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Charlotte Moser on Data Assimilation

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My comment : There is this 2000 paper "Information theory explanation of the fluctuation theorem, maximum entropy production and self-organized criticality in non-equilibrium stationary states" by Roderick C. Dewar which is really insightful, I think, but I found it quite hard to understand at first. He deals with the problem of defining what are the parameters of the macroscopic model without referring to any details of the microscopic system: so the reproducible macroscopic behaviour is described entirely in terms of expectation values on the underlying distributions in phase space.  The problem is that in a weather forecast it is not even clear what temperature/humidity could mean at the level of even a 10x10x10cm cube of air. So the idea of the accuracy of the measurements is kind of redundant since we have no way to even say what accuracy means!  See  Lyapunov Stability in Dynamical Systems  and  these other posts of mine .   Subscribe to Charlotte Mo...
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Physics, Self Reference and Self Consciousness

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The muppets at 5:24 : Subscribe to  Oz Harms . See George Ellis and Ard Louis on top-down causation in  Why is Physics So Difficult? It seems like real life only because we know what it is supposed to be like:  And we know it ends well, ... Subscribe to Secondhand Movie Company . This post is a sequel to  About Logic - Is Mathematics a Story? What is a dependent type? What is a judgement? There's one missing, isn't there? What is a dependent judgement then? It's a judgement about a judgement, because it includes the turnstile. So how do you construct one? 21:06 . All these judgements are hypothetical : they depend upon some actual construction of the contexts Г in which they are valid, just like real life .  11:15 .   See the full list of talks here .  The two texts referred to ( 17:10 ): The HoTT Book, a.k.a. Homotopy type theory: Univalent foundations of mathematics . Introduction to Homotopy Type Theory by Egbert Rijke. Subscribe to  EPIT Spri...
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Colleen Fazio Made a New Amp for Sale

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See  https://www.fazioelectric.com/amps . Subscribe to Fazio Electric . 
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DemistifySci Podcast on Making Sense of Physics

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It's an interesting discussion. Get their book via  this stripe link .  Some comments: 1:28:06  On bodies and their actions. Someone mentioned batteries storing electrons and Shilo compared that idea to the one that ovens store heat. Ovens and batteries are things physicists actually used to abstract concepts like electric charge and thermal energy and their relationships like the heating effect of resistance to charge flow. All of that phenomenological physics was done without positing any fundamental carriers of heat or charge. In terms of bodies and their actions you can explain an oven in terms of a cold body being put in contact with a hot one and the action being an increase of temperature of the cold body and a decrease in that of the hot one. One can then relate temperature and electric current using thermocouples, say. Then one can abstract the notion of a current source at a certain potential and call that body a chemical battery (copper and zinc electrodes in a...
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Glenn Diesen and Academy of Ideas on Two Ways to Find Meaning in Life

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Subscribe to Judge Napolitano .     Subscribe to Academy of Ideas .
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About Logic - Is Mathematics a Story?

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They're threatening to do this weekly, ... My comment :  Looking forward to the Dana Scott interview! Maybe there's not time to do this before then, but I would like to hear a discussion about the different views people have about models. I sometimes think that Computer scientists look for models in the zoo of mathematical theories, because they feel like this the only possible source of their legitimacy: they say something like "Well, this type system is sound because if it wasn't then ZFC would be inconsistent and you would have much bigger things to worry about than the soundness of my little type system!" But then serious mathematicians who have Fields medals come along and say "Well actually, I have these proofs that I've done in Higher Homotopy theory and I seriously doubt anyone has checked them as carefully as I did, and I am not sure that I haven't made a mistake somewhere, ..." and then they find a type system that a computer scientist ...
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System Fω and Total Functional Programming

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See  Breaking through the normalization barrier: a self-interpreter for f-omega  (POPL 2016) by Matt Brown and Jens Palsberg. Here's his earlier  video about System-F .  Subscribe to Computable Secrets . Jeremy Gibbons on his book Functional Programming Patterns   See his piece How Design Co-programs .  Why is so hard to get anyone to talk about the dual notion which is data representation by processes? If data determines algorithms, then algorithms can equally well determine data. And if those algorithms are distributed computations then it makes the data they represent very hard to alter. If you ask a computer scientists they might just say "Well, that's because they're not isomorphic." But that doesn't matter: it just means that codata can represent so-called uncomputable functions, which can actually be used in practical applications such as forward key-generation. Some physicists also don't seem to want to think about what data actually is. See  J...
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Desert Living in Arizona and Texas

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  Subscribe to Grow Tree Organics . Subscribe to Crime Pays but Botany Doesn't . Subscribe to Dustups . Part 2: Subscribe to Symbiosys TX .
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Kim Iversen talking with Mel K about her book Infiltration Instead of Invasion

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See  https://themelkshow.com/  and https://rumble.com/c/KimIversen/livestreams . Subscribe to Kim Iversen .   
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Aci-Fi Short - My Only Friend is a Robot Named Beans

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  Subscribe to Dust and Anika Kan Grevstad .
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