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Interesting research field about self-propelled particle swarms: very simple rules lead to complex behavior - in a real-world experiment!

A team of researchers in TU berlin and Caltech used Schrödinger's equation to visualise superfluidic flow (fluids with zero viscosity). Smoke and dry ice are close to this state in nature. Strangely enough for an equation that describes subatomic particles, it works, and reproduces experimental results better that Euler and Langrange schemes.

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.

Julius von Bismarck is only 28 years old, but his artistic resume is already several pages long. He's currently taking time off from school to be the new artist in residence at CERN ? the world's biggest particle physics research facility, home of the Large Hadron Collider.

Perhaps a new role for the ACT!?

very good idea - one that already Andrés had way back and a few years ago I was in contact with a group in Amsterdam who was interested but it never materialised ... any good recommendations? this Bismark guy seems to be a nice chap to have around in the office according to the photo on the site: long beard, a bottle of wine in the office and steering out of the window in search for ideas ... give the ugly office he might even want to swap it with our nice semi open space! :-)

Latest simulation shows that the magnetic nozzles required for antimatter propulsion could be vastly more efficient than previously thought--and built with today's technologies

Tomorrow, at 9am EST, scientists at the Large Hadron Collider (LHC) at CERN in Switzerland are expected to announce, with fairly strong certainty, that they have observed the Higgs boson "God" particle at a mass-energy of 125 GeV. For just over a week, rumors have been rife that observations with 2.5 to 3.5 sigma certainty (96% to 99.9%) have been made.

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,...

The first solid experimental evidence for the existence of the Higgs boson has been unveiled today by physicists working on the Large Hadron Collider (LHC) at CERN in Geneva. Members of the ATLAS experiment revealed evidence that the Higgs particle has a mass of about 126 GeV/c2. "By 2014/2015 we could have enough additional data to eliminate large classes of theories that attempt to explain the Higgs,"

magic :-)

"self-bunching effect" haha

Sante: did you see this?

Maybe a stupid question: The authors argue with the results obtained by Cohen and Glashow [2]. In [2] ist was stated that superluminal neutrinos should lose energy by producing photons and e+e- pairs. This should be observable. These conslusions are based on known physics (I guess), i.e. on the laws valid for subluminal conditions. How reasonable is it to apply (i.e. to assume the validity of) the same laws for superluminal particles?

Earth has had a ring of particles (similar to Saturn's) for a short period of time. And it is manmade.

Looks fantastic!

Sounds like a great tool for calculation and may provide some deeper understanding. But: I think their comments about space and time are misleading. Often you can ignore space and time when you just want the probability of an event (and it makes your calculations easier) but especially in the low-energy regime an event is clearly localized.

where is Luzi? where is Anna? where is Sante? when you need them?

Plastic needs a timescale of millenia to dissolve in the ocean and in the meantime it is accumulated in the water due to systematic dumping of garbage in the ocean since decades. Deploying buoyant devices at the location of the gyres (permanent circular currents in the ocean) is proposed for collecting the thin particles. The ambitious concept was developped by a Delft student, presented at a TEDx (see link), made a feasibility study through crowdfunding and now announces a public contest for developing mechanical parts of the harvesting system.

To follow up our discussio at breakfast

For all your statistics needs. The "Plastic Debris in the World's Oceans Report - UNEP" www.unep.org/regionalseas/marinelitter/.../docs/plastic_ocean_report.pdf‎ "Densities of plastic debris (Moore et al. 2001). Using nets to collect debris, the abundance of floating plastic averaged 334,271 pieces/km2" More worrying maybe is (http://www.ncbi.nlm.nih.gov/pubmed/22610295) "Our oceans eventually serve as a sink for these small plastic particles ("UV degraded surface plastic") and in one estimate, it is thought that 200,000 microplastics per km(2) of the ocean's surface commonly exist."

Researchers in Bangalore, India together with the Indian Space Research organization come up with an intelligent self-healing algorithm that can locate open-circuits faults and repair them in real-time. They used an insulating silicon oil containing conductive particles. Whenever a fault happens, an electric field develops there, causing the fluid to move in a 'thermodynamic automaton' way repairing the fault. The researchers make clear it could be one advantage for electronics in harsh environments, such as in space satellites.

Waves of electrons have been bent backward in a sheet of graphene, allowing physicists to focus electrons the way a lens focuses light. Electrons coursing through a sheet of carbon atoms exhibited negative refraction, bending at angles not seen in nature. By exploiting this unusual bending, the researchers created a lenslike device to focus the electrons to a tiny point. The new technique could help physicists learn how to manipulate electrons in the tight confines of miniaturized electronic devices, where the particles often behave like waves.

and the race begins !

"more than 2000 authors from 166 institutions in 38 countries"... I want to see their papers :-)

antihydrogen propulsion...?

didn't roger write an assessment of antimatter propulsion when he was in the ACT?

yeah the problem is the amount of antimatter you can get and more specifically how to trap it. I found that you would need around one gram to go to the outer Solar System. So we are far from that, but finding an efficient way to trap it, with an electromagnetic trap rather than solid walls is a first step !

nice!