This paper appears to calculate the Schrödinger equation solution for the hydrogen atom.
TODO is this the original paper on the Schrödinger equation?
Published on Annalen der Physik in 1926.
Open access in German at: onlinelibrary.wiley.com/doi/10.1002/andp.19263840404 which gives volume 384, Issue 4, Pages 361-376. Kudos to Wiley for that. E.g. Nature did not have similar policies as of 2023.
This paper may have fallen into the public domain in the US in 2022! On the Internet Archive we can see scans of the journal that contains it at: ia903403.us.archive.org/29/items/sim_annalen-der-physik_1926_79_contents/sim_annalen-der-physik_1926_79_contents.pdf. Ciro Santilli extracted just the paper to: commons.wikimedia.org/w/index.php?title=File%3AQuantisierung_als_Eigenwertproblem.pdf. It is not as well processed as the Wiley one, but it is of 100% guaranteed clean public domain provenance! TODO: hmmm, it may be public domain in the USA but not Germany, where 70 years after author deaths rules, and Schrodinger died in 1961, so it may be up to 2031 in that country... messy stuff. There's also the question of wether copyright is was tranferred to AdP at publication or not.
An early English translation present at Collected Papers On Wave Mechanics by Deans (1928).
Contains formulas such as the Schrödinger equation solution for the hydrogen atom (1''):where:
In order for there to be numerical agreement, must have the value
, are the charge and mass of the electron
As mentioned on the Wikipedia page en.wikipedia.org/w/index.php?title=Stationary_Action_Principle&oldid=1020413171, "principle of least action" is not accurate since it could not necessarily be a minima, we could just be in a saddle-point.
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.
Ciro's theory for his disappearance is that he became a Majorana fermion and flew off into the infinite.
Participated in the German nuclear weapons program, ouch.
This is about the polarization of a string in 3D space. That is the first concept of polarization you must have in mind!
One big advantage over FreeFem is that it uses plain old Python to describe the problems instead of a domain-specific language. Matplotlib is used for plotting by default, so we get full Python power out of the box!
Also uses variational formulation of a partial differential equation like FreeFem which is a pain.
One downside is that its documentation is a Springer published PDF link.springer.com/content/pdf/10.1007%2F978-3-319-52462-7.pdf which is several years out-of-date (tested with FEnics 2016.2. Newbs. This causes problems e.g.: stackoverflow.com/questions/53730427/fenics-did-not-show-figure-nameerror-name-interactive-is-not-defined/57390687#57390687
system of partial differential equations are mentioned at: link.springer.com/content/pdf/10.1007%2F978-3-319-52462-7.pdf 3.5 "A system of advection–diffusion–reaction equations". You don't need to manually iterate between the equations.
On Ubuntu 20.04 as per fenicsproject.org/download/Before 2020-06, it was failing with:but they seem to have created the Ubuntu 20.04 package as of 2020-06, so it now worked! askubuntu.com/questions/866901/what-can-i-do-if-a-repository-ppa-does-not-have-a-release-file
sudo apt-get install software-properties-common
sudo add-apt-repository ppa:fenics-packages/fenics
sudo apt-get update
sudo apt-get install --no-install-recommends fenics
sudo apt install fenics
python3 -m pip install -u matplotlib
E: The repository 'http://ppa.launchpad.net/fenics-packages/fenics/ubuntu focal Release' does not have a Release file.
TODO heat equation hello world.
Feynman was a huge womanizer during a certain period of his life Updated 2025-01-10 +Created 1970-01-01
Feynman became a terrible womanizer after his first wife Arline Greenbaum died, involving himself with several married women, and leading to at least two abortions according to Genius: Richard Feynman and Modern Physics by James Gleick (1994).
Ciro Santilli likes to think that he is quite liberal and not a strict follower of Christian morals, but this one shocked him slightly even. Feynman could be a God, but he could also be a dick sometimes.
One particular case that stuck to Ciro Santilli's mind, partly because he is Brazilian, is when Feynman was in Brazil, he had a girlfriend called Clotilde that called him "Ricardinho", which means "Little Richard"; -inho is a diminutive suffix in Portuguese, and also indicates affection. At some point he even promised to take her back to the United States, but didn't in the end, and instead came back and married his second wife in marriage that soon failed.
Richard's third and final wife, Gweneth Howarth, seemed a good match for him though. When they started courting, she made it very clear that Feynman should decide if he wanted her or not soon, because she had other options available and being actively tested. Fight fire with fire.
There are unlisted articles, also show them or only show them.