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Basically quantum entanglement, or more accurately the dispersal and expansion of mixed quantum states, results in an apparent flow of time. Quantum information leaks out and the result is the move from a pure state (hot coffee) to a mixed state (cooled down) in which equilibrium is reached. Theoretically it is possible to get back to a pure state (coffee spontaneously heating up) but this statistical unlikelihood gives the appereance of irreversibility and hence a flow o time. I think an interesting question is then: how much useful work can you extract from this system? (http://arxiv.org/abs/1302.2811) It should for macroscopic thermodynamic systems lead to the Carnot cycle, but on smaller scales it might be possible to formulate a more general expression. Anybody interested to look into it? Anna, Jo? :)

What you propose is called Maxwell's demon: http://en.wikipedia.org/wiki/Maxwell%27s_demon Unfortunately (or maybe fortunately) thermodynamics is VERY robust. I guess if you really only want to harness AND USE the energy in a microscopic system you might have some chance of beating Carnot. But any way of transferring harvested energy to a macroscopic system seems to be limited by it (AFAIK).

Check the landing video from the onboard camera - Guido: how well would our optical flow algorithm cope with such images? Looks quite complicated to me....

Note that videos there are said to be "thumbnail" quality, so I think videos with higher resolution (and possibly frame rate) have been acquired, just that they were not downloaded yet.

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 .

addressing some of the fundamentals of particle flow in air ...

Doesn't really sound sexy, but this is of utmost importance for next generation grids for renewable energy.

I agree on the significance indeed - a small boost also for my favourite Desertec project ... Though their language is a bit too "grandiose": "ABB has successfully designed and developed a hybrid DC breaker after years of research, functional testing and simulation in the R&D laboratories. This breaker is a breakthrough that solves a technical challenge that has been unresolved for over a hundred years and was perhaps one the main influencers in the 'war of currents' outcome. The 'hybrid' breaker combines mechanical and power electronics switching that enables it to interrupt power flows equivalent to the output of a nuclear power station within 5 milliseconds - that's as fast as a honey bee takes per flap of its wing - and more than 30 times faster than the reaction time of an Olympic 100-meter medalist to react to the starter's gun! But its not just about speed. The challenge was to do it 'ultra-fast' with minimal operational losses and this has been achieved by combining advanced ultrafast mechanical actuators with our inhouse semiconductor IGBT valve technologies or power electronics (watch video: Hybrid HVDC Breaker - How does it work). In terms of significance, this breaker is a 'game changer'. It removes a significant stumbling block in the development of HVDC transmission grids where planning can start now. These grids will enable interconnection and load balancing between HVDC power superhighways integrating renewables and transporting bulk power across long distances with minimal losses. DC grids will enable sharing of resources like lines and converter stations that provides reliability and redundancy in a power network in an economically viable manner with minimal losses. ABB's new Hybrid HVDC breaker, in simple terms will enable the transmission system to maintain power flow even if there is a fault on one of the lines. This is a major achievement for the global R&D team in ABB who have worked for years on the challeng

So... who is in?

nice comment Johannes ... if you add a bit of Kleopatre, e.g. why bathing in milk helped her fool Marcus Antonius, your comment would be fully interdisciplinary :-)

you mean it would include History or Psychology? I would understand why Marcus Antonius might get fooled by a bathing beauty - but milk? DONKEY MILK?!? That's just wrong... :-[

While humans have been writing for at least 5000 years, we have surprisingly little understanding of the physics underlying how ink moves from pen to paper. Now, physicists in South Korea and the US have worked out a theory - backed by experiment - that suggests the ink's flow rate depends on a tug-of-war that is played out between the capillary properties of pen and paper.

HIRISE (High Resolution Imaging Science Experiment) images show flows lengthen and darken on rocky equator-facing slopes from late spring to early fall. The seasonality, latitude distribution and brightness changes suggest a volatile material is involved, but there is no direct detection of one.

Thermoelectric materials can see their performance radically improved via the utilization of an array of 'nanoscale pillars,' according to new research from the University of Colorado Boulder. These tiny pillars, built directly onto the thermoelectric material, will reduce the heat flow through the material by a factor of two while not affecting the electrical flow.

no Higgs boson before 2013... and a replacement of 10,000 superconducting magnet connections ! Reminds me of the the gravitational detectors... no detection before an upgrade in 2013...! There are the big announcements to make the cash flow... and reality !

Higgs is almost 81, so he should better invest in his health if he wants the Nobel prize... But who cares, it's another 5 years window where high-energy theorists can produce nonsense with no experimental evidence. They should be happy!

I think Lucas didn't know he would have such an impact in science with Star Wars...!

do you think it could be the dark side of The Force?

what else...?

How about that for an abstract discipline, and I thought CMS was abstract. Sounds great though: Social Innovation Generation: "Social innovation is an initiative, product, process or program that profoundly changes the basic routines, resource and authority flows or beliefs of any social system. Successful social innovations have durability and broad impact. While social innovation has recognizable stages and phases, achieving durability and scale is a dynamic process that requires both emergence of opportunity and deliberate agency, and a connection between the two."

could this also be useful - I doubt so since it seems to use air flow for cooling but don#t really understand the mechanisms ...

A really cool and powerful tool for creating flow diagrams. I particularly like the layout organising algorithms, really nifty. Anyway, it's installed on the smart board computer now and maybe you'd all like it on your computers too.

energy from ocean currents flow. Also energy from wave power in Portugal is mentioned

for Tobi! nice analogy between the threat and the fast responding in human network

Yet another example of "because scientifically accurate title would sound sooo boring".

he new SR-72 will use a turbine-based combined cycle (TBCC) that will employ the turbine engine at lower speeds, and use a scramjet at higher speeds. A scramjet engine is designed to operate at hypersonic velocities by compressing the air through a carefully designed inlet, but needs to be traveling supersonic before it is practical to begin with. So far research projects from NASA, the Air Force and other Pentagon entities have not been able to solve the problem of transitioning from the subsonic flight regime, through hypersonic flight with a single aircraft. Same problem as Reaction Engines is trying to solve, so I am not sure whether they actually cracked it. In any case, nice pictures. Not sure why the exhaust color is purple in color. Its not running on Argon I believe.

Weird article. Intermediate thruster stage (Ramjet) is missing. Scramjet has supersonic combustion and a normal turbine delivers subsonic flows. Even with afterburner - the Scramjet inlet would decelerate the flow down to subsonic velocity with "normal" subsonic combustion. The only thing I can imagine is that the Scramjet stage is bi-functional and covers both, subsonic and supersonic combustion. But the article doesn't say anything about it.

The size of this river system might give a hint at the flow rate and in turn on the "methane/ethan"-cycle's strength...