Physics

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A hypothesis of everything, that is not what I first thought it would be, is what I will present tomorrow at the April 2019 APS conference. Quantum Gravity, finding a way to make general relativity into a quantum theory of some kind, has been the driving mystery of my adult life.  Now, after years of work towards that, a few who have researched the problem think it was the wrong approach.  That instead we should make Quantum Field theory compatible with General Relativity in some way or the other.   Not the other way around. The talk is “Formal Unification of Gravity and…
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The European Commission pays close attention to document the work of the projects that benefited of its funding. With that intent, the AMVA4NewPhysics network has been described, along with its goals, in a 2016 article on the Horizon magazine. And what is this AMwhatchamacallit network anyway? It is a "European Training Network", a joint venture of a dozen research institutes and universities in Europe who, together with a few industrial partners, provide advanced training to Ph.D. students in Physics and Statistics, and does research at the Large Hadron Collider by participating in the CMS…
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It is a bit embarrassing to post here a graph of boring elementary particle signals, when the rest of the blogosphere is buzzing after the release of the first real black hole image from the Event Horizon collaboration. So okay, before going into pentaquarks, below is the image of the black hole at the center of M87, a big elliptical galaxy 54 million light years away. The image above is remarkable on oh so many levels. First of all, it is the first time that a black hole is actually imaged tout court. Of course, black holes do not emit any light (except Hawking radiation, but you cannot see…
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Yes, this is supposedly a particle physics blog, not a machine learning one - and yet, I have been finding myself blogging a lot more about machine learning than particle physics as of late. Why is that? Well, of course the topic of algorithms that may dramatically improve our statistical inference from collider data is of course dear to my heart, and has been so since at least two decades (my first invention, the "inverse bagging" algorithm, is dated 1992, when nobody even knew what bagging was). But the more incidental reason is that now _everybody_ is interested in the topic, and that…
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For the tenth anniversary of this blog being hosted by Science 2.0, which is coming in a few days, I decided to reinstall the habit I once had of weekly picking and commenting on a result from high-energy physics research, a series I called "The Plot Of The Week". These days I am busier than I used to be when this blog started being published here, so I am not sure I will be able to keep a weekly pace for this series; on the other hand I want to make an attempt, and the first step in that direction is this article.The plot of the week is this time a very recent result published by the ATLAS…
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Last Monday and Tuesday I gave a few lectures on Machine Learning at a Data Science school (IDPASC) in Braga, Portugal. I think that this topic has received so much attention in the last few years, with heaps of excellent resources now freely available online, that it is very difficult to be original and provide useful information to any student who is proactive enough to google "auto-encoders" by herself. So what did I have to offer that could be of interest and stimulating to the 80 students who attended the school? I tried to leverage my own background and the personal way of viewing the…
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Update: a reader points out that a similar idea was already proposed and implemented in a commercial program. I'm glad to know this! (I would certainly not try to push my own implementation against a commercial product). I was however disappointed to see that the implementation, while perfectly acceptable from the point of view of quantum mechanics, is lacking in a few important ways from the chess logic point of view (some comments are in the thread below). Anyway, this is an example of a good idea coming too late... Stuck at home with a flu (great!, this way I miss the Neutel 2019…
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What is dark matter (DM)? This is one of the most pressing questions in fundamental science nowadays. We have observed that only one fifth of the matter that exists in the Universe clusters into stars and emits light - the rest appears to only interact gravitationally, producing phenomena we can study through the dynamics of galaxy rotation or by observing the deflection of light passing through it.Since we know that visible matter is made by elementary particles - mostly protons and neutrons!, it is quite natural to make the working assumption that dark matter, too, is made of particles,…
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Nima Arkani-Hamed needs no introduction - he's a superstar theoretical physicist, and whenever he speaks, his colleagues listen - so much so that his seminars regularly overrun twice past their scheduled duration, without anybody blinking.  And today it's your lucky day (and mine), as you get to listen to a clear thinker explaining what really is the status of research in fundamental physics, and why it is actually extremely exciting, much to the discomfort of those who would prefer that public money were spent to reduce taxes (if you don't get the pun, please leave). In a lengthy…
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Today's news is that five months after Alessandro Strumia's controversial talk at a conference on "Theory and Gender", CERN decided to terminate the Italian theorist's status of "guest professor", effectively cutting its ties with him. The decision certainly affects the ability of Strumia to further his research in particle phenomenology, which centered on models of physics beyond the Standard Model, and is rather unprecedented. If you have not followed the story from the beginning, I suppose you can read about it in many online sources (j.f.Google it); if you care for an advice, a…