**Contents**

*science*

- More Busy Beaver Results

*tech*

- Notcurses
- Raspberry Pi Powered SMS Gateway
- DFeed - An RSS reader without login
- Some C64 Art from compos

*art*

- #OneWeek100People by Marc T. Holmes

# More Busy Beaver Results

I read a blog post about a result I was aware of relating to the busy beaver problem. The result is the following: it is impossible to prove the value of **BB(k)** in ZFC when **k = 7918**. ZFC stands for Zermelo–Fraenkel set theory with the axiom of choice. ZFC is basically “an axiomatic system that was proposed in the early twentieth century in order to formulate a theory of sets”. To sum up very generally a set of axioms from which all (?) mathematic theorems can be proven from.

Reading this blog post and trying to understand its impact sent me on a wild ride of reading other interestings bits I want to collect here so I can re-read / finish later. Here they are:

- The 8000th Busy Beaver number eludes ZF set theory: new paper by Adam Yedidia and me - The blog post summing up the results in the paper.
- A Relatively Small Turing Machine Whose Behaviour is Independent of Set Theory (PDF) - The PDF paper.
- The arXiv.org entry
- The Parsimony Language GH repository - This is the GH repo with a programming language that can be used create Turing machines compiled from source code
- Turing Machine Tutorial - YT tutorial on how to use parsimony to build a Turing machine that wants to check if
**x² < 5 for all x**. - Zermelo–Fraenkel set theory - Wiki page explaing
**ZF**and in particular**ZFC**. - Book Review: ‘A New Kind of Science’ - A review of Wolframs ‘A New Kind of Science’ book. Aaronson is very critical of NKS and this is an interesting review of Wolframs book with interesting comments. ⌛
- Wolfram’s 2-state 3-symbol Turing machine - I wasn’t aware of this result: aparently there is a very simple 2-state, 3 symbol Universal Turing machine. Although its very hard to write programs for such a machine it’s interesting to be able to prove it is universal. There is a big caveat in this result: aparently you need to not only allow infinite periodic initial state for the tape but also certain non-periodic initial configurations Universal Turing Machine. I need to read more about this.
- The Busy Beaver Frontier - A survey of the Busy Beaver survey paper “In this survey, I offer a personal view of the BB function 58 years after its introduction, emphasizing lesser-known insights, recent progress, and especially favorite open problems” ⌛
- Beeping Busy Beavers -
- An Automated Approach to the Collatz Conjecture - A relatively new paper relating to the Collatz Conjecture I would like to read. From the paper: “Although we do not succeed in proving the Collatz conjecture, we believe that the ideas here represent an interesting new approach.” ⌛
- Something Something Programming - A cool blog with a couple of intereting looking articles on the Busy Beaver question. ⌛
- Quantum Computational Supremacy - A talk by Scott Aaronson explaining “Quantum Computation Supremacy” given on September 9, 2021.

# Raspberry Pi Powered SMS Gateway

How to build a Rasperry Pi powered SMS gateway with a simple PHP based API. This is the article and the GH repo here

# DFeed - An RSS reader without login

Show HN: Dfeed – a feed reader you can use without an account https://dfeed.net

# Notcurses

A library facilitating complex TUIs on modern terminal emulators, supporting vivid colors, multimedia, threads, and Unicode to the maximum degree possible. Things can be done with Notcurses that simply can’t be done with NCURSES. It is furthermore fast as shit.

# Some C64 Art from compos

There were a couple of demo compos lately and here are some C64 graphics and PETSCII entries which I liked.

St. Basil by Hammerfist / Desire - Released at Syntax 21

Time out by Feailrlight - released at Transmissing64 2021 Fall Edition

Bebes by Extended - released at Transmissing64 2021 Fall Edition

Hyperspace by Dr.TerrorZ PETSCII - Released at Syntax 21

# #OneWeek100People by Marc T. Holmes

An urban sketcher I really like is **Mark Taro Holmes**. I love his simple approach to skeching and the fresh results he gets with a simple 3 step technique that he develops in his Travel Sketching in Mixed Media Craftsy course. I re-discovered his blog lately and wanted to show case some of his work. Every year he hosts a challenge to draw 100 people in 5 days. The artwork I show below are from previous challenges. You can read more about the challenge in this blog post