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Excellent photo gallery.

Thanks for sharing! Most pics are very very nice, but a few are actually pretty mediocre I must say... "Wildlife" photography is always a rather tricky topic, as demonstrated by this famous story: http://news.bbc.co.uk/1/hi/8470962.stm

Some more stuff: http://www.bbc.co.uk/nature/15359263

BEAUTIFUL! Cassini images are always amazing...

Mortality rates in several Mediterranean countries decline in September, due in part to environmental factors but possibly linked to summer vacations. - What does this teach us?

sleeping and driving on the highway

"The lead vehicle would be handled by a professional driver who would monitor the status of the road train. Those in following vehicles could take their hands off the wheel, read a book or watch TV, while they travel along the motorway. Their vehicle would be controlled by the lead vehicle." .... what or who is defining a professional driver? one of the always overly tired truck drivers?

Anyone out there still doing propulsion stuff? Two more papers just waiting to get busted... http://arxiv.org/abs/0908.1429v1 http://arxiv.org/abs/0908.1803

One reply to Pacome, though the discussion exceeds by far the relevance of the topic already. Baryonic DM is strictly limited by cosomology, if one believes in these models, of course. Anyway, even though most DM is cold, we are constantly bombarded by some DM particles that come together with cosmic radiation, solar wind etc. etc. If DM easily interacted with normal matter, we would have found it long ago. In the paper they consider DM as neutralinos, which are neither baryonic nor strongly or electromagnetically interacting.

well then I agree, how the fu.. they want to collect them !!!

what's your take on these ...

Most important news: Kurzweil postponed his Singularity to 2054. I think this is the postponed postponement of the postponed postponement. Perhaps it will happen shortly after the experimental proof of the existence of the hydrino state and of antigravity in rotating superconductors...

Singularity is like fusion and commercial space travel: always 50 years away.

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 .

Other possible study: get a textbook example of an image of a pen, evolve it just enough so NN can't recognize it anymore, while minimizing the distance between the original and evolved images. EDIT: Its been done already: http://cs.nyu.edu/~zaremba/docs/understanding.pdf

Of course, you can't really use them to extrapolate. The unknown unknown is always the trickiest :P They should just make another class "random bullshit", really and dump all of this stuff in there. I think there's a potential paper right there

Probably old news by now, but this thing sounds so awesome it warrants an entry

Looks like fun! Note though, I'm always slightly annoyed when people use holography only because it sounds cool. because clearly this is not a hologram! Definition: a three-dimensional image formed by the interference of light beams from a laser or other coherent light source. I am sure this is not what is happening in these goggles.

I think they suspect that "hologram" would sell better than "yet-another-augmented-reality-goggle"

In a work published on Nature (http://www.nature.com/nature/journal/v517/n7536/full/nature14090.html#affil-auth) a new DFT based simulation of convection in Earth's Core iron shows that electron-electron scattering has a similar contribution to electron's thermal vibration. The outcome is that using the old dynamo theory the simulation matches the Earth magnetic field experimental results, solving an 80 years old puzzle.

Yay to science! I'm always intrigued by related experiments that try to measure material properties at the GPa range. Especially, the efforts of reaching 'metallic hydrogen' (http://en.wikipedia.org/wiki/Metallic_hydrogen), requiring pressures above 25GPa at which hydrogen becomes conductive. It is thought that gas giant planets could have such a core, but no-one has been able to produce/verify this theory as off yet.

A new study from Harvard reveals that open plan offices decrease rather than increase face-to-face collaboration.

I vote for a silent booth for everyone in ACT

Great study! If something goes wrong Leo and Dario could always blame the "open office".

Not new, but always good to read: British intelligence recommend not having password expiry dates. Something we should apply at ESA!

I second that. It has been an open secret for long though that frequent password changes are creating more problems than they solve. See Bruce Schneier: https://www.schneier.com/blog/archives/2016/08/frequent_passwo.html