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The main reasons: (1) awareness, people know that a variety of consumer cars exist (2) negative incentives that push people away from gasoline powered cars, eg fuel taxes (3) positive incentives, exemption from road tax, purchase tax and free parking (all temporary) and (4) extensive recharging infrastructure. Other countries have some/all of these elements, but Norway has pushes mostly and the result is that the nissan leaf was the best sold car in September and October, beating all other cars.

If there's anyone who could afford such things, it is Norway... According to http://xkcd.com/980/, Oljefondet (http://en.wikipedia.org/wiki/Government_Pension_Fund_of_Norway) is currently worth nearly as much as US has spent on wars. I mean, all of them together... One of the biggest problems in Norway is what to do with this money without damaging the economy in the long run :-)

true?

Isn't that why systems have a "wait for 15 minutes before trying again" after 3 or 5 wrong guesses? All the brute force in the word can't save you from real-life latency.

Oh, so you haven't heard about diceware yet? http://world.std.com/~reinhold/diceware.html And, of course, a related XKCD...

according to the normal website (http://www.bnsc.gov.uk/): "The UK Space Agency website will officially launch on 1 April 2010. Until then, the BNSC website will be in a state of transition " the guys above i think just take the piss coz theres no official website. Mission statement: TOGETHER WE ARE GOING TO EMBARK ON A JOURNEY INTO SPACE. ..........................THE MISSION IS......MARS................................."

I've just read a blog entry about this on New Scientist, and while the entry itself is not interesting, I learned from it where the UKSA and ESA's UK establishment are going to be based. Answer: it's even more in the middle of nowhere than Plymouth! BTW does anyone (Leo?) know what is the basis on which new ESA establishments locations are chosen (if this info is classified, you can send it on priv ;) [Edit] Esa has released a news item about it... Whatever one can say about the British Space Agency, they certainly have a fantastic logo!

Here's the link related to one of the lunch time discussions. I recommend it to every single one of you. I promise it will be worth your time. If you're lazy, you have a summary here (good stuff also in the references, have a look at them):      Erren TC, Cullen P, Erren M, Bourne PE (2007) Ten Simple Rules for Doing Your Best Research, According to Hamming. PLoS Comput Biol 3(10): e213.

honestly I think that some of these rules actually make sense indeed ... but I am always curious to get a good book recommendation (which book of Copernic would you recommend?) btw Pacome: we are in Paris ... in case you have some time ...

I warmly recommend this book, a bit old but fascinating: The sleepwalkers from Arthur Koestler. It shows that progress in science is not straight and do not obey any rule... It is not as rational as most of people seem to believe today. http://www.amazon.com/Sleepwalkers-History-Changing-Universe-Compass/dp/0140192468/ref=sr_1_1?ie=UTF8&qid=1294835558&sr=8-1 Otherwise yes I have some time ! my phone number: 0699428926 We live around Denfert-Rochereau and Montparnasse. We could go for a beer this evening ?

link to the paper: http://dx.doi.org/10.1038/nsmb.2119 additional info at: http://fold.it/portal/

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cool. It would be very to make a review of interesting photonic properties we could benefit from nature, and the possible use for space. It's nice to see that some structured can already be replicated...! Is there a structure to give angulaer momentum to light ?

nice graphs ... and nice stats

thanks - I was already wondering several times what had happened to this technique that he used at the talk we looked at several times when it was first uploaded ... good that they have made it open source! are they easy to use?

the easiest way to use them is: Google Docs > open/create a spreadsheet > Insert > Gadget > Charts > Motion Chart !! :) You have here a tutorial describing all the steps to get it running.

This is really cool. I know one of the authors and he is a good guy... the only thing that leaves me unsatisfied is that if the whole issue is related to thermal effects one should have seen the Pioneer effect all the time and not only at about 10 AU... ...or is there some thermal process that kicked in only at this distance?

Here's an update on this theory: NASA Releases New Pioneer Anomaly Analysis "The mysterious force acting on the Pioneer spacecraft seems to be falling exponentially. That's a strong clue that on-board heat is to blame, says NASA." Heat emission 'most likely cause' of pioneer anomaly "What's more interesting is that, contrary to the original analysis conducted all those years ago, the deceleration does seem to be decelerating at an exponential rate -- just as one might expect from the radioactive decay of plutonium-238, which powers the two spacecraft. Turyshev concludes, "The most likely cause of the Pioneer anomaly is the anisotropic emission of on-board heat.""

big big booster coming ... !

even bigger booster also coming: China Aims To Build World's Largest Rocket "Back in March, China revealed it is studying the feasibility of designing the most powerful carrier rocket in history for making a manned moon landing and exploring deep space, according to Liang Xiaohong, vice head of the China Academy of Launch Vehicle Technology. The rocket is envisaged to have a payload of 130 tonnes, five times larger than that of China's current largest rocket. This rocket, if built, will eclipse the 53 tonne capacity of the planned Falcon 9 Heavy from SpaceX. It will even surpass the largest rocket ever built, the 119-tonne Saturn V."

still only "is studying the feasibility of designing a powerful carrier rocket" - we could easily do the same at no cost almost ... but still ... they might be serious ...

NASA validates the EmDrive (http://emdrive.com/) technology for converting electrical energy into thrust. (from the website: "Thrust is produced by the amplification of the radiation pressure of an electromagnetic wave propagated through a resonant waveguide assembly.")

I have to join the skeptics on this one ...

Good news for fundamental physics and Earth system science, femtosecond lasers are now about to achieve space qualification thanks to fibre optics!  Applications include high resolution spectroscopy, absolute laser ranging, mapping of the geo-potential and testing of the theory of general relativity to name a few!

nice paper by the Koreans, did not know that they had already such a laser in orbit for a year. How much would this type be upscalable for our needs? in case we have not, we should reference it

Proving the theory of relativity with picosecond lasers, an experiment soon to be installed on the ISS.

An exhaustive overview of all possible advanced rocket concepts, eg.. "As an example, consider a photon rocket with its launching mass, say, 1000 ton moving with a constant acceleration a =0.1 g=0.98 m/s2. The flux of photons with E γ=0.5 MeV needed to produce this acceleration is ~1027/s, which corresponds to the efflux power of 1014 W and the rate of annihilation events N'a~5×1026 s−1 [47]. This annihilation rate in ambiplasma l -l ann corresponds to the value of current ~108 A and linear density N ~2×1018 m−1 thus any hope for non-relativistic relative velocity of electrons and positrons in ambiplasma is groundless." And also, even if it would work, then one of the major issues is going to be heat dispersal: "For example, if the temperature of radiator is chosen T=1500 K, the emitting area should be not less than 1000 m2 for Pb=1 GW, not less than 1 km2 for Pb=1 TW, and ~100 km2 for Pb=100 TW, assuming ε=0.5 and δ=0.2. Lower temperature would require even larger radiator area to maintain the outer temperature of the engine section stable for a given thermal power of the reactor."

The problem is not achieving a high energy density, that we can already do with nuclear fission, the question however is how to confine or harness this power with relatively high efficiency, low waste heat and at not too crazy specific mass. I see magnetic confinement as a possibility, yet still decades away and also an all-or-nothing method as we cannot easily scale this up from a test experiment to a full-scale system. It might be possible to extract power from such a plasma, but definitely well below breakeven so an additional power supply is needed. The fission fragments circumvent these issues by a more brute force approach, thereby wasting a lot of energy for sure but at the end probably providing more ISP and thrust.

Sure. However, the annihilation based photon rocket concept unifies almost all relevant drawbacks if we speak about solar system scales, making itself obsolete...it is just an academic testcase.

love this one ... it seems to take physicist to explain to the AI crowd what they are actually doing ... Deep learning is a broad set of techniques that uses multiple layers of representation to automatically learn relevant features directly from structured data. Recently, such techniques have yielded record-breaking results on a diverse set of difficult machine learning tasks in computer vision, speech recognition, and natural language processing. Despite the enormous success of deep learning, relatively little is understood theoretically about why these techniques are so successful at feature learning and compression. Here, we show that deep learning is intimately related to one of the most important and successful techniques in theoretical physics, the renormalization group (RG). RG is an iterative coarse-graining scheme that allows for the extraction of relevant features (i.e. operators) as a physical system is examined at different length scales. We construct an exact mapping from the variational renormalization group, first introduced by Kadanoff, and deep learning architectures based on Restricted Boltzmann Machines (RBMs). We illustrate these ideas using the nearest-neighbor Ising Model in one and two-dimensions. Our results suggests that deep learning algorithms may be employing a generalized RG-like scheme to learn relevant features from data.

"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)

Einstein's theory of gravity, General Relativity (GR), has been tested precisely within the Solar System. However, it has been difficult to test GR on the scale of an individual galaxy. Collett et al. exploited a nearby gravitational lens system, in which light from a distant galaxy (the source) is bent by a foreground galaxy (the lens). Mass distribution in the lens was compared with the curvature of space-time around the lens, independently determined from the distorted image of the source. The result supports GR and eliminates some alternative theories of gravity.

How do humans construct their mental representations of the passage of time? The universalist account claims that abstract concepts like time are universal across humans. In contrast, the linguistic relativity hypothesis holds that speakers of different languages represent duration differently. The precise impact of language on duration representation is, however, unknown. Here, we show that language can have a powerful role in transforming humans' psychophysical experience of time. Contrary to the universalist account, we found language-specific interference in a duration reproduction task, where stimulus duration conflicted with its physical growth. When reproducing duration, Swedish speakers were misled by stimulus length, and Spanish speakers were misled by stimulus size/quantity. These patterns conform to preferred expressions of duration magnitude in these languages (Swedish: long/short time; Spanish: much/small time). Critically, Spanish-Swedish bilinguals performing the task in both languages showed different interference depending on language context. Such shifting behavior within the same individual reveals hitherto undocumented levels of flexibility in time representation. Finally, contrary to the linguistic relativity hypothesis, language interference was confined to difficult discriminations (i.e., when stimuli varied only subtly in duration and growth), and was eliminated when linguistic cues were removed from the task. These results reveal the malleable nature of human time representation as part of a highly adaptive information processing system.

if you liked the stratos jump you will like this one :-) (apparently it costed them 1100€ to realise)

There can only be one answer to that... http://www.youtube.com/watch?v=YGGxHs02zSs&feature=related [Edit] P.S. No info on how much the production costed...