, worms. Even complexity of an organism is not a recipe for evolutionary success: jellyfish have been successful for hundreds of millions of years while polar bears are seem to be on the way out.