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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!"

what a ACT's exercise should look like...

Maybe, you should propose this exercise to the team. You'll see there is not much imagination, unless, you consider imagination equals craziness (bullshit things ... and the too common blah blah in the act). I think this concept is an imaginative credible concept. "anything we might ever see" explains it well.

well, the article is not very detailed so it can be only "du vent" ! did they actually try if such an airplane can fly ??? what about the engine ??? i find the solar impulse (see post below) much more eco-friendly !!! I agree with Leopold that it's quite boring and stays in the mainstream of the production. I'm sure we can do much better !!! What about some really useful things like pills against the flight sickness, and some really good food in the plane ? haha not soon to happen with all the cost reduction. The future of air transport will be a plane without seats, stewards and perhaps even without pilot !!!

haha! is this a joke...?

well i guess the news headline is a bit too much trying to be attractive :)

theoretical physicists... :) Read the last sentence of the paper...in this way anyone can publish in nature...just make a good story with little evidence Did dark matter kill the dinosaurs? The Solar System's periodic passage through a 'dark disk' on the galactic plane could trigger comet bombardments that would cause mass extinctions.

Hmm.. right.. then again, this is not an actual journal publication but a news broadcast. But you are right that the name Nature is attached to it so the journal is definitely banking on their acquired status.

probably not practical for launchers nor for s/c but maybe for suborbital planes? nice idea anyway ...

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?!

Why not power an airplane with an ion thruster?

The UK company developing an engine for a new type of spaceplane says it has successfully demonstrated the power unit's enabling technology.

How many shapes can be obtained by folding a paper and applying just one straight cut? You'll be surprised...

"The theorem is that every pattern (plane graph) of straight-line cuts can be made by folding and one complete straight cut. Thus it is possible to make single polygons (possibly nonconvex), multiple disjoint polygons, nested polygons, adjoining polygons, and even floating line segments and points." - So the you can cut any assembly of polygons but not a single curved edge (with a finite number of folds (points don't count)): useless. :-P

remember the discussion I tried to trigger in the team a few weeks ago ...

I love the linked article provided by Johannes! It expresses very elegantly why I still fail to understand even extremely smart and busy people in my view apparently waiting their time in playing computer games - but I recognise that there is something in games that we apparently need / gives us something we cherish .... "In fact, half a million players so far have registered to help destroy the 64 billion tiny blocks that compose that one gigantic cube, all working in tandem toward a singular goal: discovering the secret that Curiosity's creator says awaits one lucky player inside. That's right: After millions of man-hours of work, only one player will ever see the center of the cube. Curiosity is the first release from 22Cans, an independent game studio founded earlier this year by Peter Molyneux, a longtime game designer known for ambitious projects like Populous, Black & White and Fable. Players can carve important messages (or shameless self-promotion) onto the face of the cube as they whittle it to nothing. Image: Wired Molyneux is equally famous for his tendency to overpromise and under-deliver on his games. In 2008, he said that his upcoming game would be "such a significant scientific achievement that it will be on the cover of Wired." That game turned out to be Milo & Kate, a Kinect tech demo that went nowhere and was canceled. Following this, Molyneux left Microsoft to go indie and form 22Cans. Not held back by the past, the Molyneux hype train is going full speed ahead with Curiosity, which the studio grandiosely promises will be merely the first of 22 similar "experiments." Somehow, it is wildly popular. The biggest challenge facing players of Curiosity isn't how to blast through the 2,000 layers of the cube, but rather successfully connecting to 22Cans' servers. So many players are attempting to log in that the server cannot handle it. Some players go for utter efficiency, tapping rapidly to rack up combo multipliers and get more

why are video games so much different than collecting stamps or spotting birds or planes ? One could say they are all just hobbies

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.

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.

spaceship1 on steroids ...

Looks slightly fragile in the middle...

Nice video featuring the technology. Plus it comes with a good soundtrack! Google's project wing uses a lifting wing concept (more fuel efficient than normal airplane layouts and MUCH more efficient than quadrocopters) but it equips the plane with engines strong enough to hover in a nose up position, allowing vertical landing and takeoff. For the delivery of packages the drone does not even need to land - it can lower them on a wire - much like the skycrane concept used to deliver the Curiosity rover on Mars. Not sure if the skycrane is really necessary but it is certainly cool. Anyways, the video is great for its soundtrack alone! ;-P

Fair enough, but even if you consider advanced/robust/efficient AI, why would you use a drone? Do we envision hundreds of drones above our heads in the street instead of UPS vans, or postmen, considering delivers letters might be more easily achievable. I am not so sure if personal delivery will take this route. On the other hand, if the system would work smoothly, I can image that I'm send a mail with the question whether I'm home (or they might know already from my personal GPS tracker) and then notify me that they are launching my DVD and it will come crashing into my door in 5min.

I'm more curios how they're planning to keep people from stealing the drones. I could do with a drone army myself and having cheap amazon or google drones flying about sounds like a decent source.

A team of researchers at Colorado based Escape Dynamics is reporting that initial tests indicate that it might really be possible to launch space-planes into space using microwaves sent from the ground, to allow for a single stage spacecraft. If the idea pans out, the cost savings for sending satellites (or perhaps humans) into orbit could be considerable.

Not very new, but a very slick video nonetheless! Will it work? I am not so sure whether "just engineering" applies in this case. The array of antenna's required is quite significant to compensate for beam losses. Wall plug efficiency is not that high therefore, then again.. solar energy is for free almost in the future so who cares.. let's go for it! :)

Elon Musk is moving forward with space based internet service...

Facebook announced they are ready to test of of their High Altitude Platform element, a drone of the size of a Boeing 737. See the new here http://phys.org/news/2015-07-facebook-ready-giant-drone-internet.html?utm_source=nwletter&utm_medium=email&utm_content=ctgr-item&utm_campaign=daily-nwletter. It seemed interesting for me that they are developing also a reliable optical communication between this element and scattered ground stations.

Nice link, that thing is huge and I would love to see a drone that size fly. Also, Facebook's Aerospace Team? :)

Giving the title, I think the comment is not necessary...

Haha, nice article : One of the best-known versions of non-general relativistic quantum versions of time travel comes from Wheeler, as described by Feynman in his Nobel Prize lecture [16]: 'I received a telephone call one day at the graduate college at Princeton from Professor Wheeler, in which he said, "Feynman, I know why all electrons have the same charge and the same mass." "Why?" "Because, they are all the same electron!" And, then he explained on the telephone, "Suppose that the world lines which we were ordinarily considering before in time and space - instead of only going up in time were a tremendous knot, and then, when we cut through the knot, by the plane corresponding to a fixed time, we would see many, many world lines and that would represent many electrons, except for one thing. If in one section this is an ordinary electron world line, in the section in which it reversed itself and is coming back from the future we have the wrong sign to the proper time - to the proper four velocities - and that's equivalent to changing the sign of the charge, and, therefore, that part of a path would act like a positron."