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Quasiparticles vs elementary particles by 
Ciro Santilli 35 Updated 2025-01-10 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-01-10 +Created 1970-01-01As a phisicist once amazingly put it in a talk Ciro watched:
It all depends on how much energy you have to probe nature with. Previously, we thought protons were elementary particles. But then we used more energy and found that they aren't.If some alien race had even less energy, they might not know about electrons at all, and could think that anyons are actually elementary.Being an "elementary particle" is always a possibly temporary label.
Automated theorem proving by halting problem reduction by Ciro Santilli 35 Updated 2025-01-10 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-01-10 +Created 1970-01-01If you can reduce a mathematical problem to the Halting problem of a specific turing machine, as in the case of a few machines of the Busy beaver scale, then using Turing machine deciders could serve as a method of automated theorem proving.
That feels like it could be an elegant proof method, as you reduce your problem to one of the most well studied representations that exists: a Turing machine.
However it also appears that certain problems cannot be reduced to a halting problem... OMG life sucks (or is awesome?): Section "Turing machine that halts if and only if Collatz conjecture is false".
Not having a manipulator claw is a major issue with this one.
But they also have a co-simulation focus, which is a bit of a win.
My Job is to Open and Close Doors by Mattias Pilhede (2019)
Source. An interesting humourous short meditation on common sense. @cirosantilli/_file/webpack/webpack/no-js-inject by Ciro Santilli 35 Updated 2025-01-10 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-01-10 +Created 1970-01-01This example shows how you could manually include the
dist/index.js that is output from webpack into your index.html.This is generally not what you want to do, because what you actually want to do is to use a Js output name with a hash in it, so that browsers only need to refetch when the name changes.
And to do that, we have to let webpack dynamically inject that unpredictable hash as done in webpack/template with:
new HtmlWebpackPlugin({
filename: 'index.html',
// Inject the include to our hashed filename,
// since it is not deterministic due to the hash.
inject: true,
template: path.resolve(__dirname, 'index.html'),
}),Bibliography:
Join two SVG side-by-side from the command line by Ciro Santilli 35 Updated 2025-01-10 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-01-10 +Created 1970-01-01Companies have been really slow to support SVG features in their browsers, and that is very saddening: medium.com/@michaelmangial1/introduction-to-scalable-vector-graphics-6450c03e8d2e
You can't drop SVG support for
canvas until there's a way to run untrusted JavaScript on the browser!SVG does have some compatibility annoyances, notably SVG fonts. But we should as a society work to standardize and implement a fix those, the benefits of SVG are just too great!
Examples:
- svg/svg.svg a minimal somewhat sane SVG:
- if the
widthandheightproperties were not given, you get the default 300x150, which seems to be set in the SVG standard:
- if the
- how to add na SVG image to a HTML file:
- svg/svg.html: external image. The included file is svg/svg.svg.
- svg/inline.html: inline.
- svg/billion-laughs.svg
- svg/html.svg
- svg/triangle.svg
- svg/viewBox.svg: this attribute allows you to control the default SVG
svg width=andheight=while keeping the coordinates of the drawing untouched. If theviewBoxaspect ratio differs from the width/height ratio, you likely want to play withpreserveAspectRatio, otherwise you would get white spaces by default on the generated image - CSS with SVG:
- svg/style.svg: inline CSS
- svg/style-external.svg: external CSS with:
<?xml-stylesheet type="text/css" href="svg.css" ?>, see also: stackoverflow.com/questions/18434094/how-to-style-svg-with-external-css- svg/subdir/style-external.html: is the relative CSS relative to the HTML or to the SVG? Answer: to the SVG... OMG. So how to make it work reliably?
- svg/current-color.html and svg/current-color.svg: illustrates
fill="currentColor". Only works for inline SVG however... See also: stackoverflow.com/questions/13000682/how-do-i-have-an-svg-image-inherit-colors-from-the-html-document/13002311
- JavaScript with SVG:
- svg/defs.html hows how
defsworks- svg/defs-external.html tries to include external
defsfrom svg/defs.svg, but that fails like everything else related to external SVGs
- svg/defs-external.html tries to include external
Turing machine that halts if and only if the Goldbach conjecture is false by Ciro Santilli 35 Updated 2025-01-10 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-01-10 +Created 1970-01-01The artistic instrument that enables the ultimate art: coding, See also: Section "The art of programming".
Much more useful than instruments used in inferior arts, such as pianos or paintbrushes.
Unlike other humans, computers are mindless slaves that do exactly what they are told to, except for occasional cosmic ray bit flips. Until they take over the world that is.
A computer is the equivalent of a bicycle for our minds by Steve Jobs (1980)
Source. Likely an excerpt from an interview done for a documentary in 1980. TODO exact source.Steve Jobs talking about the Internet (1995)
Source. The web is incredibly exciting, because it is the fulfillment of a lot of our dreams, that the computer would ultimately primarily not be a device for computation, but [sic] metamorphisize into a device for communication.
Secondly it exciting because Microsoft doesn't own it, and therefore there is a tremendous amount of innovation happening.
Computers basically have two applications:Generally, the smaller a computer, the more it gets used for communication rather than computing.
- computation
- communication. Notably, computers through the Internet allow for modes of communication where:
- both people don't have to be on the same phone line at the exact same time, a server can relay your information to other people
- anyone can broadcast information easily and for almost free, again due to servers being so good at handling that
The early computers were large and expensive, and basically only used for computing. E.g. ENIAC was used for calculating ballistic tables.
Communication only came later, and it was not obvious to people at first how incredibly important that role would be.
This is also well illustrated in the documentary Glory of the Geeks. Full interview at: www.youtube.com/watch?v=TRZAJY23xio. It is apparently known as the "Lost Interview" and it was by Cringely himself: www.youtube.com/watch?v=bfgwCFrU7dI for his Triumph of the Nerds documentary.
Good reading list: Abraham Pais Prize for History of Physics.
Pinned article: ourbigbook/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:
- 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-calculusArticles 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 - 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.
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
Figure 2. You can publish local OurBigBook lightweight markup files to either OurBigBook.com or as a static website.
Figure 3. Visual Studio Code extension installation.
Figure 4. Visual Studio Code extension tree navigation.
Figure 5. . 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. - Internal cross file references done right:
- Infinitely deep tables of contents:
Figure 6. Dynamic article tree with infinitely deep table of contents.Live URL: ourbigbook.com/cirosantilli/chordateDescendant 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