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Tag: phase transition

Modeling the Future: Tools from Complex Systems

Modeling the Future: Tools from Complex Systems

2012 and Beyond: Tools for Predicting the Next Sixty Years Is the world coming to an end on Dec. 21st, 2012, or not? Very likely, not. We’ll still wake up in the morning, in the same beds in which we went to sleep in the night before. We’ll still walk out to our cars, or get to our Metro stations, on time. And we’ll likely stop for the same “cup of joe” on the way to work. But will our…

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Modeling Trends in Long-Term IT as a Phase Transition

Modeling Trends in Long-Term IT as a Phase Transition

The most reasonable model for our faster-than-exponential growth in long-term IT trends is that of a phase transition. At a second-order phase transition, the heat capacity becomes discontinuous. The heat capacity image is provided courtesy of a wikipedia site on heat capacity transition(s). L. Witthauer and M. Diertele present a number of excellent computations in graphical form in their paper The Phase Transition of the 2D-Ising Model. There is another interesting article by B. Derrida & D. Stauffer in Europhysics…

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Gibbs Free Energy, Belief Propagation, and Markov Random Fields

Gibbs Free Energy, Belief Propagation, and Markov Random Fields

Correspondence Between Free Energy, Belief Propagation, and Markov Random Field Models As a slight digression from previous posts – re-reading the paper by Yedidia et al. on this morning on Understanding Belief Propagation and its Generalizations – which explains the close connection between Belief Propagation (BP) methods and the Bethe approximation (a more generalized version of the simple bistate Ising model that I’ve been using) in statistical thermodynamics. The important point that Yedidia et al. make is that their work…

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What Makes a Metastable State Happen?

What Makes a Metastable State Happen?

Metastable States – the Meltdown Precursors I’ve just read a recent column by JL, one of the editors from Taipan Daily. He states, in his column “There Will Be Blood in Europe”: Stepping back a bit: What is so frightening right now, not just in Europe but China and America and Japan too, is the presence of fraud-fueled “Lehman 2.0” catalysts threatening to explode. One could say that the 2008 financial crisis was the mother of all wake-up calls. But…

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"What is X?" – Modeling the Meltdown

"What is X?" – Modeling the Meltdown

“What is X?” – Modeling the 2008-2009 Financial Systems Meltdown We’re about to start a detailed walkthrough of applying a “simple” statistical thermodynamic model to the Wall Street players in the 2007-2009 timeframe. The two kinds of information that I’ll be joining together for this will be a description of Wall Street dynamics, based largely on Chasing Goldman Sachs (see previous blogposts for link), and the two-state Ising thermodynamic model that I’ve been presenting over the past several posts. The…

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Modeling Nonlinear Phenomena

Modeling Nonlinear Phenomena

Modeling Nonlinear Phenomena – What is “X”? Many of us grew up hating word problems in algebra. (Some of us found them interesting, sometimes easy, and sometimes fun. We were the minority.) For most of us, even if we understood the mathematical formulas, there was a big “gap” in our understanding and intuition when it came to applying the formulas to some real-world situation. In the problem, we’d be given a set of statements, and then told to find “something.”…

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Accelerating Change – A Good Read

Accelerating Change – A Good Read

Writing to you within hours of summer solstice, 2010 – we now have 2 1/2 years (approximately) to the time that has been targeted by multiple cultures as a “pivot point” in human experience. The idea that we are accelerating in our experience on this planet is not new. Right now, this idea is receiving a great deal of attention – too much of which is “acceleration” of emotional content, and not an objective assessment. In this sense, John Smart’s…

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