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love this one ... it seems to take physicist to explain to the AI crowd what they are actually doing ... Deep learning is a broad set of techniques that uses multiple layers of representation to automatically learn relevant features directly from structured data. Recently, such techniques have yielded record-breaking results on a diverse set of difficult machine learning tasks in computer vision, speech recognition, and natural language processing. Despite the enormous success of deep learning, relatively little is understood theoretically about why these techniques are so successful at feature learning and compression. Here, we show that deep learning is intimately related to one of the most important and successful techniques in theoretical physics, the renormalization group (RG). RG is an iterative coarse-graining scheme that allows for the extraction of relevant features (i.e. operators) as a physical system is examined at different length scales. We construct an exact mapping from the variational renormalization group, first introduced by Kadanoff, and deep learning architectures based on Restricted Boltzmann Machines (RBMs). We illustrate these ideas using the nearest-neighbor Ising Model in one and two-dimensions. Our results suggests that deep learning algorithms may be employing a generalized RG-like scheme to learn relevant features from data.

looks like an application of laser filamentation ...

They use a technique they call "Empirical Dynamic Modeling" to find correlations between different variables of chaotic systems. Might be interesting for things like climate modeling and similar chaotic systems. The idea seems pretty straight forward but I never encountered it before - so I'm no sure if this is really a new development (curious if anybody else knows). If you are short on time just watch the video embedded in the article.

Just by reading the page and the related material I didn't really get much, but I think it could be worth investing some time in reading more about it. But I'm interested in this, so I'll try to dig deeper!

Swarm-based fabrication of interwoven composite tubes via a fully autonomous, cooperative system can help create architectural-scale structures in effective and efficient ways, including in remote environments.

A nice merger of different AI technologies. System teaches itself to derive concepts from images and some Q/A-pairs.

The paper I talked about with the proof of a gigantic lava tube discovered in 2017 from data of the Japanese lunar mission

Given the size of this thing we may consider a project on city urban planning inside. I would see a rocket-port outside the crater, some lift systems to get in, a closed dome with artificial atmosphere where to develop the city possible trekking routes on the lunar surface, a mirror system to get sunlight in, an energy factory just outside the entry.

NASA and the Department of Energy's National Nuclear Security Administration (NNSA) have successfully demonstrated a new nuclear reactor power system that could enable long-duration crewed missions to the Moon, Mars and destinations beyond. Main page for kilopower project: https://www.nasa.gov/directorates/spacetech/kilopower

Einstein's theory of gravity, General Relativity (GR), has been tested precisely within the Solar System. However, it has been difficult to test GR on the scale of an individual galaxy. Collett et al. exploited a nearby gravitational lens system, in which light from a distant galaxy (the source) is bent by a foreground galaxy (the lens). Mass distribution in the lens was compared with the curvature of space-time around the lens, independently determined from the distorted image of the source. The result supports GR and eliminates some alternative theories of gravity.

An interesting project that can teach you something about AI training bias. While the system can generate marvelous portraits, it was trained on images displaying not a smiling expression, so it will most likely fail on smiling photos.

encouraging trend

In case you want to ask him anything

The size of this river system might give a hint at the flow rate and in turn on the "methane/ethan"-cycle's strength...

So they think they found a way for beta decay to produce both lighter (Ni->Cu) AND heavier (C->N) nuclei? ...

just another attempt to revive cold fusion from the dead ... and all with dubious experimental setups; read the last phrase ""From my perspective, this is still a physics experiment," Zawodny said. "I'm interested in understanding whether the phenomenon is real, what it's all about. Then the next step is to develop the rules for engineering. Once you have that, I'm going to let the engineers have all the fun." He went on to say that, " All we really need is that one bit of irrefutable, reproducible proof that we have a system that works. As soon as you have that, everybody is going to throw their assets at it. And then I want to buy one of these things and put it in my house."

Bartolomé call's workshop paper ... with some nice words also for the ACT "I want to congratulate the Advanced Concepts Team of the ESA and the Faculty of Mathematics and Physics of Ljubljana for this initiative." congrats Sante and Pacome again!

Asimov's Foundation meets ACT's Tipping Point Prediction?

still, some interesting thoughts in there ... "Then you have the 50-year cycles of violence. Turchin describes these as the building up and then the release of pressure. Each time, social inequality creeps up over the decades, then reaches a breaking point. Reforms are made, but over time, those reforms are reversed, leading back to a state of increasing social inequality. The graph above shows how regular these spikes are - though there's one missing in the early 19th century, which Turchin attributes to the relative prosperity that characterized the time. He also notes that the severity of the spikes can vary depending on how governments respond to the problem. Turchin says that the United States was in a pre-revolutionary state in the 1910s, but there was a steep drop-off in violence after the 1920s because of the progressive era. The governing class made decisions to reign in corporations and allowed workers to air grievances. These policies reduced the pressure, he says, and prevented revolution. The United Kingdom was also able to avoid revolution through reforms in the 19th century, according to Turchin. But the most common way for these things to resolve themselves is through violence. Turchin takes pains to emphasize that the cycles are not the result of iron-clad rules of history, but of feedback loops - just like in ecology. "In a predator-prey cycle, such as mice and weasels or hares and lynx, the reason why populations go through periodic booms and busts has nothing to do with any external clocks," he writes. "As mice become abundant, weasels breed like crazy and multiply. Then they eat down most of the mice and starve to death themselves, at which point the few surviving mice begin breeding like crazy and the cycle repeats." There are competing theories as well. A group of researchers at the New England Complex Systems Institute - who practice a discipline called econophysics - have built their own model of political violence and

It's not the scientific activity described in the article that is uninteresting, on the contrary! But the way it is described is just a bad joke. Once again the results itself are seemingly not sexy enough and thus something is sold as the big revolution, though it's just the application of the oldest scientific principles in a slightly different way than used before.

The Robobee takes off without guide wires! It is still powered via a wire, and the control is done with the help of a VICON system and on an external computer, but this still is an amazing feat!

The way they make this thing is just as impressive. The manufacturing technique is "pop-up book" folding, a method that has been developed by the same group and that allows a two dimensional monolithic MEMS structures to be easily assembled into a 3D structure. I actually put this as an item of the "Technology List 2020" on the wiki this morning.

I agree, manufacturing is the amazing thing here ..... as soon as the power-consumption/density problem is solved these things will really take off :)

remember our recent discussion about this?

The French Space Agency (CNES) commissioned Damien Labrousse to recreate the Jupiter Mission Control Room in Lego for display at the Kourou spaceport. The impressive build features 6,000 bricks, 80 minifigs, a working video screen that shows the rocket launch sequence and a sound system, displaying launch countdown.

The Rayleigh criterion specifies the minimum separation between two incoherent point sources that may be resolved into distinct objects. Here, a strategy to break the limits of this criterion for the first time, some small allusion to telescopic systems.

Can it also be applied for infrared imagery?

Yesterday [11th May], the Defense Advanced Research Projects Agency (DARPA) held a Demo Day for the Department of Defense in the courtyard at the center of the Pentagon to give the defense community "an up-close look at the Agency's diverse portfolio of innovative technologies and military systems at various stages of development and readiness."