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Tunes U puts the power of the iTunes Store to work for colleges and universities, so users can easily search, download, and play course content just like they do music, movies, and TV shows.

Luca and Tobias - have a look at this ... LS

interesting energy/SPS paper

another energy conversion system... could be very interesting for nuclear power sources and other fields. more details in a few days

the team that won the 900.000$ second prize for the space elevator competition (Noone won the 2mil.$ first prize..) for "laser power beaming" a platform at 1km altitude

seems interesting for web design, not for drupal yet though.. (wordpress is similar to drupal, drupal is a bit more powerful for social nets websites)

still only a few percent of conversion efficiency but very promising since working at reasonably focussing and unpolarised light; they announce the publication of a first design of such a system .... to be followed!! Duncan: you wanna have a closer look at it?

99% house advertising, 1% scientific results. I think this is still a conservative guess... And I'm sure this "completely new" effect that you don't see when "staring at the equations of motion" (doggone, how I love this USish "I-am-better-than-the-rest-of-the-world" jargon) certainly has been predicted at least 50 years ago by some smart USSR researcher!!

what to think about that? spoiling important ressources, smart idea?, and is it really cheap?

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 ...

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 .

where real power sits ...

Hasta la vista, baby. A real-life T-1000, the shape-shifting liquid-metal robot from Terminator 2, is a step closer, thanks to a self-powered liquid metal motor. The device is surprisingly simple: just a drop of metal alloy made mostly of gallium - which is liquid at just under 30 °C - with some indium and tin mixed in.

Jarvis could make it, add a power supply and aquarium and we are off :)

Clean Power November 5th, 2014 by The Scottish renewable energy sector is one of the world's best performing, and new data from WeatherEnergy has shown that October was a "bumper month" for the country, generating more than enough electricity from renewable sources to power the country.

Nature paper showing a new photo-bioelectrochemical cell with a new photon-driven biocatalytic fuel cell method achieving electrical power generation from solar energy.

do you have the pdf?

After the Go, real-time RPG as Hendrik alluded?

A new class of exotic materials could find its way into next-generation technologies that efficiently convert waste heat into electrical current according to new research. Both the exotic materials and the means by which they generate electricity rely on a hybrid of advanced concepts-including string theory combined with black holes combined with cutting-edge condensed matter physics.

Sounds spooky

An international team of scientists led by Liang-shi Li at Indiana University has achieved a new milestone in the quest to recycle carbon dioxide in the Earth's atmosphere into carbon-neutral fuels and others materials.

encouraging trend