a.k.a. hakank. Swedish Software Developer (retired) / Independent Researcher. Interested in many things, e.g. Constraint Prog., OR, AI, ML, Picat, Prob. prog.
Joined May 2008
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- Followers 990
- Likes 1,883
41 Photos and videos
3 Dec 2025
I just completed "Lobby" - Day 3 - Advent of Code 2025 adventofcode.com/2025/day/3 #AdventOfCode
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Hakan Kjellerstrand retweeted
1 Dec 2025
Anyone interested in working on developing an efficient compiler for constraint programming? In Rust! We have an exciting project with a lot activity and several opportunities to contribute in many ways. Get in touch!
Funded PhD studentships: st-andrews.ac.uk/computer-sc…
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2 Dec 2025
I just completed "Gift Shop" - Day 2 - Advent of Code 2025 adventofcode.com/2025/day/2 #AdventOfCode
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Hakan Kjellerstrand retweeted
2 Dec 2025
🤔Can AI reveal hidden structure in the Standard Model?
A new paper by @svchekanov @hakankj in Particles proposes a research program using #AI to tackle the longstanding problem of many free parameters of the Standard Model.
Welcome to read and discuss
mdpi.com/2571-712X/8/4/95
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1 Dec 2025
Our (@svchekanov and me) #physics paper "Discovering the Underlying Analytic Structure Within Standard Model Constants Using Artificial Intelligence" has now been accepted and published in the Particles journal: mdpi.com/2571-712X/8/4/95
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1 Dec 2025
It proposes a research program using #AI to tackle the longstanding problem of many free parameters of Standard Model
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1 Dec 2025
I just completed "Secret Entrance" - Day 1 - Advent of Code 2025 adventofcode.com/2025/day/1 #AdventOfCode
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27 Nov 2025
Picat PPL (hakank.org/picat/ppl) - Probabilistic Programming Light is is a lightweight probabilistic programming framework implemented entirely in Picat (picat-lang.org/).
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27 Nov 2025
The dedicated page for Picat PPL is hakank.org/picat/ppl . And at GitHub: github.com/hakank/hakank/tre… .
Also, the published files can be downloaded from the Zip file: hakank.org/picat/ppl/all_pub… . This file will be updated when changes are done.
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27 Nov 2025
The Picat PPL page includes documentation of the features of Picat PPL as well as over 550 probabilistic programming models. (In total, it's now over 115 000 lines, including comments and output of the models.)
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29 Oct 2025
Just committed some #Picat programs: github.com/hakank/hakank/com…
It's mostly puzzles solved by my Symbolic Regression module (hakank.org/picat/#symbolic_r… )
(Just to clear the list in preparation for a fairly large update of a new #Picat toolkit models, expected to be released soon. )
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29 Oct 2025
Just committed some #Racket/#Gamble probabilistic programming programs: github.com/hakank/hakank/com…
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14 Sep 2025
Crespin, Kostis, Verhaeghe, Schaus: "CP-Model-Zoo: A Natural Language Query System for Constraint Programming Models": arxiv.org/pdf/2509.07867
The system is available here: cp-model-zoo.info.ucl.ac.be/
GitHub: github.com/crespina/LLM4CP
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14 Sep 2025
Here is Augustin Crespin's Master thesis: "CP-Model-Zoo - A Natural Language Query System for Constraint
Programming Models": thesis.dial.uclouvain.be/ent…
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13 Sep 2025
Hillel Wayne: "Many Hard Leetcode Problems are Easy Constraint Problems - Use the right tool for the job.": buttondown.com/hillelwayne/a…
Examples are shown in #MiniZinc (minizinc.org/).
And the mandatory discussion on Hacker News: news.ycombinator.com/item?id…
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Hakan Kjellerstrand retweeted
11 Sep 2025
The problem with many free parameters in the #StandardModel might finally be tackled with #AI (/symbolic regression)! A new paper co-authored with @hakankj illustrates this method: arxiv.org/abs/2509.07713
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10 Sep 2025
Our second physics paper (preprint) is now available at arXiv: S. V. Chekanov (@svchekanov), H. Kjellerstrand (@hakankj): "Evidence of Relationships Among Fundamental Constants of the Standard Model" (arxiv.org/abs/2509.07713)
Abstract: See next comment.
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10 Sep 2025
The found analytic solution depends on only two input parameters, representing the simplest mathematical model that could provide a foundation for developing a future theoretical framework to address the SM.
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10 Sep 2025
The found analytic solution depends on only two input parameters, representing the simplest mathematical model that could provide a foundation for developing a future theoretical framework to address the SM.
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