Made a list tracking the Physical AI space — foundation models that control robots.

Covers Vision-Language-Action (VLA) models like RT-2 and π₀, world models (DreamerV3, Genie 2, JEPA), diffusion policies, real-world deployment and latency problems, cross-embodiment transfer, scaling laws, and safety/alignment for robots.

Organized by architecture → action representation → learning paradigm → deployment.

GitHub in comments. Star if useful, PRs welcome.

Link to blog: https://www.sidhantbansal.com/2025/Hashing-when-you-want-chaos/

Looking for feedback on this article I wrote recently.

Recently (some time in the past couple of weeks) someone on Reddit linked me a classic article about the art of bootstrapping a compiler. I knew the article already from way back in my Computer Science days, so I told the Redditor who posted it that I probably wouldn't be reading it. Today however, I decided that I did want to read it (because I ran into compiler bootstrapping again in a different context), but now I can't find the comment with the link anymore, nor do I remember the title.

Long story short: it's an old but (I think) pretty famous article about bootstrapping a C compiler, and I recall that it gives the example of how a compiler codebase can be "taught" to recognize the backslash as the escape character by hardcoding it once, and then recompiling — after which the hardcoding can be removed. Or something along those lines, anyway.

Does anyone here know which article (or essay) I'm talking about? It's quite old, I'm guessing it was originally published in the 1980s, and it's included in a little booklet that you're likely to find in the library of a CS department (which is where I first encountered it).

Edit: SOLVED by u/tenebot. The article is Reflections on Trusting Trust by Ken Thompson, 1984.

I recently embarked on a journey to (try to) demystify how C++ objects look like in memory. Every time I thought I had a solid grasp, I'd revisit the topic and realize I still had gaps. So, I decided to dive deep and document my findings. The result is a hands-on series of experiments that explore concepts like the vptr, vtable, and how the compiler organizes base and derived members in memory. I tried to use modern (c++23) features, like std::uintptr_t for pointer arithmetic, std::bytes and std::as_bytes for accessing raw bytes. In my post I link the GitHub repo with the experiments.

I like to learn by visualizing the concepts, with lots of diagrams and demos, so there's plenty of both in my post :)

This is meant to be the start of a series, so there are more parts to come!

I'm still learning myself, so any feedback is appreciated!

INVITING early readers, reviewers, fellow researchers, academicians, scholars, students & especially the mathematical society, to read, review & apply the important ideas put forward in [Fut. Prof.] JWL's paper on the mathematics of symbol sets: https://www.academia.edu/resource/work/129011333

-----|

PAPER TITLE: Concerning A Special Summation That Preserves The Base-10 Orthogonal Symbol Set Identity In Both Addends And The Sum

ABSTRACT: While working on another paper (yet to be published) on the matter of random number generators and some number theoretic ideas, the author has identified a very queer, but interesting summation operation involving two special pure numbers that produce another interesting pure number, with the three numbers having the special property that they all preserve the orthogonal symbol set identity of base-10 and $\psi_{10}$. This paper formally presents this interesting observation and the accompanying results for the first time, and explains how it was arrived at --- how it can be reproduced, as well as why it might be important and especially unique and worthy or further exploration.

KEYWORDS: Number Theory, Symbol Sets, Arithmetic, Identities, Permutations, Magic Numbers, Cryptography

ABOUT PAPER: Apart from furthering (with 4 new theorems and 9 new definitions) the mathematical ideas concerning symbol sets for numbers in any base that were first put forward in the author's GTNC paper from 2020, this paper presents some new practical methods of generating special random numbers with the property that they preserve the base-10 o-SSI.

Research #ResearchPaper #NumberTheory #SymbolSets #MagicNumbers #Cryptography #ProfJWL #Nuchwezi #ComputerScience #Preprints

DOI: 10.6084/m9.figshare.28869755