A dust devil is a small,旋转的气旋,通常在干燥、沙质或尘土飞扬的地面上形成。它们通常是一个相对较小的气象现象,通常高度在几米到几十米之间,直径从几英尺到几十英尺不等。尘土旋风的形成通常需要强烈的太阳辐射,使地面的空气升温并迅速上升,产生
Quantum supremacy refers to the point at which a quantum computer can perform a calculation that is infeasible for even the most powerful classical supercomputers. It signifies a significant milestone in the field of quantum computing, demonstrating that quantum systems can solve certain problems more efficiently than classical systems. The term gained prominence in 2019 when Google announced that it had achieved quantum supremacy with its quantum processor, Sycamore.
An NS5-brane, or Neveu-Schwarz five-brane, is a type of extended object in string theory. Branes, which are short for "membranes," can exist in various dimensions, and they play a crucial role in the framework of string theory, particularly in understanding non-perturbative aspects of the theory.
Hall algebra is a mathematical structure that arises in the context of category theory and representation theory, particularly in the study of representations of finite groups and combinatorial structures. It is named after Philip Hall, who introduced the concept of Hall systems in the 1930s. At its core, Hall algebra is built on the idea of Hall pairs, which are certain collections of subsets of a finite set that satisfy specific combinatorial properties.
The symmetric product of an algebraic curve is a mathematical construction that generalizes the notion of products of points on the curve. More specifically, if \( C \) is a projective algebraic curve, the symmetric product \( \text{Sym}^n(C) \) of \( C \) is the space that parameterizes unordered \( n \)-tuples of points on the curve, where the points can be repeated.
Lewis Paul was an English inventor and one of the key figures in the development of the mechanized textile industry during the 18th century. He is best known for his invention of the "carding machine" and improvements to the spinning process, which were significant factors in the Industrial Revolution. His inventions helped streamline the production of textiles, making it easier to process raw wool and cotton into yarn.
The Harish-Chandra isomorphism is a fundamental result in the representation theory of Lie groups and Lie algebras, particularly in the context of semisimple Lie groups. It relates the spaces of invariant differential operators on a symmetric space to the space of functions on the Lie algebra of the group. More specifically, consider a semisimple Lie group \( G \) and a maximal compact subgroup \( K \).
Markov's inequality is a result in probability theory that provides an upper bound on the probability that a non-negative random variable is greater than or equal to a positive constant. The inequality is named after the Russian mathematician Andrey Markov. The statement of Markov's inequality is as follows: Let \(X\) be a non-negative random variable (i.e., \(X \geq 0\)), and let \(a > 0\) be a positive constant.
Europe by Ciro Santilli 40 Updated 2025-07-16
For the most part, a great pseudo-country to live in with lots of cultural diversity, art and safety.
However, Europe is in economic decline after all its Jewish and German geniuses fled in/after World War II and due to having more than one natural language is bad for the world.
The Poincaré–Bendixson theorem is a fundamental result in the field of dynamical systems, particularly concerning the behavior of continuous dynamical systems in two dimensions. It addresses the long-term behavior of trajectories in a planar (2-dimensional) system described by a set of ordinary differential equations.
In the year 2000, Ciro lived with his parents for 10 months in the Coventry because his father took some courses at the University of Warwick. This was Ciro's most important educational experience, more so than any other inCiro Santilli's formal education, because it taught him the Holy Language of English, which infinitely expanded Ciro's Internet horizons, and shaped Ciro's having more than one natural language is bad for the world philosophy. When he came back to Brazil, Ciro skipped dozens of levels in his English school in Santos, São Paulo, Brazil, a Brazilian chain called Cultura Inglesa, and was put to study with much older teenagers who marveled at Ciro's incredibly cute, but since lost, British accent.
Another huge advantage of Coventry is that the Hearsall Community Primary School where Ciro studied was a regular British primary school but with two classes dedicated to foreign students to learn English before integrating with the British students. There were a several kids from Kosovo there due to the Kosovo War which was just ending, and it was there that Ciro made his first Chinese friend, yet unaware of course of the role the country would later play in his life. One particularly fun memory was that of playing soccer on the school playground with a sponge ball to avoid breaking the windows. Then one day it was raining, british weather of course, but Ciro still went for a header, and the soaked sponge ball was soaked and splashed Ciro with dirty water all over. Good days.
Ciro also played a bit of Rugby in those days in a local club.
Some other good memories are of reading the first two Harry Potters, playing and mostly watching other kids play Pokemon on their Game Boys and Pokemon trading cards, and going to a nearby commons playing field and woods, as it typical throughout the UK. Ciro also played some rugby with a local boys team TODO name? but for some reason his team was always crushed when they went to nearby towns to play against other teams. And Ciro also went with his family or with school to some nearby attractions, like Stratford-Upon-Avon (Shakespeare's hometown), and some castles.
Video 1.
When Ali G met the Beckhams by Comic Relief (2001)
Source. Ciro's father really liked Ali G. when they were in the UK in the year 2000, and Ciro would watch along, not fully getting all jokes, but still amused by his irreverence. This interview with David and Victoria Beckham is perhaps one of Ali's best performances.
Video 2.
Wicked wicked jungle is massive song from Ali G Indahouse (2002)
Source. OK, the last Ali G video, I promise. Maybe. This video illustrate well the main point of Ali G's humour: his cultural appropriation of American black rap/crime culture, despite it being entirely incongruence with his British background.
Moral injury refers to the psychological, emotional, or spiritual harm that occurs when individuals violate their own moral or ethical beliefs, often in situations where they feel they cannot act in accordance with their values. It is commonly discussed in contexts such as military combat, healthcare, and other high-stress professions where individuals may be faced with morally challenging decisions.
The Heinz dilemma is a moral problem that was introduced by psychologist Lawrence Kohlberg as part of his theory of moral development. The dilemma is presented as a scenario involving a man named Heinz whose wife is suffering from a terminal illness. The only way to save her is to obtain a drug that is very expensive, and the druggist who developed it is charging more than Heinz can afford.
Puritanical bias refers to a mindset or perspective that is influenced by the moral and ethical standards associated with Puritanism, a religious reform movement that originated in the late 16th and 17th centuries, primarily in England. Puritans emphasized values such as strict morality, religious discipline, and a focus on piety and virtue in both personal conduct and societal norms.

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!
We have two killer features:
  1. 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-calculus
    Articles 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
  2. 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.
    Figure 2.
    You can publish local OurBigBook lightweight markup files to either https://OurBigBook.com or as a static website
    .
    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.
  3. https://raw.githubusercontent.com/ourbigbook/ourbigbook-media/master/feature/x/hilbert-space-arrow.png
  4. Infinitely deep tables of contents:
    Figure 6.
    Dynamic article tree with infinitely deep table of contents
    .
    Descendant 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