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Physicists in the US have made the first ultrathin flat lens. Thanks to its flatness, the device eliminates optical aberrations that occur in conventional lenses with spherical surfaces. As a result, the focusing power of the lens also approaches the ultimate physical limit set by the laws of diffraction.

Really nice indeed! The new flat ultrathin lens is different in that it is a nanostructured "metasurface" made of optically thin beam-shaping elements called optical antennas, which are separated by distances shorter than the wavelength of the light they are designed to focus. These antennas are wavelength-scale metallic elements that introduce a slight phase delay in a light ray that scatters off them. The metasurface can be tuned for specific wavelengths of light by simply changing the size, angle and spacing between the nanoantennas. "The antenna is nothing more than a resonator that stores light and then releases it after a short time delay," Capasso says. "This delay changes the direction of the light in the same way that a thick glass lens would." The lens surface is patterned with antennas of different shapes and sizes that are oriented in different directions. This causes the phase delays to be radially distributed around the lens so that light rays are increasingly refracted further away from the centre, something that has the effect of focusing the incident light to a precise point.

Great engineering feat from Capasso's idea - an integrated flat lens electrically controlled enabling dynamic beam steering. Reconfigurabilility is the aim. The lens can be used microscope systems, holographic and projection imaging, LIDAR and laser printing. Besides working now on the mid-IR, visible light is the target.

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

Sante, Andreas, Luzi, Pacome ... we need you: "But recently White calculated what would happen if the shape of the ring encircling the spacecraft was adjusted into more of a rounded donut, as opposed to a flat ring. He found in that case, the warp drive could be powered by a mass about the size of a spacecraft like the Voyager 1 probe NASA launched in 1977.

Furthermore, if the intensity of the space warps can be oscillated over time, the energy required is reduced even more, White found.

"The findings I presented today change it from impractical to plausible and worth further investigation," White told SPACE.com. "The additional energy reduction realized by oscillating the bubble intensity is an interesting conjecture that we will enjoy looking at in the lab.""

To me, this looks a little bit like the claim "infinity minus one is a little bit less than infinity"...

Luzi I miss you ...

"V3Solar has developed a cone-shaped solar energy harvester that is claimed to generate over 20 times more electricity than a flat panel thanks to a combination of concentrating lenses, dynamic spin, conical shape, and advanced electronics."

Hmm.. that seems counter intuitive... how would it ever be that much better than a flat panel? Rotating the PV will only make sure only parts are illuminated. Operating temperature is a better argument, but that comes at the cost of exposure. Came across this little gem of a webpage, maybe we should outsource our impossibility EM drive work next time? :) https://www.metabunk.org/debunked-v3solars-spinning-solar-panel-cone-spin-cell-coolspin.t1166/

"Some segments of the research community would get their preferences under the House spending bill. For example, it matches the president's request for a 1.5% increase for NASA, to $19 billion, including a 12% increase, to $5 billion, for the space science program. Legislators had already worked out a deal with the White House on the future of the manned space program, and they included funding for an additional shuttle flight in 2011. They even added $35 million to the $20 million increase that the president requested for NASA's education programs, boosting them by a whopping 30% to $180 million. "

Some segments of the research community would get their preferences under the House spending bill. For example, it matches the president's request for a 1.5% increase for NASA, to $19 billion, including a 12% increase, to $5 billion, for the space science program. Legislators had already worked out a deal with the White House on the future of the manned space program, and they included funding for an additional shuttle flight in 2011. They even added $35 million to the $20 million increase that the president requested for NASA's education programs, boosting them by a whopping 30% to $180 million.

In the past 12 months Americans have searched for Python on Google more often than for Kim Kardashian, a reality-TV star. The number of queries has trebled since 2010, while those for other major programming languages have been flat or declining.

Likely this is correlated with the increased interest in machine learning in the past decade - all the popular DL libraries are Python-based after all...

A new blob-like robot described in the journal Advanced Robotics uses springs, feet, "protoplasm" and a distributed nervous system to move in a manner inspired by the slime mold Physarum polycepharum. Watch it ooze across a flat surface, The Blob style: Skip to 1:00 if you just want to be creeped out by its life-like quivering.

Captivated by a strange coiling behavior in the grasping tendrils of the cucumber plant, researchers at Harvard University have characterized a new type of spring that is soft when pulled gently and stiff when pulled strongly. Instead of unwinding to a flat ribbon under stress, as an untwisted coil normally would, the cucumber's tendrils actually coil further.

...interesting discovery that can add something to my ongoing Ariadna...

And here you have the paper published today on Science http://www.sciencemag.org/content/337/6098/1087.full

At least we don't come up with this kind of crap!

OMG ... its coming ... the future we all have dreaded where in perfectly flat caribbean beaches underwater mines are growing like flowers

Instead of round silk threads this spider produces flat ribbons 40-80 nm in thickness. Still the material is as strong as Kevlar and much more elastic.

In the world of mathematical tiling, news doesn't come bigger than this. In the world of bathroom tiling - I bet they're interested too. If you can cover a flat surface using only identical copies of the same shape leaving neither gaps nor overlaps, then that shape is said to tile the plane. Also only mathematicians can put the words "Pentagon", "attack", and "plane" in the same sentence...

I especially love this part of the story: "The hunt to find and classify the pentagons that can tile the plane has been a century-long mathematical quest, begun by the German mathematician Karl Reinhardt, who in 1918 discovered five types of pentagon that do tile the plane. (To clarify, he did not find five single pentagons. He discovered five classes of pentagon that can each be described by an equation. For the curious, the equations are here. And for further clarification, we are talking about convex pentagons, which are most people's understanding of a pentagon in that every corner sticks out.) Most people assumed Reinhardt had the complete list until half a century later in 1968 when R. B. Kershner found three more. Richard James brought the number of types of pentagonal tile up to nine in 1975. That same year an unlikely mathematical pioneer entered the fray: Marjorie Rice, a San Diego housewife in her 50s, who had read about James' discovery in Scientific American. An amateur mathematician, Rice developed her own notation and method and over the next few years discovered another four types of pentagon that tile the plane. In 1985 Rolf Stein found a fourteenth. Way to go!"

A flat metalens based on the control of the diffraction pattern of individual nanoantennas can achieve NA~1 bending light at angles as high as 82º