Plancherel theorem by Ciro Santilli 35 Updated +Created
Some sources say that this is just the part that says that the norm of a function is the same as the norm of its Fourier transform.
Others say that this theorem actually says that the Fourier transform is bijective.
The comment at math.stackexchange.com/questions/446870/bijectiveness-injectiveness-and-surjectiveness-of-fourier-transformation-define/1235725#1235725 may be of interest, it says that the bijection statement is an easy consequence from the norm one, thus the confusion.
Partial derivative symbol by Ciro Santilli 35 Updated +Created
Nope, it is not a Greek letter, notably it is not a lowercase delta. It is just some random made up symbol that looks like a letter D. Which is of course derived from delta, which is why it is all so damn confusing.
I think the symbol is usually just read as "D" as in "d f d x" for .
Computer YouTube channel by Ciro Santilli 35 Updated +Created
Publishing by Ciro Santilli 35 Updated +Created
Beta by Ciro Santilli 35 Updated +Created
Keyhole Inc. by Ciro Santilli 35 Updated +Created
Public school (united-kingdom) by Ciro Santilli 35 Updated +Created
They are not public in any meaningful modern sense, just like "public universities" in the United Kingdom: are public universities in the UK owned by the Government?.
Markua by Ciro Santilli 35 Updated +Created
In leanpub you write your book in a markdown variant they call Markua, marketed as "markdown for books".
TODO is there a reference implementation that runs locally for HTML output? Or the only reference implementation is closed under leanpub?
Flagellum by Ciro Santilli 35 Updated +Created
Cenozoic by Ciro Santilli 35 Updated +Created
Era by Ciro Santilli 35 Updated +Created
List of rocks by Ciro Santilli 35 Updated +Created
Mitochondrial DNA mutates faster than nuclear DNA by Ciro Santilli 35 Updated +Created
Wikipedia mentions "Since animal mtDNA evolves faster than nuclear genetic markers" with a few sources.
Some sources:
The Spiders' Web: Britain's Second Empire by Ciro Santilli 35 Updated +Created
Video 1.
The Spider's Web: Britain's Second Empire
. Source.
2017. Directed by Michael Oswald. Adam Curtis vibes.
Some notable points:
Country in Oceania by Ciro Santilli 35 Updated +Created
Golden Triangle (Southeast Asia) by Ciro Santilli 35 Updated +Created
Equity (finance) by Ciro Santilli 35 Updated +Created
Vertebrate by Ciro Santilli 35 Updated +Created
The big breakthrough of the vertebrates appears to be the ability to swim around in a straight line and eat smaller species that are floating about.
Bones appear to help that a lot!
It is likely the most efficient design to travel long distances. Be thin and wiggle your tail around.
Perhaps smaller animals can skip the bone thing. Maybe a notable example are the lancelets, which look a bit like small fish. But they only go up to 8 cm.
GPL software by Ciro Santilli 35 Updated +Created
CC BY-NC-ND 4.0 table of contents by Ciro Santilli 35 Updated +Created
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!
Video 1.
Intro to OurBigBook
. Source.
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
    Video 2.
    OurBigBook Web topics demo
    . Source.
  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:
    • 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
    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 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.
  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