Doing physics means calculating a number by 
Ciro Santilli 35 Updated 2025-01-29 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-01-29 +Created 1970-01-01In Physics, in order to test a theory, you must be able to extract a number from it.
It does not matter how, if it is exact, or numerical, or a message from God: a number has to come out of the formulas in the end, and you have to compare it with the experimental data.
Many theoretical physicists seem to forget this in their lectures, see also: Section "How to teach and learn physics".
This section is about functions that operates on arbitrary sets.
Ciro Santilli's eulogy: effortless effort
If session autosave was finally mainlined, this would be Nirvana.
When Ciro finally understood that this is a play on Larry Page's name (of course it is, typical programmer/academic humor stuff), his mind blew.
Higher spin multiplicity means lower energy. I.e.: you want to keep all spins pointin in the same direction.
Confusingly, in LaTeX:
\varepsilonrendered , is the default modern Greek glyph\epsilonrendered is the lunate variant
The ELF standard specifies multiple file formats:
- Object files (
.o).Intermediate step to generating executables and other formats:Source code | | Compilation | v Object file | | Linking | v ExecutableObject files exist to make compilation faster: withmake, we only have to recompile the modified source files based on timestamps.We have to do the linking step every time, but it is much less expensive.
- Executable files (no standard Linux extension).This is what the Linux kernel can actually run.
- Archive files (
.a).Libraries meant to be embedded into executables during the Linking step.
- Shared object files (
.so).Libraries meant to be loaded when the executable starts running.
- Core dumps.Such files may be generated by the Linux kernel when the program does naughty things, e.g. segfault.They exist to help debugging the program.
In this tutorial, we consider only object and executable files.
Kind of a synonym for hydrogen emission spectrum not very clear if fine structure is considered by this term or not.
A line set for hydrogen spectral line.
Formula discovered in 1885, was it the first set to have an empirical formula?
The steps are sorted in roughly chronological order. The project might fail at any point, and some steps may be carried in parallel:
- make OurBigBook Markup good enough, to the point that it allows to create a static version of the website, which is used to prototype certain ideas, and for Ciro to start writing test content.Status March 2022: reached a point that it is already highly usable. The following website may continue.
- create a basic implementation of the website, without advanced features like PageRank sorting and WYSIWYG. This is not much more than a blog with some extra metadata, so it is definitely achievable with constrained resources.
- find a university teacher would would like to try it out.Ciro would like to volunteer to work for free for this teacher and students to help the students learn.He would like act like a "super student" who has a lot of free time and motivation.Ciro would start by mapping the headers of the lecture notes onto the website, and then slowly adding content as he feels the need to improve certain explanations.Finding teachers willing to allow this will be a major roadblock: how to convince teachers to use CC BY-SA.If such enlightened teacher is found, it will allow for the initial validation of the website, to decide what kind of tweaking the idea might need, and start uploading quality technical content to the site.
- once some level of validation as been done, Ciro will start looking for charitable charitable grant opportunities more aggressively
- if things seem to be working, start adding more advance features: PageRank-like ranking sorting and WYSIWYG editingThe recommendation algorithms notably is left for a second stage because it needs real world data to be tested. And at the beginning, before Eternal September kicks in, there would be few posts written by well educated university students, so a simple sort by upvote would likely be good enough.
Ciro decided to start with a decent markup language with a decent implementation: OurBigBook Markup. Once that gets reasonable, he will move on to another attempt at the website itself.
The project description was originally at: github.com/cirosantilli/write-free-science-books-to-get-famous-website but being migrated here. The original working project name was "Write free books to get famous website", until Ciro decided to settle for
OurBigBook.com and fixed the domain name. HyperNormalisation by Adam Curtis (2016) by Ciro Santilli 35 Updated 2025-01-29 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-01-29 +Created 1970-01-01 Solutions of the Schrodinger equation by Ciro Santilli 35 Updated 2025-01-29 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-01-29 +Created 1970-01-01As always, the best way to get some intuition about an equation is to solve it for some simple cases, so let's give that a try with different fixed potentials.
"Barys" means "heavy" in Greek, because protons and neutrons was what made most of the mass of known ordinary matter, as opposed notably to electrons.
Baryons can be contrasted with:
- mesons, which have an even number of elementary particles. The name meson comes from "medium" since their most common examples have two quarks rather than three as the most common baryons such as protons. So they have less mass than a proton, but more than an electron, this medium mass.
- leptons, which are much lighter particles such as the electron. "Leptos" means "fine, small, thin".
Basically the same as matrix mechanics it seems, just a bit more generalized.
- eol.org/ Encyclopedia of Life
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