In the context of Maxwell's equations, it is vector field that is one of the inputs of the equation.
Section "Maxwell's equations with pointlike particles" asks if the theory would work for pointlike particles in order to predict the evolution of this field as part of the equations themselves rather than as an external element.
Measured in amperes in the International System of Units.
Found through Google with no direct relation known to Ciro Santilli:
- en.wikipedia.org/wiki/Santilli: Wikipedia page of the glorious family, Santillis with their own Wikipedia page:
- Ruggero Santilli: "fringe science guy", by far dominates Google as of 2019. Created the respectable R.M. Santilli Foundation
- Ray Santilli made a fake 1995 alien autopsy movie, YouTube sample: www.youtube.com/watch?v=sVcaT2QnoDs
- Ivana Santilli: Canadian singer, pop-electric-chill: www.youtube.com/watch?v=hQRuVN0H8dM
- accounts on important websites
- github.com/santilli anonymous GitHub as of 2019
- santilli.com/ for rent by realnames.com/ (wiki page) as of 2019
- Also Brazilian and tech related like Ciro Santilli.
- www.youtube.com/user/TheOverthrowShow thepetesantillishow.com/ Pete Santilli, American Conservative news commentator show, makes Ciro cringe of boredom. At least he has a passion.
Possibly related variants:
- Santillo:
- Will Santillo who makes somewhat artistic porn photos. His website with several free demos: santillophotography.com/
- www.linkedin.com/in/ciro-santillo-2025a6ba/ a "Ciro Santillo", github.com/Ciruxx, also a programmer
- Santilly, a town in Saône-et-Loire department, France
- santilly.com/ redirects to www.pompes-funebres-santilly.com/fr/, a French funerary service
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:
In some contexts, we want to observe what happens for a given fixed magnetic field strength on a specific plate (thus and are also fixed).
In those cases, it can be useful to talk about the "Hall resistance" defined as:So note that it is not a "regular resistance", it just has the same dimensions, and is more usefully understood as a proportionality constant for the voltage given an input current:
This notion can be useful because everything else being equal, if we increase the current , then also increases proportionally, making this a way to talk about the voltage in a current independent manner.
And this is particularly the case for the quantum Hall effect, where is constant for wide ranges of applied magnetic field and TODO presumably the height can be made to a single molecular layer with chemical vapor deposition of the like, and if therefore fixed.
A different and more elegant way to express Maxwell's equations by using the:instead of the:
E.g. thinking about the electric potential alone, you could set the zero anywhere, and everything would remain be the same.
The Lorentz gauge is just one such choice. It is however a very popular one, because it is also manifestly Lorentz invariant.
The website system that runs OurBigBook.com. For further information see:Relies on the OurBigBook Library to compile OurBigBook Markup.
- OurBigBook.com: rationale
- cirosantilli.com/ourbigbook/ourbigbook-web: project documentation
This single experimental observation/idea is the basis for all of special relativity.
Special relativity is the direct result of people bending their backs to accommodate for this really weird fact.
Basically everything that applies to the blogs section also applies here, but university lecture notes are so important to us that they deserve a bit more talk.
It is arguable that this is currently the best way to learn any university subject, and that it can already be used to learn any subject.
We basically just want to make the process more efficient and enjoyable, by making it easier:
One major problem with lecture notes is that, as the name suggests, they are merely a complement to the lecture, and don't contain enough detail for you to really learn solely from them without watching the lecture.
The only texts that generally teach in enough depth are actual books, which are almost always commercial.
So in a sense, this project can be seen as a path to upgrade free lecture notes into full blown free books, from which you can learn from scratch without any external material.
And a major way in which we believe this can be done is through the reuse of sections of lecture notes by from other universities, which greatly reduces the useless effort of writing things from scratch.
The intended mental picture is clear: the topics feature docs.ourbigbook.com/#ourbigbook-web-topics will is intended to act as the missing horizontal topic integration across lecture notes of specific universities, e.g:
MIT calculus course UCLA calculus course
* Calculus <---> * Calculus
* Limit <---> * Limit
* Limit of a function
* Limit of a series <---> * Limit of a series
* Derivative <---> * Derivative
* L'Hôpital's rule
* Integral <---> * Integral
Example topics page of OurBigBook.com
. One important advantage of lecture notes is that since they are written by the teacher, they should match exactly what "students are supposed to learn to get good grades", which unfortunately is a major motivation for student's learning weather we want it or not.
One big open question for this project is to what extent notes written for lectures at one university will be relevant to the lectures at another university?
Is it possible to write notes in a way that they are naturally reusable?
It is our gut feeling that this is possible. But it almost certainly requires an small intentional effort on the part of authors.
The question then becomes whether the "become famous by getting your content viewed in other universities" factor is strong enough to attract users.
And we believe that it might, it just might be.
Bibliography:
- Subtle is the Lord by Abraham Pais (1982) chapter III "Relativity, the special theory" has a good sketch as you may imagine.
Can you just imagine what if luminiferous aether was one single fixed rigid body? This is apparently what Maxwell believed, Subtle is the Lord by Abraham Pais (1982) page 111 quoting his entry to Encyclopedia Britannica:Then it would provide a natural space coordinate for the entire universe!
There can be no doubt that the interplanetary and interstellar spaces are not empty but are occupied by a material substance or body, which is certainly the largest, and probably the most uniform, body of which we have any knowledge.
- HyperCard: we are kind of a "multiuser" version of HyperCard, trying to tie up cards made by different users. It is worth noting that HyperCard was one of the inspirations for WikiWikiWeb, which then inspired Wikipedia
- Semantic Web
- NLab
- physicstravelguide.com/ Nice manifesto: physicstravelguide.com/about by Jakob Schwichtenberg.
- OpenStax
- www.ft.com/content/5515ec3e-0040-4d90-85a9-df19d6e3ebd2 (archive) Twilio’s Jeff Lawson: an evangelist for software developersYou can never be first. But you can have the correct business model. That company's website must have gone into IP Purgatory, and could never be released as an open source website.As a student at the University of Michigan, he started a company that made lecture notes available free online, drawing a large audience of Midwestern college students and, soon enough, advertisers. At the height of the dotcom bubble, he dropped out of college, raised $10m from the venture firm Venrock and moved the company to Silicon Valley.His start-up drew interest from an acquirer that was planning to go public early in 2000. They closed the acquisition but missed their IPO window as the market plunged, and by August the company had filed for bankruptcy. Stock that Lawson and investors in his start-up received from the sale became worthless.He might actually be interested in donating to OurBigBook.com if it move forward now that he's a billionaire.
- Knol: basically the exact same thing by Google but 14 years earlier and declared a failure. Quite ominous:
- leanpub: similar goals, markdown-based, but the usual "you own your book copyright and you are trying to sell your book" approach
- nature Scitable
OK, just going random now:
Pinned article: 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 3. Visual Studio Code extension installation.
Figure 4. Visual Studio Code extension tree navigation.
Figure 5. Web editor. 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. 
- 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