Posts

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...

Glenn Diesen and Academy of Ideas on Two Ways to Find Meaning in Life

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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 ...

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...

Desert Living in Arizona and Texas

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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 .   

Aci-Fi Short - My Only Friend is a Robot Named Beans

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Terence Tao on How to Use AI Responsibly

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1:06:18 He's a Taoist, ... I suppose that shouldn't be a surprise. Subscribe to European Mathematical Society . 

Jetbundle - Groups, Monoids, Homomorphisms and Vibes, ...

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Here's the whole blackboard: I had to time-travel to get that picture, so please look at it! My comment : This is great material you're presenting, but the tech you're using is several steps back from a chalkboard or a pen and a piece of paper. I need to see what's been written to be able to refer back to definitions when you use them later, and I can't do that without rewinding the video. You've serialised a manifold isomorphic to R^3!  I have a problem with the bit right at the beginning though. It's not clear to me what is S^2 and what is Q. Clearly the points q_1 and q_2 are on S^2, and q then seems to be path of points on S^2 and t_1 and t_2 are on the real line? So the path function q picks out for each t in the interval [t_1,t_2] a single point in the general configuration space Q. So what we are trying to ascertain is whether there is some sort of canonical representation of the dynamics of the system that fixes the trajectories it can take through ...