Atomic clock by Ciro Santilli 37 Updated 2025-07-16
Video 1.
How an atomic clock works, and its use in the global positioning system (GPS) by EngineerGuy (2012)
Source. Shows how conceptually an atomic clock is based on a feedback loop of two hyperfine structure states of caesium atoms (non-radioactive caesium-133 as clarified by the Wikipedia page). Like a quartz clock, it also relies on the piezoelectricity of quartz, but unlike the quartz clock, the quartz is not shaped like a tuning fork, and has a much larger resonating frequency of about 7 MHz. The feedback is completed by producing photons that resonate at the right frequency to excite the caesium.
Video 2.
Inside the HP 5061A Cesium Clock by CuriousMarc (2020)
Source.
A similar model was used in the Hafele-Keating experiment to test special relativity on two planes flying in opposite directions. Miniaturization was key.
Contains a disposable tube with 6g of Caesium. You boil it, so when it runs out, you change the tube, 40k USD. Their tube is made by Agilent Technologies, so a replacement since that opened in 1999, and the original machine is from the 60s.
Detection is done with an electron multiplier.
youtu.be/eOti3kKWX-c?t=1166 They compare it with their 100 dollar GPS disciplined oscillator, since GPS satellites have atomic clocks in them.
Video 3.
Quick presentation of the atomic clock at the National Physical Laboratory (2010)
Source. Their super accurate setup first does laser cooling on the caesium atoms.
Ubuntu feature request by Ciro Santilli 37 Updated 2025-07-16
Sometimes it just feels like Ubuntu devs don't actually use Ubuntu as a desktop.
Some extremely annoying problems are introduced and just never get fixed, even though they feel so obvious!
Would never happen on Mac...
JAR, SWF and CGI-bin scanning by path only is fine, since there are relatively few of those. But .js scanning by path only is too broad.
One option would be to filter out by size, an information that is contained on the CDX. Let's check typical ones:
grep -f <(jq -r '.[]|select(select(.comms)|.comms|test("\\.js"))|.host' ../media/cia-2010-covert-communication-websites/hits.json) out | out.jshits.cdx
sort -n -k7 out.jshits.cdx
Ignoring some obvious unrelated non-comms files visually we get a range of about 2732 to 3632:
net,hollywoodscreen)/current.js 20110106082232 http://hollywoodscreen.net/current.js text/javascript 200 XY5NHVW7UMFS3WSKPXLOQ5DJA34POXMV 2732
com,amishkanews)/amishkanewss.js 20110208032713 http://amishkanews.com/amishkanewss.js text/javascript 200 S5ZWJ53JFSLUSJVXBBA3NBJXNYLNCI4E 3632
This ignores the obviously atypical JavaScript with SHAs from iranfootballsource, and the particularly small old menu.js from cutabovenews.com, which we embed into ../cia-2010-covert-communication-websites/cdx-post-js.sh.
The size helps a bit, but it's not insanely good unfortunately, only about 3x, these are some common JS sizes right there!
Legal issues stalled them at the turning point of the Internet, and Linux won. Can't change history.
Did Apple just fork it and made Mac OS X without giving anything back?
TempleOS by Ciro Santilli 37 Updated 2025-07-16
The OS that the Gods ordered be made.
One is reminded of Ulillillia, see also: www.youtube.com/watch?v=9-79yOZ13qg The Story of Ulillillia by Atrocity Guide (2019)
Video 1.
I like elephants and God likes elephants
. Source.
Terry A. Davis by Ciro Santilli 37 Updated 2025-07-16
Video 1.
Terry A. Davis writes a message to the CIA
. Source.

Pinned article: Introduction to the OurBigBook Project

Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
We have two killer features:
  1. topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculus
    Articles of different users are sorted by upvote within each article page. This feature is a bit like:
    • a Wikipedia where each user can have their own version of each article
    • a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
    This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
    Figure 1.
    Screenshot of the "Derivative" topic page
    . View it live at: ourbigbook.com/go/topic/derivative
  2. local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:
    This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
    Figure 2.
    You can publish local OurBigBook lightweight markup files to either https://OurBigBook.com or as a static website
    .
    Figure 3.
    Visual Studio Code extension installation
    .
    Figure 4.
    Visual Studio Code extension tree navigation
    .
    Figure 5.
    Web editor
    . You can also edit articles on the Web editor without installing anything locally.
    Video 3.
    Edit locally and publish demo
    . Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.
    Video 4.
    OurBigBook Visual Studio Code extension editing and navigation demo
    . Source.
  3. https://raw.githubusercontent.com/ourbigbook/ourbigbook-media/master/feature/x/hilbert-space-arrow.png
  4. Infinitely deep tables of contents:
    Figure 6.
    Dynamic article tree with infinitely deep table of contents
    .
    Descendant pages can also show up as toplevel e.g.: ourbigbook.com/cirosantilli/chordate-subclade
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact