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Quite intriguing!

this is fantastic! If built, such systems would behave in strange ways, says Achim Rosch, a theoretical physicist at the University of Cologne in Germany, who proposed the technique used by Schneider and his team3. For instance, Rosch and his colleagues have calculated that whereas clouds of atoms would normally be pulled downwards by gravity, if part of the cloud is at a negative absolute temperature, some atoms will move upwards, apparently defying gravity4. Another peculiarity of the sub-absolute-zero gas is that it mimics 'dark energy', the mysterious force that pushes the Universe to expand at an ever-faster rate against the inward pull of gravity. Schneider notes that the attractive atoms in the gas produced by the team also want to collapse inwards, but do not because the negative absolute temperature stabilises them. "It's interesting that this weird feature pops up in the Universe and also in the lab," he says. "This may be something that cosmologists should look at more closely."

If you've ever found your iPhone taking control of your life, there may be a good reason. It may think it has free will. That may not be quite as far-fetched as it sounds. Today, one leading scientist outlines a 'Turing Test' for free will and says that while simple devices such as thermostats cannot pass, more complex ones like iPhones might.

I don't know the inventor of that nonsense that the free will should be the result of QM. It's about the only point I agree with the author of the paper: QM is not necessary and doesn't help. What I meant: all these thought experiments done by typical ultra-naive realists (or ultra-naive physicalists, if you prefer) that cultivate the university departments of physics, computer science etc. are put the cart before the horse. First one has to clarify the role of physical theories and its concepts (e.g. causality) and then one can start to ask how "free will" could perhaps be seen in these theories. More than 200 years ago there existed a famous philosopher named Kant who had some interesting thoughts about this. But authors like Lloyd behave as if he never existed, in fact is view of the world is even pre-Platonic!

Henry Kissinger How I'm missing yer And wishing you were here

Rings of excited atoms that harness a quantum effect to absorb light at an enhanced rate could be used in future technologies such as highly sensitive cameras, solar cells and systems for optical power transmission.

this gets into into interesting power ranges

Horizon2020 project on post quantum cryptography just released their first draft of recommendations for quantum computer safe encryption algorithms. No big surprise with the symmetric algorithms (what's used today is fundamentally sound), but the asymmetric public-key methods will be interesting.

Australian scientists have cleared one of the final hurdles for designing and building a quantum computer. The team of engineers from the University of New South Wales has successfully built a core component needed for the computer to operate and the work is published today in the journal Nature.

Giving the title, I think the comment is not necessary...

Haha, nice article : One of the best-known versions of non-general relativistic quantum versions of time travel comes from Wheeler, as described by Feynman in his Nobel Prize lecture [16]: 'I received a telephone call one day at the graduate college at Princeton from Professor Wheeler, in which he said, "Feynman, I know why all electrons have the same charge and the same mass." "Why?" "Because, they are all the same electron!" And, then he explained on the telephone, "Suppose that the world lines which we were ordinarily considering before in time and space - instead of only going up in time were a tremendous knot, and then, when we cut through the knot, by the plane corresponding to a fixed time, we would see many, many world lines and that would represent many electrons, except for one thing. If in one section this is an ordinary electron world line, in the section in which it reversed itself and is coming back from the future we have the wrong sign to the proper time - to the proper four velocities - and that's equivalent to changing the sign of the charge, and, therefore, that part of a path would act like a positron."

essentially they made an experiment that does not prove or disprove anything -big deal-... what is the scientific value of "strongly disfavour"??? I also like the sentence "most models do not have exact predictions for the energy scale associated with this violation of Lorentz invariance" ... but if this is true WHAT IS THE POINT OF THE EXPERIMENT!!!! God, physics is in trouble ....

hum, null result experiments are not useless !!! there is always the hope of finding "something wrong", which would lead to a great discovery. For the state of theoretical physics (the "no exact predictions" quote), i totally agree that physics is in trouble... That's what happen when physicists don't care anymore about experiments...! All you can do now is drawing "nice"graph with upper bounds on some parameters of an all tunable weird theory !

Interesting compilation of breakthroughs for 2009. Wanna think about a quantum algorithm ?

very ACTish

We did look at making computation powers more efficient from the bio perspective (efficiency of computations in brain). This paper was actually the base for our discussion on a new approsach to computing http://atlas.estec.esa.int/ACTwiki/images/6/68/Sarpeshkar.pdf and led to several ACT internal studies

here is the paper I told you about, on the computational power of analog computing: http://dx.doi.org/10.1016/0304-3975(95)00248-0 you can also get it here: http://www.santafe.edu/media/workingpapers/95-09-079.pdf

Interesting blog maintained by the people from D-Wave, who developed the first commercial quantum computer. The blog presents a python implementation to program the D-Wave and some examples.

Highlights of the year 2009 and 2010 of "Classical and Quantum Gravity". There's an ACT paper among them!

Congrats!