Hall effect experimental diagram
. Source. The Hall effect refers to the produced voltage , AKA on this setup.An intuitive video is:
The key formula for it is:where:
- : current on x direction, which we can control by changing the voltage
- : strength of transversal magnetic field applied
- : charge carrier density, a property of the material used
- : height of the plate
- : electron charge
Applications:
- the direction of the effect proves that electric currents in common electrical conductors are made up of negative charged particles
- measure magnetic fields, TODO vs other methods
Other more precise non-classical versions:
Inward Bound by Abraham Pais (1988) by 
Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01The book unfortunately does not cover the history of quantum mechanics very, the author specifically says that this will not be covered, the focus is more on particles/forces. But there are still some mentions.
Open access at the University of Oxford by Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01Things actually have gotten more and more closed, e.g. of stuff getting paywalled with time:
It appears that things got really bad starting in 2017, possibly when WebLearn was introduced. When things migrated to Canvas, they were closed by default, apparently with any mechanism to publish publicly.
Therefore, they managed to make things more closed than when teachers would just upload to good old
ox.ac.uk/~name static websites!!Ciro Santilli has also heard that some people in the Mathematical Institute of the University of Oxford opposed to moving away from their Moodle instance precisely because the new options did not support open publishing, so kudos to those people. But most teachers likely don't care and just do whatever is the best internally supported default.
Their "open" video material: podcasts.ox.ac.uk/ A somewhat small part is Creative Commons, but most proprietary. Despite the name "podcasts", they do contain video, it is just a relic.
podcasts.ox.ac.uk/open contains actual Creative Commons only it seems.
It does however appear that professors own their lecture notes, so there some hope maybe: governance.admin.ox.ac.uk/legislation/statute-xvi-property-contracts-and-trusts#collapse1383636
Talks: talks.ox.ac.uk/. Mathematical, Physical and Life Sciences (MPLS) subset: talks.ox.ac.uk/talks/department/id/oxpoints:23232639
University of Oxford documentary by the British Council (1941)
Source. Oxford virtual learning environment by Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01Their status is a mess as of 2020s, with several systems ongoing. Long live the "original" collegiate university!
Not really dedicated to open source course material, nor to free courses...
The "Open" in its name only made sense in the 60's, when it was founded, nowadays, there isn't much about this institution that is very different compared to traditional Oxbridge. "Cheap more online university" would be a more adequate name for it.
A system that would truly live up to the name "Open" in the year 2020 is the one described at the ideal university by Ciro Santilli.
Wikipedia even says that the initial focus was on broadcasting learning material on television and radio, so what happened to that now that we have an even more powerful on-demand tool called Internet!
They even created their own MOOC website, FutureLearn. But www.freecodecamp.org/news/massive-open-online-courses-started-out-completely-free-but-where-are-they-now-1dd1020f59/ mentions:OMG. God why.
The course content is still free to access, but it’s only available for the duration of the course, and for two weeks after it ends.
A few open sources at: www.open.edu/openlearn/free-courses. The 5-hour course on particle physics says it all. Stated as of 2023 at www.open.ac.uk/about/open-educational-resources/openlearn/free-learning:
www.youtube.com/watch?v=Pj0rbafFBak What's an Open University Degree Like? by Luke Cutforth (2021) mentions that it is more autodidactic/online, and it encourages part time learning.
youtu.be/rsWwffX-u0A?t=99 Open University - How does it work? by Matt Greg Vlogs (2017) shows that they do have their own custom institutional material. And it is not open???? Please. youtu.be/rsWwffX-u0A?t=222 mentions that there is no entry exam, and you can change your courses at any time, that is good at least.
Israel apparently also created their own version in the 70's inspired by the British one: Open University of Israel. Same story it seems.
In retrospect, doing electrical engineering (and likey the other engineering degrees) felt like taking a trip to the 60s in the United States, due to both the subject matter, and how old the concrete buildings were!
This does not need to be a bad thing. It is in that era (and earlier) that much of the exciting foundations of the field were set, and there is great value in there is value in tutorials written by early pioneers of the field. Not that they were amazing at excting history lessons as they should be. But the course outline suggested that intent.
But that point of view must also be accompanied by the excitement of the great ongoing advances of technology (and impact they had in the past). And on that, they failed.
Quantum computing university course by Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-04-24 +Created 1970-01-01Requires entangled particles, unlike BB84 which does not.
All of them need a vacuum because you can't shoot elecrons through air, as mentioned at Video "50,000,000x Magnification by AlphaPhoenix (2022)".
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!
Intro to OurBigBook
. Source. 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/derivativeVideo 2. OurBigBook Web topics demo. Source. - 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 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. 
- Infinitely deep tables of contents:
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