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If I could write, this is exactly what I would write about rocket, GO, and so on... :) "we are decadent and tired. But none of the bright young up-and-coming economies seem to be interested in anything besides aping what the United States and the USSR did years ago. We may, in other words, need to look beyond strictly U.S.-centric explanations for such failures of imagination and initiative. ... Those are places we need to go if we are not to end up as the Ottoman Empire of the 21st century, and yet in spite of all of the lip service that is paid to innovation in such areas, it frequently seems as though we are trapped in a collective stasis." "But those who do concern themselves with the formal regulation of "technology" might wish to worry less about possible negative effects of innovation and more about the damage being done to our environment and our prosperity by the mid-20th-century technologies that no sane and responsible person would propose today, but in which we remain trapped by mysterious and ineffable forces."

Would have been nice if it were historically more accurate and less polemic / superficial

mmmh... the wheel is also an old invention... there is an idea behind but this article is not very deepfull, and I really don't think the problem is with innovation and lack of creative young people !!! look at what is done in the financial sector...

Who are the most ruthless capitalists in the western world? Whose monopolistic practices make Walmart look like a corner shop and Rupert Murdoch a socialist? You won't guess the answer in a month of Sundays. While there are plenty of candidates, my vote goes not to the banks, the oil companies or the health insurers, but - wait for it - to academic publishers.

fully agree ... "But an analysis by Deutsche Bank reaches different conclusions. "We believe the publisher adds relatively little value to the publishing process … if the process really were as complex, costly and value-added as the publishers protest that it is, 40% margins wouldn't be available." Far from assisting the dissemination of research, the big publishers impede it, as their long turnaround times can delay the release of findings by a year or more." very nice also: "Government bodies, with a few exceptions, have failed to confront them. The National Institutes of Health in the US oblige anyone taking their grants to put their papers in an open-access archive. But Research Councils UK, whose statement on public access is a masterpiece of meaningless waffle, relies on "the assumption that publishers will maintain the spirit of their current policies". You bet they will. In the short term, governments should refer the academic publishers to their competition watchdogs, and insist that all papers arising from publicly funded research are placed in a free public database. In the longer term, they should work with researchers to cut out the middleman altogether, creating - along the lines proposed by Björn Brembs of Berlin's Freie Universität - a single global archive of academic literature and data. Peer-review would be overseen by an independent body. It could be funded by the library budgets which are currently being diverted into the hands of privateers. The knowledge monopoly is as unwarranted and anachronistic as the corn laws. Let's throw off these parasitic overlords and liberate the research that belongs to us."

It is a really great article and the first time I read something in this direction. FULLY AGREE as well. Problem is I have not much encouraging to report from the Brussels region...

Just read about this, it looks like an interesting example of bottom-up innovation and self-organization.

That's really amazing. The problem is: driving drunk, too fast or without stopping at red traffic lights are the first causes of traffic fatalities, and finding a solution is really important... But those guys want to read our minds to see if there are

What are the defining discoveries, moments of inspiration, or shifts in understanding that have shaped the dynamic field of materials science we know today. Here's what we think are the most significant.

Regardless how good the intention of the government might have been, the facts are that tested implementations of the ePassports Inspection System are not secure.

[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

Next astronaut suit: Electronic systems that offer elastic mechanical responses to high-strain deformations are of growing interest because of their ability to enable new biomedical devices and other applications whose requirements are impossible to satis

Theo Jansen is an artist and kinetic sculptor living and working in Holland. He builds large works which resemble skeletons of animals which are able to walk using the wind on the beaches of the Netherlands. His animated works are a fusion of art and engi

A recently-published book by the Ubuntu Community Manager, Jono Bacon. I just started reading it: lots of information, experiences and revealing hints on how open-source communities are born and evolve today.

"Since I released The Art of Community, one thing has become evident: the people who are buying it are awesome. If you have bought it you are awesome. If you have not, you too can be awesome." To me seems more interesting the topic than the author. I have the impression that many people in this community behave like high-school pupils, though their production it's absolutely "awesome".

Awesome!

Theoretized 80 years ago was Breit-Wheeler pair production in which two photons result in an electron-positron pair (via a virtual electron). It is a relatively simple Feynmann diagram, but the problem is/was how to produce in practice a high energy photon-photon collider... The collider experiment that the scientists have proposed involves two key steps. First, the scientists would use an extremely powerful high-intensity laser to speed up electrons to just below the speed of light. They would then fire these electrons into a slab of gold to create a beam of photons a billion times more energetic than visible light. The next stage of the experiment involves a tiny gold can called a hohlraum (German for 'empty room'). Scientists would fire a high-energy laser at the inner surface of this gold can, to create a thermal radiation field, generating light similar to the light emitted by stars. They would then direct the photon beam from the first stage of the experiment through the centre of the can, causing the photons from the two sources to collide and form electrons and positrons. It would then be possible to detect the formation of the electrons and positrons when they exited the can. Now this is a good experiment... :)

True, but isnt it E2=(pc)^2 + (m0c^2)^2 such that for photons E\propto{pc} and for mass E\propto{mc^2}. I agree it will take a lot of energy, but this assumes that that wont be the problem at least. The question therefore is whether the mass flow of the photon rocket (fuel consumed to create photons, eg fission/fusion) is higher/lower than the mass flow for e-p creation. You are probably right that the low e-p cross-section will favour direct use of photons to create low thrust for long periods of time, but with significant power available the ISP might be higher for e-p pair creation.

In essence the equation tells you that for photons with zero rest mass m0 all the energy will be converted to momentum of the particles. If you want to accelerate e-p then you first spend part of the energy on creating them (~511 keV each) and you can only use the remaining energy to accelerate them. In this case the equation gives you a lower particle momentum which leads to lower thrust (even when assuming 100% acceleration efficiency). ISP is a tricky concept in this case because there are different definitions which clash in the relativistic context (due to the concept of mass flow). R. Tinder gets to a I_SP = c (speed of light) for a photon rocket (using the relativistic mass of the photons) which is the maximum possible relativistic I_SP: http://goo.gl/Zz5gyC .

From the article: By the end of September 2014, Jason Budinoff, an aerospace engineer at NASA's Goddard Space Flight Center (Greenbelt, MD), is expected to complete the first imaging telescopes ever assembled almost exclusively from 3D-manufactured components. The devices' optics and electronics will be fabricated using conventional methods. "As far as I know, we are the first to attempt to build an entire instrument with 3D printing," says Budinoff. He is building a fully functional 50 mm camera whose outer tube, baffles, and optical mounts are all printed as a single structure. The instrument is appropriately sized for a CubeSat (a small satellite made of individual units each about 100 mm on a side). 

"The experiments involve an oil droplet that bounces along the surface of a liquid. The droplet gently sloshes the liquid with every bounce. At the same time, ripples from past bounces affect its course. The droplet's interaction with its own ripples, which form what's known as a pilot wave, causes it to exhibit behaviors previously thought to be peculiar to elementary particles - including behaviors seen as evidence that these particles are spread through space like waves, without any specific location, until they are measured." Pilot-wave theory reresurrected. Maybe something for the next "fundamental" :P physics RF?

And for the next 'Experimental Physics Stagiaire' position why not try to do "Unpredictable Tunneling of a Classical Wave-Particle Association" http://stilton.tnw.utwente.nl/people/eddi/Papers/PhysRevLett_TUNNEL.pdf, there are some rumors online that the results of Yves Couder Experiments can be reproduced with simple DIY vibrating tables! It is very funny to see the videos of the MIT's replication of this experiment (with lightening legends for those who are uncomfortable with the concepts involved https://www.youtube.com/watch?v=YF5iHQMjcsM)

Nice story telling. (watch the video) The materials are actually cool, but the venus flytrap pitch (hinting at a biomimetic success) or the embodied intelligence speech are "a bit" of a stretch,

Evolutionary Strategies are able to explore broader areas of the search space than reinforcement learning techniques. Thus, they are able to encounter strange bugs resulting in large rewards.

It will be the new hype in a few years when DL is settled....

are we paying more for socially less valued jobs or are "immoral" jobs paying more because of the nature of their work?

"Cast your name into deep space in style!"

Interesting approach, but with 99.9% probability they will miserably fail (at least in terms of their time schedule) simply because the technology is untested. I haven't read the refs (which miss by the way important works of E. Ahedo et al. on magnetic nozzle acceleration by ambipolar effects), but 1. using water means that you produce oxygen radicals which will erode chamber walls (ionisation efficiency is not 100% and experimental tests haven't been performed yet). 2. Electronic excitation (and radiation), rotational excitation, vibrational excitation, and dissociation are all processes which consume energy and reduce ionisation efficiency drastically. 3. It is a miniaturised Helicon thruster. Theoretical analysis probably does not consider near field effects. Far field models are probably not applicable due to the size of the thruster. I expect some surprises during thruster testing. In any case - good luck!

Apparently, there is only one qualification constraint regarding CubeSat propulsion which is related to volatile propellant. Since they use water as propellant and are also the owner of the CubeSat it is actually up to them how they qualify their thruster. Given that it is also possible to qualify the thruster within 18 months - since they define what "qualification" means.

Although vacuum tubes were the basic components of early electronic devices, by the 1970s they were almost entirely replaced by semiconductor transistors. They are now back in nano-form as "nanoscale vacuum channel transistors" that combine the best of vacuum tubes and modern semiconductors into a single device. This old-technology with a new twist could be useful for space applications due to broader temperature operational range and better radiation resilience - authors are with NASA Ames.

"Two sets of [ ATV docking training for astronauts ] lessons are now available for the home user to try." And in case you wonder *where* in the earth are they available, the links are on the right-hand column (also known as ESA's scorn on usability). As usual for the material located there, I took me a few minutes to find them...

Well I tried and could not locate the app to download from these links and sent them a feedback on what I thought a wrong error - though the email bounced :-) So, what is the right link to the app then?

Leo, I'm not iEnabled, so I can't help you with the app. Using other links you can try the PC version (so 20th-century-ish, I know), of course assuming you have somewhere one with Internet Explorer :-)

The International Space Apps Challenge is now over, it is interesting to have a look at the solutions ...

what sort of "app" is this e.g. http://spaceappschallenge.org/challenge/brightest-night/solution/132 "We started of by trying to set our camera in raw mode, howsoever this can't be done for current logitech modules and without a high risk of permanently destroying the camera (reflashing the EEPROM). we use a logitech c920 and captured a raw image from it using guvcview on ArchLinux we then wrote some python code to calculate the average BGR value of our Image. We are currently workin on automiztion, but this will take much longer as there will be a lot of reverse engineering of the USB-Protocol needed."

c'mon really! To name a few: - Tour of the Solar System ... that is one of the numerous specialities of the ACT. - Satellite data correlation tool ... solution is flawed, but I really like the idea. Lot of added value. I definitely think are interestung stuffs to do there for cheap. - Aurora project: Model & Data ... space weather not interesting?! - Kepler ... a classic Do not expect the solutions to be tremendous just after 3 days of work, but the proposed list of challenges are "seeds" for innovation to me.