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As I now work in the Centre for Robotics *and Neuroscience*, here's a story for you. Some highlights: "It sent the iron straight up into his skull and out of the top of his head, landing some 30 metres away. (...) Phineas was unconscious before getting up and riding an oxcart into town with, 'a big bleedin' hole in his head'. (...) although Phineas survived, he was a changed man. Now he was reportedly unreliable, partial to swearing and often making inappropriate remarks." I guess If I were him I'd be a little partial to swearing too.

Apparently you didn't read it... This is a story about how science is born :)

now I did ... :-) just had read your comment ....

breakthroughs vs. accelerated deployment in climate change mitigation technologies.

indeed. puts me in mind of the often reinvented private ACT idea. actually there's a bunch of interesting looking articles on his website. http://www.khoslaventures.com/khosla/papers.html . No sps in the solar one as far as i can tell :) found this bit intriguing too in that, albeit presumably out of context, it doesn't make sense ""The solution to our energy problems is almost the exact opposite of what Khosla says," declares Joseph Romm, who is the editor of Climate Progress, an influential climate blog, and a senior fellow at the Centre for American Progress Action Fund, a think-tank. "Technology breakthroughs are unlikely to be the answer. Accelerated deployment of existing technologies will get you down the cost curve much more rapidly than a breakthrough."" found this seemingly not very well considered piece (to be fair a blog post) by the guy http://climateprogress.org/2010/07/02/is-anyone-more-incoherent-than-vinod-khosla/ . maybe he's written some more convincing stuff in this vein somewhere.

"Mr Khosla (...) is investing over $1 billion of his clients' money in black swans" Well, with his own money his approach might be a little different :-)

Sounds good!

well of course money is trust, and even more loans and credit and even more stock and bond markets. It all represents trust and expectations. However since the first banks 500 years ago and the first loans etc. etc., and as well the fact that bonds and currencies bring down whole countries (Greece lately), and are mainly controlled by large financial centres and (central) banks, banks have always been on the winning side no matter what and that isn't going to change easily. So if you are talking about these new currencies it would be a new era, not just a new currency. So should Greece convert its debt to bitcoins ;P ?

well, from 1936 to 1993 the central bank of france was owned by the state and was supposed to serve the general interest...

China broke ground on its fourth space center Monday, highlighting the country's soaring space ambitions six years after it sent its first man into orbit. - .6.000 people had to be relocated for the construction

> 6.000 people had to be relocated So what? It's less than 0.0005% of the population...

Earth's center

Greenwich could lose its place at the centre of global time if a move to "atomic time" is voted in by the International Telecommunication Union in Geneva in January 2012.

Haha this is really a British article... Already since 1972 we don't use GMT but UTC, which is based on atomic clocks. However British continue to call it GMT... The question is to drop the leap second in UTC, and France is definitely for this change (for scientific motives of course...;) I don't see how this is connected to winter time however... And they shouldn't worry Greenwich is still the beginning of the world with 0 degree longitude !

"the end of GMT as an international standard could accelerate the move to keep British Summer Time into the winter, letting us have lighter evenings." As I understand it, if GMT looses its "prestigious" status, then it would be easier to push through all-year BST in UK.

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 .

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?!

Hundreds of hidden nearby galaxies have been studied for the first time, shedding light on a mysterious gravitational anomaly dubbed the Great Attractor. Despite being just 250 million light years from Earth-very close in astronomical terms-the new galaxies had been hidden from view until now by our own galaxy, the Milky Way. Using CSIRO's Parkes radio telescope equipped with an innovative receiver, an international team of scientists were able to see through the stars and dust of the Milky Way, into a previously unexplored region of space. The discovery may help to explain the Great Attractor region, which appears to be drawing the Milky Way and hundreds of thousands of other galaxies towards it with a gravitational force equivalent to a million billion Suns. Lead author Professor Lister Staveley-Smith, from The University of Western Australia node of the International Centre for Radio Astronomy Research (ICRAR), said the team found 883 galaxies, a third of which had never been seen before. "The Milky Way is very beautiful of course and it's very interesting to study our own galaxy but it completely blocks out the view of the more distant galaxies behind it," he said. Professor Staveley-Smith said scientists have been trying to get to the bottom of the mysterious Great Attractor since major deviations from universal expansion were first discovered in the 1970s and 1980s. "We don't actually understand what's causing this gravitational acceleration on the Milky Way or where it's coming from," he said. "We know that in this region there are a few very large collections of galaxies we call clusters or superclusters, and our whole Milky Way is moving towards them at more than two million kilometres per hour." The research identified several new structures that could help to explain the movement of the Milky Way, including three galaxy concentrations (named NW1, NW2 and NW3) and two new clusters (named CW1 and CW2).