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Another story about the search for extra dimensions through modifications to gravity on small scales.

Video about Higher dimensions This is my first post - hope it works. This is one of fav vids. Maybe you have seen already, but for those who haven't, you should find it interesting.

[MaRu] Are you curious about the origin of images I put on my desktop wallpaper? This 2-hours (!) movie should help you understand what they are and where do they come from. Even if you're a biologist ;-) You can watch the trailer here: http://youtube.com

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.

Researchers in Japan have developed what may be the first string-theory model with a natural mechanism for explaining why our universe would seem to exist in three spatial dimensions if it actually has six more. According to their model, only three of the nine dimensions started to grow at the beginning of the universe, accounting both for the universe's continuing expansion and for its apparently three-dimensional nature. ... The team has yet to prove that the Standard Model of particle physics will show up in its model,...

Francesco please look at this and get back wrt to the /. question .... thanks

love this one ... it seems to take physicist to explain to the AI crowd what they are actually doing ... Deep learning is a broad set of techniques that uses multiple layers of representation to automatically learn relevant features directly from structured data. Recently, such techniques have yielded record-breaking results on a diverse set of difficult machine learning tasks in computer vision, speech recognition, and natural language processing. Despite the enormous success of deep learning, relatively little is understood theoretically about why these techniques are so successful at feature learning and compression. Here, we show that deep learning is intimately related to one of the most important and successful techniques in theoretical physics, the renormalization group (RG). RG is an iterative coarse-graining scheme that allows for the extraction of relevant features (i.e. operators) as a physical system is examined at different length scales. We construct an exact mapping from the variational renormalization group, first introduced by Kadanoff, and deep learning architectures based on Restricted Boltzmann Machines (RBMs). We illustrate these ideas using the nearest-neighbor Ising Model in one and two-dimensions. Our results suggests that deep learning algorithms may be employing a generalized RG-like scheme to learn relevant features from data.

A new so called 5D data storage that could potentially survive for billions of years. The research consists of nanostructured glass that can record digital data in five dimensions using femtosecond laser writing.

Yes Alex, indeed, the durability is the point I think they highlight and focus on (besides the fact the abstract says something as the extrapolated decay time being comparable to the age of the Universe..). Indeed memories face problems with retention time. Most of the disks retain the information up to 10 years. When enterprises want to store data for longer times than this they use... yeah, magnetic tapes :-). Check a interesting article about magnetic tape market revival here http://www.information-age.com/technology/data-centre-and-it-infrastructure/123458854/rise-fall-and-re-rise-magnetic-tape I compared for fun, to have one idea of what we were talking about. I am also very curious so see the writing and reading times in this new memory :)

But how can glass store the information so long? Glass is not even solid?!

Related paper at: http://journals.aps.org/prl/pdf/10.1103/PhysRevLett.118.080501

isabelle: an option for space baed laser?

The fact that the graphene can emit laser pulses at different wavelengths might be interesting for spectroscopy and laser communications. The tiny dimensions might also help in miniaturization of devices (although apparently a conventional laser is necessary for pumping...). Maybe it would be possible to make very efficient displays with such a technology..?

I hate scorpions, but this could be a nice subject for a future Ariadna study! This north African desert scorpion, doesn't dig burrows to protect itself from the sand-laden wind (as the other scorpions do). When the sand whips by at speeds that would strip paint away from steel, the scorpion is able to scurry off without apparent damage.

Nice research, though they have done almost all the work that we could do in an Ariadna, didnt they? "To check, they took further photographs. In particular, they used a laser scanning system to make a three-dimensional map of the armour and then plugged the result into a computer program that blasted the virtual armour with virtual sand grains at various angles of attack. This process revealed that the granules were disturbing the air flow near the skeleton's surface in ways that appeared to be reducing the erosion rate. Their model suggested that if scorpion exoskeletons were smooth, they would experience almost twice the erosion rate that they actually do. Having tried things out in a computer, the team then tried them for real. They placed samples of steel in a wind tunnel and fired grains of sand at them using compressed air. One piece of steel was smooth, but the others had grooves of different heights, widths and separations, inspired by scorpion exoskeleton, etched onto their surfaces. Each sample was exposed to the lab-generated sandstorm for five minutes and then weighed to find out how badly it had been eroded. The upshot was that the pattern most resembling scorpion armour-with grooves that were 2mm apart, 5mm wide and 4mm high-proved best able to withstand the assault. Though not as good as the computer model suggested real scorpion geometry is, such grooving nevertheless cut erosion by a fifth, compared with a smooth steel surface. The lesson for aircraft makers, Dr Han suggests, is that a little surface irregularity might help to prolong the active lives of planes and helicopters, as well as those of scorpions."

What bugs me (pardon the pun) is that the dimensions of the pattern they used were scaled up by many orders of magnitude, while "grains of sand" with which the surface was bombarded apparently were not... Not being a specialist in the field, I would nevertheless expect that the size of the surface pattern *in relation to* to size of particles used for bombarding would be crucial.

beautiful and hypnotic, but I'd like to know exactly what it is they are visualizing. These don't seem to be the changes in people's locations during phone calls...

If you've ever flown an R/C plane, you know how nerve wracking it can be. Navigating in three dimensions opens up the possibility to run into so many things, and a single crash could be your last. Now, a team from EPFL's Laboratory of Intelligent Systems has been working on a UAV called the AirBurr.

An approach to robot design that makes sense. I can see applications to planetary explorers here.

A simple cube open at the top can increase the annual energy density generation by a factor (depending on the latitude) of 2 - 3.8 compared to a flat horizontal panel, versus an increase by a factor of 1.3 - 1.8 achieved from a flat panel using dual-axis tracking. Genetic algorithm are used to optimize the energy production in a day for arbitrarily shaped 3D solar cells confined to a given area footprint and total volume doi:10.1063/1.3308490 could be interesting to investigate

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.

A 60-year-old theory about the structure of the magnetic fields that surround Earth has been confirmed directly for the first time. The lead author of the paper is an undergraduate student who invented a way to view the Earth's magnetosphere in three dimensions.

very nice!! could not find the dimensions yet ...

20m diagonal http://www.jspec.jaxa.jp/e/activity/ikaros.html http://www.jspec.jaxa.jp/e/activity/images/ikaros/pic_07_l.jpg

that is honestly a little bit less impressive than I had hoped for ... this "just" 200 m2 ... our Furoshiki net had already 130m2 and we deployed it within 1 min under much worse conditions ...

Some interesting ideas for our crowdsourcing game in here.