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Graph coloring with an infinite number of vertices requires at least 5 colors (compared to the 4-color-theorem).

really really interesting article also referring to a Nature paper called Evolutionary dynamics on graphs

nice graphs ... and nice stats

thanks - I was already wondering several times what had happened to this technique that he used at the talk we looked at several times when it was first uploaded ... good that they have made it open source! are they easy to use?

the easiest way to use them is: Google Docs > open/create a spreadsheet > Insert > Gadget > Charts > Motion Chart !! :) You have here a tutorial describing all the steps to get it running.

TensorFlow is an open source software library for numerical computation using data flow graphs. Nodes in the graph represent mathematical operations, while the graph edges represent the multidimensional data arrays (tensors) communicated between them. The flexible architecture allows you to deploy computation to one or more CPUs or GPUs in a desktop, server, or mobile device with a single API. TensorFlow was originally developed by researchers and engineers working on the Google Brain Team within Google's Machine Intelligence research organization for the purposes of conducting machine learning and deep neural networks research, but the system is general enough to be applicable in a wide variety of other domains as well.

And the interface even looks a bit less retarded than theano

Gephi is an interactive visualization and exploration platform for all kinds of networks and complex systems, dynamic and hierarchical graphs. Runs on Windows, Linux and Mac OS X. Gephi is open-source and free. Learn More on Gephi Platform " Gephi 0.8.1-beta has been released! Discover a new Timeline, dynamic ranking and weighted community detection.

Bitcoin utilizes a peer-to-peer network to issue anonymous payment transactions between different users. Dynamical effects have been found, of which some increase anonymity while others decrease it. Most importantly, several parameters of the Bitcoin transaction graph seem to have become stationary over the last 12-18 months. The implications are discussed.

By pulling raw data from the news and plotting it onto a graph, Sean Gourley and his team have come up with a stunning conclusion about the nature of modern war -- and perhaps a model for resolving conflicts. - really interesting

nice visual graph of US budget ...

... related to the new mathematical proof of emergence of structures in random graphs.

How many shapes can be obtained by folding a paper and applying just one straight cut? You'll be surprised...

"The theorem is that every pattern (plane graph) of straight-line cuts can be made by folding and one complete straight cut. Thus it is possible to make single polygons (possibly nonconvex), multiple disjoint polygons, nested polygons, adjoining polygons, and even floating line segments and points." - So the you can cut any assembly of polygons but not a single curved edge (with a finite number of folds (points don't count)): useless. :-P

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.

ever heard of the Erdős-Bacon number? :-)

and actors probably ask who cares about Erdős :) The network of actors who co-star in movies is a famous one among networks people. Kevin Bacon became famous in that network because of fans of his who could from memory trace the paths of a large number of actors back to him :) see: http://en.wikipedia.org/wiki/Six_Degrees_of_Kevin_Bacon#History If you have you publications in http://academic.research.microsoft.com/, it gives you a nice tool to visualize your graph up to Erdős. Apparently I have a path of length 4, and several of length 5: http://academic.research.microsoft.com/VisualExplorer#36695545&1112639

and for the actors http://oracleofbacon.org/

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

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 !

"The first thing everyone did after seeing the energy graph on the family PC was to turn off the lights". Kind-of we are becoming slaves of the technology. Do we really need a sensor to tell us to turn-off the light when we are leaving the room!?

Google Books measurements of word frequencies on 15 million books (12% of all the books ever published). More about it in:  - Google Opens Books to New Cultural Studies - John Bohannon, Science 2010-12-17 - Slashdot: Google Books Makes a Word Cloud of Human History - http://ngrams.googlelabs.com/info

Intuitive, well documented, and very powerful. A library to keep an eye on. Check the example Belgian elections, June 13, 2010 - Twitter opinion mining

A really cool and powerful tool for creating flow diagrams. I particularly like the layout organising algorithms, really nifty. Anyway, it's installed on the smart board computer now and maybe you'd all like it on your computers too.

new open source tool from google .... Francesco: of any interest to us?

I don't think so, it is just a code optimizer for JavaScript, unless there are somewhere big JavaScript (web2.0) applications running that is not of much interest for us Other google labs systems e.g. FriendConnect could be useful for Ariadnet, maybe also the visualization and social graph API

and it seems to have some rather big flaws: http://www.pheedcontent.com/click.phdo?i=6a00fd034f6a8cf464e2d9fbb83dc321