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Physicists working on the LHCb experiment at the CERN particle-physics lab have released the best evidence yet for direct charge-parity (CP) violation in charm mesons....While more data must be analysed to confirm the result, the work could point to new physics beyond the Standard Model and help physicists understand why there is more matter than antimatter in the universe.

lot of new physics this year ...

News about the warp drive based on the original Alcubierre metric but with modified shape function. Focus of the reserach was on the interaction between warp bubble and cosmic particles. Result: People on board need shielding. People at the journey's destination might get roasted (by Gamma rays if you want to know).

Not really the first time, but they seem to be much closer to be being able to study them. Apparently, they had 38 atoms trapped for miliseconds. Now it's time to prove it behaves just like matter.

Interesting... however to me it looks like they have only shifted the problem... instead of looking for WIMPS now we look for X and Y and Phi...

"things are simple if you don't have to check facts" --> the examples are numerous, e.g. mind and matter, cradle-to-cradle

Francesco pointed out this research one year ago, we dropped it as noone was really considering it ... but in space a low CPU power consumption is crucial!! Maybe we should look back into this?

I don't remember what is the speed factor, but I guess this might do it! Although, I remember when using an IMU that you cannot have the data above a given rate (e.g. 20Hz even though the ADC samples the sensor at a little faster rate), so somehow it is not just the CPU that must be re-thought. When I say qualification I also imply the "hardened" phase.

I don't know if the (promised) one-order-of-magnitude improvements in power efficiency and performance are enough to justify looking into this. For once, it is not clear to me what embracing this technology would mean from an engineering point of view: does this technology need an entirely new software/hardware stack? If that were the case, in my opinion any potential benefit would be nullified. Also, is it realistic to build an entire self-sufficient chip on this technology? While the precision of floating point computations may be degraded and still be useful, how does all this play with integer arithmetic? Keep in mind that, e.g., in the Linux kernel code floating-point calculations are not even allowed/available... It is probably possible to integrate an "accelerated" low-accuracy floating-point unit together with a traditional CPU, but then again you have more implementation overhead creeping in. Finally, recent processors by Intel (e.g., the Atom) and especially ARM boast really low power-consumption levels, at the same time offering performance-boosting features such as multi-core and vectorization capabilities. Don't such efforts have more potential, if anything because of economical/industrial inertia?

a nice review on the wonders of Hierarchical Bayesian models. It cites a paper on probabilistic programming languages that might be relevant given our recent discussions. At Hippo's farewell lunch there was a discussion on how kids are able to learn something as complex as language from a limited amount of observations, while Machine Learning algorithms no matter how many millions of instances you throw at them, don't learn beyond some point. If that subject interested you, you might like this paper.

Had an opportunity to listen to JBT and TLG during one summer school.. if they're half as good in writing as they are in speaking, should be a decent read...

dark matter :-) ?? could there be loads of them?

See Also: Matter & Energy Nanotechnology Optics Physics Materials Science Graphene Organic Chemistry Reference White gold Electromagnetic radiation Nanomedicine Nanoparticle Any use for the smell project? "We have demonstrated resonant antenna-enhanced single-particle hydrogen sensing in the visible region and presented a fabrication approach to the positioning of a single palladium nanoparticle in the nanofocus of a gold nanoantenna,"

Oxford University scientists find that a complex skill such as juggling causes changes in the white matter of the brain. - Let's start juggling for the ideastorm!

cool. I can do some lessons with three and four balls... tomorrow after lunch !

for those interested in soft matter, which may be a future topic of the ACT ....

Programmable matter - another nice title for an ACT project...

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 !!!

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 .

Nice paper and linked to so many other factors.... curious "The question of whether mean body temperature is changing over time is not merely a matter of idle curiosity. Human body temperature is a crude surrogate for basal metabolic rate which, in turn, has been linked to both longevity (higher metabolic rate, shorter life span) and body size (lower metabolism, greater body mass). We speculated that the differences observed in temperature between the 19th century and today are real and that the change over time provides important physiologic clues to alterations in human health and longevity since the Industrial Revolution."

Yes, I agree, slime belongs to soft matter.