In chess, a pawn structure refers to the arrangement and configuration of pawns on the board, which significantly influences the strategic aspects of a position. The pawn structure is crucial because pawns are the only pieces that cannot move backward, and their positioning can determine the strengths and weaknesses of both sides. Key aspects of pawn structure include: 1. **Pawn Chains**: A diagonal line of pawns supporting each other. They can create strong defensive formations and control key squares.
In chess, the endgame scenario often involves various pieces left on the board when most of the material has been exchanged. One specific endgame that can occur is the "queen and pawn versus queen" endgame. ### Queen and Pawn vs. Queen Endgame 1. **Material Imbalance**: This endgame consists of one player having a queen and a pawn, while the other player has just a queen.
"Solving chess" refers to the process of determining the outcome of a chess game (either a win, loss, or draw) from any given position, assuming perfect play from both players. The ultimate goal of solving chess is to provide a complete analysis of the game, ideally leading to a definitive understanding of whether the game is a win for White, a win for Black, or if it results in a draw, regardless of the moves made by each player.
The 24 puzzle, also known as the 24 game, is a mathematical card game that challenges players to use basic arithmetic operations to combine four numbers in order to reach the value of 24. Each player draws four numbers (which can range from 1 to 9), and then using addition, subtraction, multiplication, or division, they must find a way to achieve the target number of 24.
Fisher's principle, proposed by the evolutionary biologist Ronald A. Fisher in 1930, is a concept in evolutionary theory that explains the sex ratio in sexually reproducing populations. According to Fisher's principle, under stable conditions, the sex ratio of males to females in a population will tend to stabilize at approximately 1:1 (50% males and 50% females). The rationale behind this principle is based on the idea of evolutionary stability.
Equitable cake-cutting refers to a concept in fair division that deals with dividing resources in a way that ensures each participant feels they have received their fair share. The term "cake-cutting" is often used metaphorically to describe the division of a divisible resource (the "cake"), whether it's physical (like a real cake) or abstract (like time, money, or property).
Fair river sharing refers to the equitable distribution and management of water resources from rivers among different users, stakeholders, or regions. It encompasses legal, social, and technical measures to ensure that all parties—such as agriculture, industry, municipalities, and ecosystems—receive a fair allocation of water based on their needs, rights, and contributions to sustainability.
The "Problem of the Nile" typically refers to the historical and ongoing disputes over the management and use of the waters of the Nile River, particularly among the countries that rely on it for their water supply. The Nile is one of the longest rivers in the world and flows through multiple countries, including Uganda, Sudan, and Egypt.
The MDA framework stands for Mechanics, Dynamics, and Aesthetics. It is a conceptual framework used in game design and analysis to understand how different elements of a game interact and contribute to the overall player experience. The framework was introduced by Andrew Clement as a way to explore and design games more effectively. 1. **Mechanics**: This refers to the rules and systems of the game.
Three-dimensional space, often referred to as 3D space, is a geometric construct that extends the concept of two-dimensional space into an additional dimension. In 3D space, objects are defined by three coordinates, typically represented as (x, y, z). Each coordinate represents a position along one of the three perpendicular axes: 1. **X-axis**: Typically represents width, corresponding to left-right movements. 2. **Y-axis**: Typically represents height, corresponding to up-down movements.
Elliptic geometry is a type of non-Euclidean geometry characterized by its unique properties and the nature of its parallel lines. In contrast to Euclidean geometry, where the parallel postulate states that through a point not on a given line, there is exactly one line parallel to the given line, in elliptic geometry, there are no parallel lines at all. Every pair of lines eventually intersects.
Theodosius of Bithynia was an ancient Greek mathematician and astronomer who lived around the 2nd century BCE, during the Hellenistic period. He is best known for his contributions to the field of astronomy, particularly for his work in the development of star catalogs. Theodosius is credited with the creation of one of the earliest known star catalogs, which was significant in the study of celestial navigation and astronomy at the time.
The Cassini–Huygens mission was a collaborative project between NASA, the European Space Agency (ESA), and the Italian Space Agency (ASI) aimed at studying Saturn and its moons, particularly Titan, Saturn's largest moon. The mission consisted of two main components: 1. **Cassini Orbiter**: Launched on October 15, 1997, the Cassini spacecraft entered orbit around Saturn on July 1, 2004.
André Weil was a prominent French mathematician, born on May 6, 1906, and he passed away on August 6, 1998. He made significant contributions to various areas of mathematics, particularly in algebraic geometry, number theory, and topology. Weil is perhaps best known for his work on algebraic varieties and his development of Weil conjectures, which link algebraic geometry with number theory and have profound implications in both fields.
William Wallace was a Scottish mathematician and philosopher best known for his work in mathematics and his contributions to the early development of calculus and logic in the late 17th century. He was born in 1663 and died in 1724. Wallace's significant contributions include his work on the calculus of infinitesimals and the development of early mathematical notation.

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