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taliesinb

2,464 karma · joined July 25, 2010

Category theory and AI @ symbolica.ai

https://tali.link

https://twitter.com/taliesinb

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taliesinb··on Demystifying the second law of thermodynamics
Frustrating, that list contains almost no usable links. Its as if he doesn’t want you to actually read or understand what he is saying.
taliesinb··on Superoptimizer – A Look at the Smallest Program [pdf] (1987)
Brute force search of the computational universe of simple programs for useful ones – that rings a bell, but I can’t think where I have seen that before!
taliesinb··on The Flat Tax Increases Growth
Maybe we need to think about whether modern capitalist economies are higher-order lifeforms that have produced many systems, including systems of economic rationalization and "consent manufacture", that directly optimize their... ecomass. It's no longer really about class and the means of production -- we're seeing how an organism that is larger than us has learned how to reprogram us to better serve its need. The paper clip optimizer is already here, folks!
taliesinb··on Demystifying the second law of thermodynamics
It’s probably been 15 years since I looked in detail at a formal treatment of statistical mechanics, so maybe this is well-trodden territory, but... has anyone formalized the idea that the second law can be interpreted as a general inability of computer programs to predict one another? I’m also channeling Wolfram here, but I’m not sure if he ever expressed it exactly this way. But the thing I’m imagining would be: set up some (preferably discrete) dynamical system, and then another different kind of system that you fit variationally to the first. The claim would be that the mutual information between state variables of the second and the first will always gradually decrease — unless they are the exactly the same family, in which case the fit rediscovers the exact dynamics and the two systems are identical. So intuitively, the second law would correspond to the claim that different families of programs cannot accurately simulate each other for very long. In the special case of a coarse graining, this should give you the more familiar story about entropy and the ‘gap’ between macrostates and microstates, but the real story is a more general one than that and is an empirical fact about the “computational universe”, with physics a special case.
taliesinb··on The Censored: Ford Fischer
I can recommend Taibbi’s writing on substack. Funny, and refreshingly cynical in an age when most liberal journalists seem to have decided that the dangers of Trumpism demanded absolute obsequence to the other side.
taliesinb··on BetterExplained: Clear, intuitive lessons about mathematics
Second this. I’m working on a set of ideas about how best to enable arbitrary learning trajectories through a knowledge graph — partly in an effort to better capture my own learning in mathematical topics. I liked how Quantum Country integrated spaced repetition into its presentation of quantum computing, but I think you could go further and structure all knowledge you wish to communicate in a graph form. There are so many reasons to do this: it’s a graph in your head anyway, and if a machine can track and manage that graph it can better help you navigate it in a learning-optimal way. Just try reading some math on wikipedia and you’ll see where this could really shine. Currently it’s a frustrating experience because there are many slices of information that you might benefit from when you are looking up eg the article on distributive lattices, but the optimal slice to see depends on what examples you’ve encountered, what other topics are fresh in your mind, and what your short term goals are. Of course a textbook is a particular curated walk through this graph, but people are different, and there is no walk that is optimal for all people. A dedicated expert teacher can curate a path specifically for a learner, but almost no one can afford to employ such a teacher for them. If machines can handle the UX aspects of this graph-walking and graph-building for us (there are many simple ideas that fit into this), I believe we could have a real step change in learning efficiency with only modest investments in building such graphs. And the truth is, such graphs are actually fun to build because they are so interactive! It’s very similar to the semantic web, but catering specificity to humans and their idiosyncratic educational needs rather than to more nebulous things about machine reasoning or scripting.
taliesinb··on Algorithms for Causal Reasoning in Probability Trees
A very nice paper.

I'm quite happy to see more work on discrete generative models -- probabilistic programming languages are still wrestling (or simply ignoring!) the problem of "disintegration", where conditioning changes the base measure because it collapses the dimensionality of the probability manifold (similar to the issue Arjovsky identified with GANs). See e.g. http://homes.sice.indiana.edu/ccshan/rational/disint2arg.pdf and https://probprog.cc/assets/posters/thu/78.pdf. To me (although this is probably too radical a move to be palatable to most people) we should largely abandon continuous distributions and start building out discrete probability spaces and methods with the same vigor that continuous probability got in the form of measure theory. These probability trees some like a natural data structure to begin this. I'd also like to see representations for working with probabilities on discrete manifolds that approximate continuous space in computationally efficient ways -- there could be work in this direction already but I'm not aware of it.

Also, a fun implication of these probability trees I'd like to see explored is structural sharing: you need not copy an entire tree to represent the result of a conditioning or intervention. In general you need to copy only a number of nodes given by the size lying above the cut set, in a similar way to how immutable data structures like HAMTs can represent modified hash maps etc with persistent space efficiency by reusing unchanged nodes. If one expects to condition often with certain variables, it would then be useful to hoist such cut sets as high as possible -- does such a 'transpose' operation exist? I admit I did not read the paper thoroughly enough to know if this was mentioned.

taliesinb··on Governments Worldwide Consider Ditching Daylight Saving Time
That’s straight out of Tintin and the Broken Ear, where a would-be terrorist blows himself up after a time change: https://imgur.com/gallery/27jxctY
taliesinb··on The Black Hole Information Paradox Comes to an End
Heartening to see that unusual perspectives and opinions are rewarded with downvotes.
taliesinb··on The Black Hole Information Paradox Comes to an End
Because I don’t think infinite amounts of information, and uncomputable numbers, exist. They are fantasies, and relatively recent ones at that. Unfortunately those fantasies came to dominate 20th century mathematics, and in the guise of string theory obtained a death grip on fundamental physics. Fortunately a new generation of smart people, with intuitions honed on computers, is well placed to capitalize on this arbitrage opportunity.
taliesinb··on The Black Hole Information Paradox Comes to an End
To someone like me, who believes that the universe is, must be, fundamentally a computer, the actual academic paper is hardly any better. Whatever the paper is doing is not describing any kind of computational process. It's a mille-feuille of semi-rigorous mathematical abstraction that sounds far more like a kind of liturgical incantation than a description of the software our universe is running.

That's not to say it is definitely not useful! It could be that, for some bizarre reason, reading the mathematical tea leaves of our current incomplete (and incoherent) theories might well yield insight into post-quantum physics. I do doubt it though.

taliesinb··on Homotopy Type Theory (2012) [pdf]
Couldn’t agree more.

A great example of a mathematics popularizer along these lines is Norman Wildberger, who has an astonishing range of videos on youtube about an amazing range of mathematical topics. Here’s an interview with him: https://youtu.be/E_dGqavx5AU .

My personal feeling is that a lot of beautiful and interesting mathematics will arise as a result of an intuitionist, finitist, computationalist rethinking of the foundations of mathematics.

taliesinb··on Gravity is not a force – free-fall parabolas are straight lines in spacetime
A fun little physical experiment: a density gradient of the water in a fish tank (caused say by putting sugar in the water) will cause a laser to bend: https://www.youtube.com/watch?v=DhNZP2KgMLw

How this can be connected to gravity I do not exactly know. I suppose the change in the refractive index of the water is akin to g_{00} component of the Riemann metric, since it produces a compensating change in the wave vector at that point. Whether you could imagine GR consistently in terms of changes in the local speed of light a.k.a. changes in the permittivity of free space, again, I do not know.

taliesinb··on Lambda Calculus Diagrams (2015)
Kauffman’s book looks like a treasure trove! Reminds me of Penrosee’s RTR. Thanks for linking.
taliesinb··on Obverse and Under (2019)
J seems like this alien bit of technology that is powerful but inscrutable. It also doesn’t seem to have any nice introductions / videos on YouTube. Anyone have some pointers handy for someone who wants to get the “big ideas” of J with a minimum of time investment?
taliesinb··on Topology from the Perspective of Category Theory
Thanks! By nlab book you mean the whole nlab project? Also, can you help me understand the connection to lattices? Do they model intersection and union of open sets? Why is finiteness needed for lattices to be appropriate?
taliesinb··on Topology from the Perspective of Category Theory
Can anyone recommend a finitist, constructivist approach to topology? I’m really most interested in discrete geometry, but a geometry that doesn’t try to preserve traditional concepts like curvature, angle, volume etc, but builds them up from scratch from finite graphs. A discrete-first approach, like how Lattice Boltzmann methods are approximated by Navier Stokes rather the way FEM solvers discretize Navier Stokes.
taliesinb··on The Recursive Universe
Disclosure: I worked on Mathematica for ~8 years.

I think the value of Stephen's big book is that served as a kind of manifesto to "take computation seriously". By that I mean: to think about computations, in the abstract, as a kind of new mathematics about which we know almost nothing, and about which our naive intuitions from other domains is almost totally inapplicable. It is an injunction to explore the "computational universe", in other words, the "universe of simple computational systems", where CAs live as one of several kinds of maximally simple form of computation (which Wolfram made some attempt to categorize and explore).

By analogy, think about the development of algebra. It didn't come naturally! Yet Algebra is one of the most natural ideas in abstract mathematics, incredibly simple and incredibly powerful, lying as a rosetta stone connecting so many other topics in mathematics. But people didn't immediately accept or describe it; it took many hundreds of years to crystalize and mature as a topic. It's a very old piece of the operating system of mathematics that underwent a lot of hacking and refactoring.

Wolfram proposes we think about computational systems in the same way, as a nascent field that needs exploration, mapping, the irrigation of young minds and new ideas. It may be some time before it yields a harvest. We shouldn't expect it to immediately revolutionize everything.

Even after Turing, computational systems existed as a kind of diaspora in mathematics, having sat unrecognized in all kinds of places, never having had a sort of independent state in which they are not considered as an aspect of something else, as somehow alien and unworthy of respect because of their confusing aspects. Largely, there were two reasons they were treated so shoddily:

1. they required computers (and good computer tools) to actually explore, since they produced complex and irreducible computations 2. they resisted any kind of analysis by prior mathematics

In other words, we were not ready to really probe them until a few decades ago, and even now our software is not well suited to explore them (Mathematica remains the best tool for the job, though I anticipate Julia will surpass it rapidly). Furthermore, traditional mathematical fields have not adapted to the presence of computation very gracefully.

I guess I would summarize: NKS is an imperfect book and Stephen an imperfect herald of the ideas within. But he was the first person to really articulate those ideas crisply and push them hard into the imagination, and I'm very glad he did. The hand he overplayed was the application to the natural world -- I think that will take longer to pay off than he predicted.

taliesinb··on The Recursive Universe
Cellular automata are like the `y = m * x + b` of the algorithmic universe.

Personally, I believe it is inevitable that a vast and rich new mathematical world will spring up around simple computational systems, where they are the primary object of study and not relegated to being games, "simulations" of something else, curiosities, etc. CAs are just the "hello world" of this universe.

In that future, your attitude will be seen as a kind of parochial holdout of 20th century attitudes.

The new mathematics will:

* privilege finite, discrete systems

* be explicitly constructivist

* not shy away from computational enumeration and classification

* be much more visual, but no less rigorous than our last few hundred years of mathematics

* make deep connections with many new technological systems, like Git, distributed systems, blockchains, computer networks, trust networks, social networks, etc.

* most importantly, be way more fun than old math!

It will exploit to the full the capabilities of computer systems to make the new systems tangible, so that the idea of a 'math paper' will be itself quite old fashioned -- most mathematical work will start with forking a Git repo or the equivalent, and most communication and education will be interactive interrogation of computational systems using a kind of souped-up, computation-focused REPL. It's the kind of mathematics that will be natural when Brett Victor's ideas are actually implemented.

Wolfram's NKS book is the prototype work of this kind, but it will also be seen as quite a product of its time and of the author's prior commitments to physics, math, etc. And of course distorted by the classic Wolfram immodesty.r

taliesinb··on Self-Classifying MNIST Digits Using Neural Cellular Automata
Hi there! Like this line of work. As an enthusiast of Alife-ish things, CAs (and NKS-style computational systems generally), and also an author of an ML library, I was looking forward to jumping on the slack and just having a chat with likeminded folk, but I'm having trouble finding how to actually make an account on https://distillpub.slack.com
taliesinb··on How Many Decimals of Pi Do We Need?
Maybe we should be using rational trigonometry instead: https://www.youtube.com/playlist?list=PL3C58498718451C47
taliesinb··on Computability in Linear Algebra (2004)
Interesting. Also, small world: One of the authors (Vasco) taught me computability at the University of Cape Town.

What I find quite interesting to think about is how the complexity (as a function of accuracy) of a “taken-for-granted” computational process works in the context of another process. For example, the eigensystem of its adjacency matrix provides powerful understanding of a graph — but how much accuracy do you need in order to trust that understanding? If you need arbitrary precision because of the pathological features of a particular family of graph (expander graphs, say), and the scaling of the needed precision links directly to aspects of that graph pathology, this is really telling you that the eigenvector computation is not the most natural “computation basis” to approach this phenomenon — and some explicitly discrete algorithm would make this latent complexity relationship manifest. Probably individual instances of this kind of phenomena are well known to those who study the relevant structures, but I’m not sure if the general phenomena is described or modeled anywhere.

In some weird sense you can link this to a kind of “computational curvature” — ala some of Wolfram’s metamathematical musings. If one’s prior is to distrust continuous mathematics and see only discrete computational processes as “real”, it’s exactly the kind of phenomena one will be on the lookout for. Anyway, the curvature analogy is that as you attempt to maintain a particular computational basis for computing a phenomena of interest as its complexity scales, other typically-uncorrelated complexity requirements that are normally treated as constants will explode. Needs to be made more concrete though.

taliesinb··on Kindergarten Quantum Mechanics
If you want to see the author riff on density matrices, check out this recent video: https://youtu.be/wP_Jsxn7BA4?t=1020

And by riff I mean with an actual electric guitar

taliesinb··on Reviving Patronage and Revolutionary Industrial Research
I couldn’t agree more with this article.

I happen to be working on a new way to look at quantum mechanics, based on finite combinatorial objects called multi-way systems, and after just a few weeks I’ve made a very satisfying amount of progress.

Maybe it won’t go anywhere. But if it succeeds, it should generate the abstract algebraic structure of QM — complex Hilbert spaces — from a more elegant, intuitive, general, and natural set of axioms. If it succeeds, it will probably be how we teach quantum mechanics in 50 years. And I’ll have to write the textbook! As a side bonus, it could also reveal quantum mechanical behavior in a much wider set of systems in the natural sciences, unconnected with physics.

Sure, saying all these things out aloud sounds super grandiose and silly. But I wouldn’t be doing this if I didn’t think it could work. Obviously it’s super risky, but that’s the only reason I’m actually interested in trying it — the high stakes are what get me up every day, obsessing about it, talking about it, reading endlessly, trying different permutations of ideas, etc.

Now, I’m self funded. I would struggle to imagine someone who would fund me to do this. Or an institution or adviser that would regard it as a suitable topic for a PhD. How on earth could something so ambitious possibly work? Who the hell do I think I am? etc.

But we need hundreds of people doing this — one of them will probably succeed, and it will change the world!

taliesinb··on Climb Mount Improbable: Evolvable Critters in JavaScript
At the bottom of the page I linked are some resources. But you can take a look at the most recent alife conferences like... ALife and GECCO to see what people are up to these days.
taliesinb··on Climb Mount Improbable: Evolvable Critters in JavaScript
Beautifully done!

Blind Watchmaker had a big impact on me as a kid. After I had read it, I programmed my own take on the biomorphs program and sent a copy of my program to Richard Dawkins. His research assistant Yan Wong replied with a very complimentary email. I wish I still had the email.

I've been playing with evolutionary algorithms ever since, such as https://taliesin.ai/projects/science/floatworld/

taliesinb··on Ask HN: What's your quarantine side project?
Thanks!
taliesinb··on Electron 9.0
Yup. I'm just shocked that https://github.com/microsoft/vscode/issues/76594#issuecommen... has been open for more than year now. Two finger scroll that lags for up to 1 second! Imagine the uproar if Apple introduced this bug into XCode and then ignored the ticket for an entire year.
taliesinb··on Port knocking
I implemented a physical port-knocking daemon, once. I lived in a block of flats — you needed an expensive fob to open the outer gate, and it didn’t even work reliably.

I lost my fob. So I took my intercom apart and wired a band pass filter circuit between the buzzer input and actuator output. If you pressed my buzzer with the right steady pattern, it would automatically let you in.

It worked great and I didn’t buy a replacement fob.

A few months later I started getting woken up by someone buzzing my buzzer. They would always scurry in before I could open my door to see who it was.

Turns out my upstairs neighbor saw my shenanigans a few times and started freeloading off my invention. Honestly amazed he/she reverse engineered what was going on!

Needless to say, I bought a new fob.

taliesinb··on Ask HN: What's your quarantine side project?
Nice. Also a Bear fan. I've actually tried your Graphviz code before! I just wish there was an opensource Zettelkasten-ish platform like Bear that I can customize to by extra nerdy preferences.
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