As of the 20th century, this can be described well as "the phenomena described by Maxwell's equations".
Back through its history however, that was not at all clear. This highlights how big of an achievement Maxwell's equations are.
This is about the polarization of a string in 3D space. That is the first concept of polarization you must have in mind!
Two Photon Microscopy by Nemonic NeuroNex (2019)
Source. Shows a prototype of a two-photon electron microscope on an optical table, and describes it in good detail, well done.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.Resonance is a really cool thing.
Examples:
- mechanical resonance, notably:
- pipe instruments
- electronic oscillators, notably:
- LC oscillator, and notably the lossy version RLC circuit
Perhaps a key insight of resonance is that the reonant any lossy system tends to look like the resonance frequency quite quickly even if the initial condition is not the resonant condition itself, because everything that is not the resonant frequency interferes destructively and becomes noise. Some examples of that:
- striking a bell or drum can be modelled by applying an impuse to the system
- playing a pipe instrument comes down to blowing a piece that vibrates randomly, and then leads the pipe to vibrate mostly in the resonant frequency. Likely the same applies to bowed string instruments, the bow must be creating a random vibration.
- playing a plucked string instrument comes down to initializing the system to an triangular wave form and then letting it evolve. TODO find a simulation of that!
Another cool aspect of resonance is that it was kind of the motivation for de Broglie hypothesis, as de Broglie was kind of thinking that electroncs might show discrete jumps on atomic spectra because of constructive interference.
One of its main applications is to determine the 3D structure of proteins.
Sometimes you are not able to crystallize the proteins however, and the method cannot be used.
Crystallizing is not simple because:
- you need a considerable amount of the protein
- sometimes it only crystallizes if you add some extra small chemical that stabilizes it
Cryogenic electron microscopy can sometimes determine the structures of proteins that failed crystallization.
Powder vs single crystal X-ray crystallography by
Ciro Santilli 35 Updated 2025-03-28 +Created 1970-01-01
- 1958: myoglobin structure resolution (1958). The first protein to be resolved.
- 1965: lysozyme structure resolution (1965). The second protein to be resolved.
Crystallography determination with a transmission electron microscopy instead of the more classical X-ray crystallography.
- micro.magnet.fsu.edu/index.html OLD website with great design and much love. Some notable things:
The World Of Enrico Fermi by Harvard Project Physics (1970) by
Ciro Santilli 35 Updated 2025-03-28 +Created 1970-01-01
The World Of Enrico Fermi by Harvard Project Physics (1970)
Source. Microscope Project (YouTube channel) by
Ciro Santilli 35 Updated 2025-03-28 +Created 1970-01-01
As of 2022, this channel is still finding its feet. But it has promise.
Unfortunately it does not show sample preparation, and it does not use controlled cultures, so we are never sure which species are represented.
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