Order of the highest derivative that appears.
Only people who need to drive a car should be allowed to drive a car anywhere near a city, e.g. people who work door to door, people who are disabled, etc.
Countryside driving is fine. If going to a city, you just have to drive to a parking outside of the city where you then take the public transport. And those who live in cities must leave their cars there too.
Everyone else must walk or cycle from home to public transport.
Cars just destroy everything, they make everything ugly:
- this was extremely clear to Ciro Santilli as a cyclist. He previously lived in a place with few cars and the countryside was so pleasant. Then he moved to a place with more cars and it was shocking. It's a mixture of pollution, noise, and the fact that roads cut up the countryside that just make things not pleasant at all. Dual lane roads in particular are just a terrible thing. You can hear them from afar, much before you see them.You can just see as tiny little villages surrounding the bit city and it's oversized motorways are more or less homogenized into one big city mass, the process is clearly visible as you cycle out of the big city and the villages become nicer and more unique as you go along further out.
- even within cities, cars completely dehumanize the streets. For example, Ciro once lived in a small dead end street, and he would have gladly opened his front window more often to meet the neighbours. But just the noise of cars passing by every so often makes it impractical to work like that.
The Zatoichi effect applies well to the problem of cyclists:This is the main drama faced by cyclists.
- they are not really pedestrians, and pedestrian paths are not suitable to them because they are too narrow, of not smooth, or curved. But pedestrians will always have enough political power to have their paths, because they live around the paths
- they are not really motor vehicles, because motor vehicle paths are too wide and too fast for them. But motor vehicles will always have enough political power to have their paths, because people are lazy and stupid, and because as the world stands, individually you just don't have any reasonable choice to go anywhere.
Lobbying groups:
Given a function :we want to find the points of the domain of where the value of is smaller (for minima, or larger for maxima) than all other points in some neighbourhood of .
- from some space. For beginners the real numbers but more generally topological spaces should work in general
- to the real numbers
In the case of Functionals, this problem is treated under the theory of the calculus of variations.
They do seem to have been very innovative, and have had a very good work culture. They also had a huge impact on the Silicon Valley startup scene.
Some products they are known for:
- oscilloscopes
- Atomic clocks, notably highly portable ones, see e.g. Video "Inside the HP 5061A Cesium Clock by CuriousMarc (2020)"
- pocket calculator
These people have good intentions.
The problem is that they don't manage to go critical because there's to way for students to create content, everything is manually curated.
You can't even publicly comment on the textbooks. Or at least Ciro Santilli hasn't found a way to do so. There is just a "submit suggestion" box.
This massive lost opportunity is even shown graphically at: cnx.org/about (archive) where there is a clear separation between:Maybe this wasn't the case in their legacy website, legacy.cnx.org/content?legacy=true, but not sure, and they are retiring that now.
- "authors", who can create content
- "students", who can consume content
Thus, OurBigBook.com. License: CC BY! So we could re-use their stuff!
By Rice University.
TODO what are the books written in?
- github.com/openstax/openstax-cms Uses Wagtail CMS. So presumaby they just Wagtail's WYSIWYG.
- github.com/openstax/os-webview
The Holy Hand Grenade of Antioch scene from Monty Python and the Holy Grail
. Source. When a young Ciro Santilli played Worms Armageddon, he almost shat himself of laughter when he first threw a Holy Grenade. Little did he know it was actually a Monty Python reference.Black Knight scene from Monty Python and the Holy Grail
. Source. The Insulting Frenchman scene from Monty Python and the Holy Grail
. Source. Execution in Russia by Monty Python
. Source. Ciro Santilli's admiration for Dyson goes beyond his "unify all the things approach", which Ciro loves, but also extends to the way he talks and the things he says. Dyson is one of Ciro's favorite physicist.
Besides this, he was also very idealistic compassionate, and supported a peaceful resolution until World War II with United Kingdom was basically inevitable. Note that this was a strategic mistake.
Dyson is "hawk nosed" as mentioned in Genius: Richard Feynman and Modern Physics by James Gleick (1994) chapter "Dyson". But he wasn't when he was young, see e.g. i2.wp.com/www.brainpickings.org/wp-content/uploads/2016/03/freemandyson_child-1.jpg?resize=768%2C1064&ssl=1 It sems that his nose just never stopped growing after puberty.
He also has some fun stories, like him practicing night climbing while at Cambridge University, and having walked from Cambridge to London (~86km!) in a day with his wheelchair bound friend.
Ciro Santilli feels that the label child prodigy applies even more so to him than to Feynman and Julian Schwinger.
Bibliography:
- QED and the men who made it: Dyson, Feynman, Schwinger, and Tomonaga by Silvan Schweber (1994) chapter 9 Freeman Dyson and the Structure of Quantum Field Theory
Like all big names in science, she was at the right place at the right time and with the right interest and passion.
Notably, the man she married, Pierre Curie, happened to be a the world master at precisely the technique that she needed to carefully measure radioactivity: he had the most precise electrometers in the world, which allowed to detect small amounts of radioactivity via the ionization of air by radiation . These used piezoelectricity, which Pierre Curie co-discovered with his brother.
Marie Curie section of The Mystery of Matter episode 2
. Source. Fantastic illustration of Marie's life and work!- youtu.be/wbuDmY5gpXQ?t=2041 she specifically avoided X-ray research because she felt that there was too much competition in that area. TODO find a written reference about that and add it to Wikipedia.
Marie Curie c. 1920
. Source. 
Journals must require source code and data sets to publish Updated 2025-03-08 +Created 1970-01-01
It is understandable that you might not be able to reproduce a paper that does a natural science experiment, given that physics is brutal.
But for papers that have either source code or data sets, academic journals must require that those be made available, or refuse to publish.
Any document without such obvious reproducibility elements is a white paper, not a proper peer reviewed paper.
Naming taxonomic ranks like genus, domain, etc. is a fucking waste of time, only useful before we developed molecular biology.
All that matters is the tree of clades with examples of species in each clade, and common characteristics shared by the clade.
And with molecular biology, we can build those trees incredibly well for extant species. When extinct species are involved however, things get more complicated.
This dude mentored Enrico Fermi in high school. Ciro Santilli added some info to Fermi's Wikipedia page at: en.wikipedia.org/w/index.php?title=Enrico_Fermi&type=revision&diff=1050919447&oldid=1049187703 from Enrico Fermi: physicist by Emilio Segrè (1970):
In 1914, Fermi, who used to often meet with his father in front of the office after work, met a colleague of his father called Adolfo Amidei, who would walk part of the way home with Alberto [Enrico's father]. Enrico had learned that Adolfo was interested in mathematics and physics and took the opportunity to ask Adolfo a question about geometry. Adolfo understood that the young Fermi was referring to projective geometry and then proceeded to give him a book on the subject written by Theodor Reye. Two months later, Fermi returned the book, having solved all the problems proposed at the end of the book, some of which Adolfo considered difficult. Upon verifying this, Adolfo felt that Fermi was "a prodigy, at least with respect to geometry", and further mentored the boy, providing him with more books on physics and mathematics. Adolfo noted that Fermi had a very good memory and thus could return the books after having read them because he could remember their content very well.
Ciro Santilli really likes guys like this. Given that he does not have the right genetics, conditions and temperance for scientific greatness in this lifetime, he dreams of one day finding his own Fermi instead.
Like everything else in Lie groups, first start with the matrix as discussed at Section "Lie algebra of a matrix Lie group".
Intuitively, a Lie algebra is a simpler object than a Lie group. Without any extra structure, groups can be very complicated non-linear objects. But a Lie algebra is just an algebra over a field, and one with a restricted bilinear map called the Lie bracket, that has to also be alternating and satisfy the Jacobi identity.
Another important way to think about Lie algebras, is as infinitesimal generators.
Because of the Lie group-Lie algebra correspondence, we know that there is almost a bijection between each Lie group and the corresponding Lie algebra. So it makes sense to try and study the algebra instead of the group itself whenever possible, to try and get insight and proofs in that simpler framework. This is the key reason why people study Lie algebras. One is philosophically reminded of how normal subgroups are a simpler representation of group homomorphisms.
To make things even simpler, because all vector spaces of the same dimension on a given field are isomorphic, the only things we need to specify a Lie group through a Lie algebra are:Note that the Lie bracket can look different under different basis of the Lie algebra however. This is shown for example at Physics from Symmetry by Jakob Schwichtenberg (2015) page 71 for the Lorentz group.
- the dimension
- the Lie bracket
As mentioned at Lie Groups, Physics, and Geometry by Robert Gilmore (2008) Chapter 4 "Lie Algebras", taking the Lie algebra around the identity is mostly a convention, we could treat any other point, and things are more or less equivalent.
This is meant to be an answer to: diy.stackexchange.com/questions/27669/how-can-i-thoroughly-blackout-a-bedroom-window-on-a-budget but that question was protected and I can't answer right now because I don't have 10 reputation on the website, so here goes.
Off-the-shelf techniques to become a teaching superhero.
Customized website idea at: OurBigBook.com.
Like all poor countries, Brazil's lack of money and scientific culture severely limit its ability to make technological and scientific advances.
While this sounds obvious, Ciro Santilli has felt it first hand since he moved from Brazil to Europe, and it is just shocking.
In the city of Santos for example, despite being a dream place from the natural point of view, it would be completely impossible to achieve any deep tech technical advance that impacts the world. In Europe however, there are several several places where this can happen.
The proper precise definition of mathematics can be found at: Section "Formalization of mathematics".
The most beautiful things in mathematics are described at: Section "The beauty of mathematics".
Study Hilbert spaces desert dilemma meme
. Source. Applies to almost all of mathematics of course. But we don't care, do we!Ciro Santilli is a fan of this late 2010's buzzword.
It basically came about because of the endless stream of useless software startups made since the 2000's by one or two people with no investments with the continued increase in computers and Internet speeds until the great wall was reached.
Deep tech means not one of those. More specifically, it means technologies that require significant investment in expensive materials and laboratory equipment to progress, such as molecular biology technologies and quantum computing.
And it basically comes down to technologies that wrestle with the fundamental laws of physics rather than software data wrangling.
Computers are of course limited by the laws of physics, but those are much hidden by several layers of indirection.
Full visibility, and full control, make computer tasks be tasks that eventually always work out more or less as expected.
The same does not hold true when real Physics is involved.
Physics is brutal.
To start with, you can't even see your system very clearly, and often doing so requires altering its behaviour.
For example, in molecular biology, most great discoveries are made after some new technique is made to be able to observe smaller things.
But you often have to kill your cells to make those observations, which makes it very hard to understand how they work dynamically.
What we would really want would be to track every single protein as it goes about inside the cell. But that is likely an impossible dream.
The same for the brain. If we had observations of every neuron, how long would it take to understand it? Not long, people are really good at reverse engineering things when there is enough information available to do so, see also science is the reverse engineering of nature.
Then, even when you start to see the system, you might have a very hard time controlling it, because it is so fragile. This is basically the case of quantum computing in 2020.
It is for those reasons that deep tech is so exciting.
The next big things will come from deep tech. Failure is always a possibility, and you can't know before you try.
But that's also why its so fun to dare.
Stuff that Ciro Santilli considers "deep tech" as of 2020:
- brain-computer interface
- fusion power. The question there is, when is "deep", "too deep"?
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