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TED is sponsoring an A.I. XPRIZE. The goal? Develop an artificial intelligence that jumps on stage and gives a 3min talk on a random topic...

I am going to propose that the rules include in addition something practical - like washing the dishes... If we are to foster progress, let's finally do so in the right direction...

This sort of reminds me of Hinton's paper from some years ago: http://www.cs.utoronto.ca/~ilya/pubs/2011/LANG-RNN.pdf Train it on previous TED talks and let it run TED talk - like gibberish. It would probably be of similar value. He had a nice one on the meaning of life but I can't find it anymore.

Awesome! Origami finally got useful! :-D

We made it to Slashdot's frontpage !!! :)

Congratulations, gentlemen!

"When a control laser is fired at the crystal, a complex quantum-level reaction turns it the opaque crystal transparent. A second light source is beamed into the crystal before the control laser is shut off, returning the crystal to its opaque state. This leaves the light trapped inside the crystal, and the opacity of the crystal keeps the light trapped inside from bouncing around, effectively bringing light to a full stop." is the simple explanation, but I am not sure how this is actually possible with the current laws of physics

There are two ways to make slow light: material slow light and structural slow light, where you either change the material or the structural properties of your system. Here they used EIT to make material slow light, by inducing transparency inside an otherwise opaque material. As you change the absorption properties of a material you also change its dispersion properties, the so-called Kramers-Kronig relations. A rapid positive change in the dispersion properties of a material will give rise to slow light. To effectively stop light they switched off the control beam, bringing back the opaque state. Another control beam is then used to retrieve the probe pulse that was 'frozen' inside the medium. Light will be halted according to the population lifetime on the energy level (~ 100s). They used an evolutionary algorithm to find an optimal pulse preparation sequence to reach close to the maximum possible storage duration of 100s. Interesting paper!

So it is not real storage then in a sense, as you are stimulating an excitation population which retains the phase information of your original pulse? Still it is amazing that they could store this up to 100s and retrieve it with a probe pulse, but light has never been halted.

Black-body radiation can give rise to a net attractive force between tiny objects. That is the claim made by physicists at the University of Innsbruck in Austria, who have calculated the strength of this new force between a speck of dust and a hydrogen atom. Under some cirmustances this force could be stronger than gravitation. Read the paper here: http://prl.aps.org/abstract/PRL/v111/i2/e023601

The paper: Mass and motion of globulettes in the Rosette Nebula http://www.aanda.org/articles/aa/abs/2013/07/aa21547-13/aa21547-13.html

why am I not surprised .....

http://www.academia.edu/4210419/Can_climate_models_explain_the_recent_stagnation_in_global_warming A view of well-respected scientists on how to proceed from here, that was rejected from Nature. In any case, a long way to go...

unfortunately it's too early to cheer and burn more coal ... there is also a nice podcast associated to this paper from nature Recent global-warming hiatus tied to equatorial Pacific surface cooling Yu Kosaka & Shang-Ping Xie Nature 501, 403-407 (19 September 2013) doi:10.1038/nature12534 Received 18 June 2013 Accepted 08 August 2013 Published online 28 August 2013 Despite the continued increase in atmospheric greenhouse gas concentrations, the annual-mean global temperature has not risen in the twenty-first century1, 2, challenging the prevailing view that anthropogenic forcing causes climate warming. Various mechanisms have been proposed for this hiatus in global warming3, 4, 5, 6, but their relative importance has not been quantified, hampering observational estimates of climate sensitivity. Here we show that accounting for recent cooling in the eastern equatorial Pacific reconciles climate simulations and observations. We present a novel method of uncovering mechanisms for global temperature change by prescribing, in addition to radiative forcing, the observed history of sea surface temperature over the central to eastern tropical Pacific in a climate model. Although the surface temperature prescription is limited to only 8.2% of the global surface, our model reproduces the annual-mean global temperature remarkably well with correlation coefficient r = 0.97 for 1970-2012 (which includes the current hiatus and a period of accelerated global warming). Moreover, our simulation captures major seasonal and regional characteristics of the hiatus, including the intensified Walker circulation, the winter cooling in northwestern North America and the prolonged drought in the southern USA. Our results show that the current hiatus is part of natural climate variability, tied specifically to a La-Niña-like decadal cooling. Although similar decadal hiatus events may occur in the future, the multi-decadal warming trend is very likely to continue with greenhouse gas

And the actual paper link with some graphs: http://www.sciencedirect.com/science/article/pii/S1053810012000037

Maybe of interest for those into innovative disruption etc? ;)

I could not detect the "disruptive innovation" in the paper

Does this have implications for AI algorithms??

I was actually thinking exactly about this question during my bike ride this morning. I am surprised that some codons would need to have a double meaning though because there is already a surplus of codons to translate into just 20-22 proteins (depending on organism). So there should be about 44 codons left to prevent translation errors and in addition regulate gene expression. If - as the article suggests - a single codon can take a dual role, does it so in different situations (needing some other regulator do discern those)? Or does it just perform two functions that always need to happen simultaneously? I tried to learn more from the underlying paper: https://www.sciencemag.org/content/342/6164/1367.full.pdf All I got from that was a headache. :-\

Probably both. Likely a consequence of energy preservation during translation. If you can do the same thing with less genes you save up on the effort required to reproduce. Also I suspect it has something to do with modularity. It makes sense that the gene regulating for "foot" cells also trigger the genes that generate "toe" cells for example. No point in having an extra if statement.

TU Delft researchers have developed the DelFly Explorer, the world's first Micro Air Vehicle with flapping wings that can avoid obstacles by itself. The uniqueness of this achievement lies in the DelFly Explorer's very low weight (20 grams, i.e. a few sheets of paper), and this opens up new possible applications for both smaller and larger MAVs.

I'm kinda curious what you used for processing power there. Is that a DSP?

The solutions show light tied in knots

Really cool topic. Here a link to a paper from Leiden's quantum optics group from 2008 about knotted light (I was in that group at the time): http://www.nature.com/nphys/journal/v4/n9/abs/nphys1056.html

knot theory ... any volunteers?

New form of locomotion found in spiders. They say it could be used for a robot on Mars...don't immediately see how though. :)

True Marek :) The article does quote a Journal Paper though ..... published in zootaxa: a staggering 0.9 impact factor journal!! And watching the video you immediately understand why :)

I of course watched the video and have trouble sleeping since.

The device, like dolphins, sends out two pulses in quick succession to allow for a targeted search for semiconductor devices, cancelling any background "noise",

Could it be used to measure ocean acidification? I found a study that links sound wave propagation with ocean acidity. Maybe we are able to do such measurement from space even? "Their paper, "Unanticipated consequences of ocean acidification: A noisier ocean at lower pH," published last week in the journal Geophysical Research Letters, found that fossil fuels are turning up the ocean's volume. Since the beginning of the Industrial Revolution, the overall pH of the world's oceans has dropped by about 0.1 units, with more of the changes concentrated closer to the poles. The authors found that sound absorption has decreased by 15 percent in parts of the North Atlantic and by 10 percent throughout the Atlantic and Pacific"

The last time I asked an oceanographer for the use of acoustic waves, she said it is still a bit problematic method to take into account its data, but we were referring to measuring ocean circulation. It may be more conclusive for PH measurements, though. The truth is that there is a whole underwater network with pulse emmitters/receivers covering the North Atlantic basin, remnant infrastructure for spying activities in the WW2 and in the cold war, that stays unexploited. We should look more into this idea

In order to overcome the communication blackout problem suffered by hypersonic vehicles, a matching approach has been proposed for the first time in this paper. It utilizes a double-positive (DPS) material layer surrounding a hypersonic vehicle antenna to match with the plasma sheath enclosing the vehicle. Or in more easy language, basically one provides an antenna as capacitor, in combination with the plasma sheath (an inductor), they form an electrical circuit which becomes transparent for long wavelength radiation (the communication signal). The reasons is that fluctuations are balanced by the twin system, preventing absorption/reflection of the incoming radiation. Elegant solution, but will only work on long wavelength communication, plus I am not sure whether the antenna needs active control (as the plasma sheath conditions change during the re-entry phase).

"Edward Snowden papers unmask close technical cooperation and loose alliance between British, German, French, Spanish and Swedish spy agencies" - I thought we were the good guys... ;-D

Nature paper by HP Labs: they use waveguides to produce a 3D wide-angle glasses-free image. Here's there website: http://h30507.www3.hp.com/t5/Innovation-HP-Labs/On-Our-Way-to-Glasses-Free-3D/ba-p/134391#.UcFSSOdgfTo

Strange that this article is based on the 2001 paper that furthermore was subseded by another one of the same authors from 2006 but not mentioned.

Time is an emergent phenomenon that is a side effect of quantum entanglement, say physicists. And they have the first exprimental results to prove it

I guess I tentatively agree with you on both points. In the end there might anyway be surprisingly little overlap between the way that we describe what nature does and HOW it does it... :-D

Congratulations! 100% agree.

Both graphene and 3d printing has been around for quite a while, but combined they could provide unique properties of materials, eg in the use of high performance 3d batteries. This paper gives a nice overview of what has been done in the field up to now.