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they used names of scientists and research centres without these actually knowing about their involvement it seems.... I am wondering what they actually reported back in terms of results? randomly generated papers? Christos?

Hopefully I'm wrong, but I'm very pessimistic. I guess they will impose even more control, ask for even more detailed description of the results that will be delivered and concentrate even more on project funding instead of funding open research.

maybe this is what happen when there is so much paper involved... a simple phone call to one of the research scientist and the fraud is unveiled :) or maybe the "bored project officer" has a brand new mercedes...

very nice article - though a bit long but I am sure that you will also enjoy reading it ....

Short article on the AMS policy statement on geoengineering in US (see also the other bookmark I posted)

very interesting indeed ... we are almost too late :-)

They want so much to reduce the price of the program that they forgot that the ultimate goal is Mars ... cos' this would not be a technology demonstration anymore ... am I wrong ?

Tobias - have a look at this one ... am surprised to see this "new" paper since thought to remember that in our study they presented something quite similar ....

I am sure that Kevin would love this one ... just installed it ... would it work on our ariadnet?

does not sound overly advanced to me - but am not a roboticist ...

What have we been discussing recently? Ok, I am convinced...

In Mac... (who is using it really? have it installed since some time but am not really using it LS)

This is a bibliography management system one of my project partners suggested. I (Tobias) am trying it out in the frame of the project. If you do not hear anything from me, it was probabely not sooo successfull...

NEURO-ENGINEERING COMPUTATIONAL SCIENCES DIVISION NASA AMES RESEARCH CENTER

smells like ariadnet for ariadna papers and researchers

I am on mendeley now and I like it so far ! You can check my page on http://www.mendeley.com/profiles/pacome-delva/

am also on Medelay since some time - think that Tobias has showed it to me. Nice but did not actually use it yet really ....

just discovered this thought cloud alpha stage website .... I am sure that Kevin would LOVE this one ...

could not find any decent paper on this results, but they would be fantastic of course .... though am a bit sceptic

ok found one: doi:10.1038/nmat2635

astonishing! whenever you go to a judge, make sure that he has a full belly ... I am sure we can apply this things also for other situations: exams etc

More funding for helicon double layer. I am wondering how much EADS is contributing to it? Must be Lainé. 

I am quite amazed that they apparently still use the capsules to return the pictures??? Hard to believe .... "Kobalt spacecraft reportedly carry canisters to return film to Earth during the satellite's mission, which will last at least several months."

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 .

Give the Ubermancycle a try?

> As in never ever see sun and daylight :)) Like in the Netherlands you mean?

Tri-phasic sleep rhythm works fine.

my old question: how could we use it for space?

It will depend on the alloys used, I am not sure but bainite might magnetic and I am not sure if nickel alloy based (stainless) steels can be processed at this low temperature... Metallurgist RF?