18,923 karma · joined September 29, 2009
Your perspective guides your thoughts, your choices, your trajectory.
All problems boil down to one thing: Lack of truth.
Truth is optimal. A super-optimizing AI would optimize the process of connecting what's true.
Current Focus: Knowledge Systems and the physics underpinning the structure of information.
Ptrs, social knowledge
» https://ptrs.app
Whybase, social reasoning
» https://whybase.org
Bulbs, Python persistence framework for graph databases
» https://github.com/espeed/bulbs
Apache TinkerPop, open-source graph developers group
» https://tinkerpop.apache.org
Pipem, natural-language commands
» Pitch Day 2015: https://www.youtube.com/watch?v=o_0DSmZhLGw
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https://espeed.dev/contact
(-> ⁎ u $ ! b ? W *p (~) △ |m| .~)
The most important question is "Why?"
[ my public key: https://keybase.io/espeed; my proof: https://keybase.io/espeed/sigs/YxmnIJ03yV6kqenrZXSh962j_dpxVHRhjLB8z8Acfpk ]
[1] https://www.forbes.com/places/tx/
[2] https://en.wikipedia.org/wiki/Comparison_between_U.S._states...
Map Map [pdf] http://www.mit.edu/~kepner/GravelMathMap.pdf
[1] Graph Algorithms in the Language of Linear Algebra, by Jeremy Kepner and John Gilbert https://epubs.siam.org/doi/book/10.1137/1.9780898719918
[2] IBM GraphBLAS https://github.com/IBM/ibmgraphblas
[3] Jenna Wise, CMU http://www.cs.cmu.edu/~jlwise/
[4] Formal verification proof of the GraphBLAS C API https://github.com/jennalwise/graphblas-verif
[1] RedisGraph 1.0 launch video https://www.youtube.com/watch?v=S5WWBzi0LcM
[2] RedisGraph 1.0 https://github.com/RedisLabsModules/RedisGraph
[3] RedisGraph benchmarks https://redislabs.com/redis-enterprise/redis-modules/redis-e...
But MIT and Sandia Labs are taking the linear algebra model to the next level, and are now working on encoding an entire operating system in the language of linear algebra...
Jeremy Kepner (the head of MIT Lincoln Labs and GraphBLAS lead) and his team just published a paper [2] where they define an entire unix operating system using the same linear algebra model as they used for D4M/GraphBLAS. The linear-algebra OS model scales linearly way beyond the Linux limits, and since the entire OS kernel representation is defined as generic matrix transformations, it can run on any processor, including CPUs, GPUs, or a cluster of TPUs.
[1] A Linear Algebraic Approach to Datalog Evaluation (2017) [pdf] https://arxiv.org/abs/1608.00139
[2] TabulaROSA: Tabular Operating System Architecture for Massively Parallel Heterogeneous Compute Engines (2018) [pdf] https://arxiv.org/pdf/1807.05308.pdf
See previous discussions on GraphBLAS https://hn.algolia.com/?query=GraphBLAS&sort=byPopularity&pr...
NB: GraphBLAS runs in the recently-released RedisGraph. The Datalog linear-algebra approach is so close to simi-ring primitives in GraphBLAS. A Datalog implementation on GraphBLAS could be slick as hell. The GraphBLAS code is implemented by Tim Davis, and the code is pristine.
[1] A Linear Algebraic Approach to Datalog Evaluation (2017) [pdf] https://arxiv.org/abs/1608.00139
[2] GraphBLAS http://faculty.cse.tamu.edu/davis/GraphBLAS.html Discussion: https://hn.algolia.com/?query=GraphBLAS&sort=byPopularity&pr...
[1] https://hn.algolia.com/?query=GraphBLAS&sort=byPopularity&pr...
And of course there's also the videos of lectures of the MIT 6.815/6.865 course on computational photography given by Frédo Durand (those videos are linked to from the Halide home page under the Getting Started section [3]).
[1] Stanford CVPR2015 http://halide-lang.org/cvpr2015.html
[2] Decoupling Algorithms from the Organization of Computation for High-Performance Graphics & Imaging (MSR talk given by Jonathan Kelley) [video] https://www.youtube.com/watch?v=dnFccCGvT90
[3] MIT 6.815/6.865 Digital & Computational Photography lecture videos by Frédo Durand http://halide-lang.org/#gettingstarted
[1] https://news.ycombinator.com/user?id=pron
[2] https://pron.github.io, http://www.paralleluniverse.co
[3] https://twitter.com/pressron, https://twitter.com/puniverseco
Halide: a language for fast, portable computation on images and tensors http://halide-lang.org/
An Alternative to Arithmetic Coding with Local Decodability (2010) [pdf] http://people.csail.mit.edu/mip/papers/trits/paper.pdf
Changing base without losing space (2010) [pdf] https://dl.acm.org/citation.cfm?id=1806771 (same paper as above, different title)
"The ternary numeral system (also called base 3) has three as its base...a ternary digit (trit) is analogous to a bit. One trit is equivalent to log2 3 (about 1.58496) bits of information" [1].
NB: Base 3 is the integer base with the lowest average radix economy; however, base e has the lowest average radix economy overall [2].
[1] Ternary numeral system https://en.wikipedia.org/wiki/Ternary_numeral_system
[2] Radix economy https://en.wikipedia.org/wiki/Radix_economy
[3] Three-valued logic https://en.wikipedia.org/wiki/Three-valued_logic
Another good one is MathTheBeautiful [1] by MIT alum Pavel Grinfeld [2]. He approaches Linear Algebra from a geometric perspective as well, but with more emphasis on the mechanics of solving equations. He has a ton of videos organized into several courses, ranging from in-depth Intro to Linear Algebra courses to more advanced courses on PDEs and Tensor Calculus.
Esp note his video on Legendre polynomials [3] and Why {1,x,x²} Is a Terrible Basis: https://www.youtube.com/watch?v=pYoGYQOXqTk&index=14&list=PL....
Gilbert Strang was Greenfield's PhD advisor: https://dspace.mit.edu/handle/1721.1/29345. Pavel has a clear and precise teaching style like Strang, and he makes reference to Prof's Strang and his MIT course from time to time.
NB: Prof Strang has a new book Linear Algebra and Learning from Data that just went to press and will be available in print by mid Jan 2019. A few chapters are available online now, and the video lectures from the new MIT course should on YouTube in a few weeks. [4]
[0] Essence of Linear Video Series (3Blue1Brown): https://www.youtube.com/channel/UCYO_jab_esuFRV4b17AJtAw/pla...
[1] MathTheBeautiful https://www.youtube.com/watch?v=pYoGYQOXqTk&index=14&list=PL
[2] https://en.wikipedia.org/wiki/Pavel_Grinfeld
[3] https://en.wikipedia.org/wiki/Legendre_polynomials
[4] MIT Linear Algebra and Learning from Data (2018) http://math.mit.edu/~gs/learningfromdata/
Also, the 2017 Clojure/West talk "Synthesis and Verification for All" [1] presented by UW Prof Emina Torlak (Rosette's creator) is one of the best talks I've seen in a while.
Synthesis and Verification for All, Emina Torlak [video] https://www.youtube.com/watch?v=KpDyuMIb_E0
[1] https://en.wikipedia.org/wiki/J-invariant
[2] https://en.wikipedia.org/wiki/Steiner_system
[3] https://en.wikipedia.org/wiki/Binary_Golay_code
[4] https://en.wikipedia.org/wiki/Mathieu_group_M24
[5] https://en.wikipedia.org/wiki/Leech_lattice
[6] https://en.wikipedia.org/wiki/Monster_group
[7] https://en.wikipedia.org/wiki/Monstrous_moonshine
Does anyone here know of any theorems that relate the curve of a cycloid [1] to the curve of the horopter [2] (in particular, the empirical horopter)?
In my continued quest to connect curious properties of the cycloid, I noticed hints of potential correspondences between the two curves beyond just their shape, particularly in the ways the curves of the cycloid and horopter both relate to the path of light.
A few years back, Grant did a 3Blue1Brown video with with Steven Strogatz on the cycloid Brachistochrone curve : https://www.youtube.com/watch?v=Cld0p3a43fU
And Vsauce did one with Adam Savage on the Brachistochrone [3] where they build a mechanical model of one that shows it's the fastest/optimal path among different curves, and their experiment also shows the cycloid Tautochrone [4] invariant property where objects begin up the curve at different distances apart and yet all arrive together simultaneously in constant time. https://www.youtube.com/watch?v=skvnj67YGmw
Some other interesting properties and places the cycloid shows up...
* The arclength of the cycloid curve is 8R, a rational value given a rational radius.
* The shape of the closed universe [5]. While we don't yet know if the shape of the universe is open or closed, we do know that if the universe is closed the shape of its evolution is precisely the shape of a cycloid.
* Spinors [6], octonions, and the epicycloid [7]. Electrons, protons, neutrinos, and quarks are spinors. The Rolling Spinor is like a ball, but "thanks to the 'double' in the double cover SU(2)→SO(3), a 360∘ rotation does not act like the identity. Instead, we need to rotate by 720∘ degrees to get back where we started" [8]. The two balls have a 3-to-1 ratio, and the path traced out around the larger ball is an epicycloid.
[1] Cycloid https://en.wikipedia.org/wiki/Cycloid
[2] Horopter https://en.wikipedia.org/wiki/Horopter , Hering–Hillebrand deviationn https://en.wikipedia.org/wiki/Hering-Hillebrand_deviation
[3] Brachistochrone curve https://en.wikipedia.org/wiki/Brachistochrone_curve
[4] Tautochrone curve https://en.wikipedia.org/wiki/Tautochrone_curve
[5] MIT 8.286 The Early Universe: Introduction to Non-Euclidean Space [video] https://www.youtube.com/watch?v=YfbXB_MSkSY
[6] Spinor https://en.wikipedia.org/wiki/Spinor
[7] Epicycloid https://en.wikipedia.org/wiki/Epicycloid
[8] G2 and the Rolling Ball https://golem.ph.utexas.edu/category/2013/06/g2_and_the_roll...
Split Octonions and the Rolling Ball, Dr. John Baez [video] https://www.youtube.com/watch?v=xvflQcHT5C4
Eric Weinstein explains Gauge Symmetry [video] https://www.youtube.com/watch?v=2xiEEtoa-_4