A Turing machine is a theoretical computational model introduced by the mathematician and logician Alan Turing in 1936. It is a fundamental concept in computer science and is used to understand the limits of what can be computed. A Turing machine consists of the following components: 1. **Tape**: An infinite tape that serves as the machine's memory. The tape is divided into discrete cells, each of which can hold a symbol from a finite alphabet.
The Affine Grassmannian is a mathematical object that arises in the fields of algebraic geometry and representation theory, particularly in relation to the study of loop groups and their associated geometric structures. It can be understood as a certain type of space that parametrizes collections of subspaces of a vector space that can be defined over a given field, typically associated with the field of functions on a curve.
In the context of differential geometry, acceleration refers to the derivative of the tangent vector along a curve.
A slurry pump is a type of pump designed to handle the transfer of slurry, which is a mixture of solids and liquids, typically water. Slurry pumps are used in various industries, including mining, mineral processing, wastewater treatment, and chemical processing, to move abrasive and viscous fluids that contain particles such as sand, sludge, and other solids.
Cayley's ruled cubic surface is a notable example in algebraic geometry, particularly relating to cubic surfaces. It is defined as the set of points in projective 3-dimensional space \(\mathbb{P}^3\) that can be expressed as a cubic equation, which is a homogeneous polynomial of degree three in three variables.
A "phraseme" is a linguistic term that refers to a specific type of multi-word expression that conveys a particular meaning that is not directly deducible from the individual words that compose it. Phrasemes can include idioms, fixed phrases, collocations, and other expressions that function as single units of meaning in language.
In differential geometry, a connection on a fibred manifold is a mathematical structure that allows one to compare and analyze the tangent spaces of the fibers of the manifold, where each fiber can be thought of as a submanifold of the total manifold. Connections are critical for defining concepts such as parallel transport, curvature, and differentiation of sections of vector bundles.
In the context of differential geometry and algebraic topology, a **connection** on a principal bundle is a mathematical structure that allows one to define and work with notions of parallel transport and differentiability on the bundle. A principal bundle is a mathematical object that consists of a total space \( P \), a base space \( M \), and a group \( G \) (the structure group) acting freely and transitively on the fibers of the bundle.
Costa's minimal surface is a notable example of a non-embedded minimal surface in three-dimensional space, discovered by the mathematician Hugo Ferreira Costa in 1982. It provides an important counterexample to the general intuition about minimal surfaces, particularly because it exhibits a complex topology. Here are some key features of Costa's minimal surface: 1. **Topological Structure**: Costa's surface is homeomorphic to a torus (it has the same basic shape as a donut).
A Darboux frame, often referred to in differential geometry, is a specific orthonormal frame associated with a surface in three-dimensional Euclidean space. It provides a systematic way to describe the local geometric properties of a surface at a given point. For a surface parametrized by a smooth map, the Darboux frame consists of three orthonormal vectors: 1. **Tangent vector (T)**: This is the unit tangent vector to the curve obtained by fixing one parameter (e.
The First Fundamental Form is a mathematical concept in differential geometry, which provides a way to measure distances and angles on a surface. It essentially encodes the geometric properties of a surface in terms of its intrinsic metrics. For a surface described by a parametric representation, the First Fundamental Form can be constructed from the parameters of that representation.
The Hilbert scheme is an important concept in algebraic geometry that parametrizes subschemes of a given projective variety (or more generally, an algebraic scheme) in a systematic way. More precisely, for a projective variety \( X \), the Hilbert scheme \( \text{Hilb}^n(X) \) is a scheme that parametrizes all closed subschemes of \( X \) with a fixed length \( n \).
A Hyperkähler manifold is a special type of Riemannian manifold that has a rich geometric structure. It is characterized by several key properties: 1. **Riemannian Manifold**: A Hyperkähler manifold is a Riemannian manifold, meaning it is equipped with a Riemannian metric that allows the measurement of distances and angles. 2. **Complex Structure**: It possesses a complex structure, which means that it can be viewed as a complex manifold.
The Lebrun manifold, also known as the Lebrun-Simpson manifold, is an important example in the study of Riemannian geometry and in the context of \(4\)-manifolds. It is a complex manifold that can be described as a Kähler surface. Specifically, it is notable for being a non-Kähler symplectic manifold, and it can be constructed as a particular type of complex algebraic surface.
A Lie algebroid is a mathematical structure that generalizes the concepts of Lie algebras and tangent bundles in differential geometry. It arises in various fields such as Poisson geometry, the study of foliations, and in the theory of dynamical systems. Lie algebroids provide a way to describe the infinitesimal symmetry of a manifold in a coherent algebraic framework.
Lu Ji (also known by his courtesy name Shiheng) was a notable figure from the late Eastern Han dynasty in China, renowned for his accomplishments as a poet and essayist. He is best known for his work "Wenjing" (文景), which emphasizes the importance of literature and the art of writing. His writings contributed significantly to Chinese literary tradition, showcasing his mastery of language and his ability to weave intricate thoughts into cohesive narratives.
Stand-up comedy is a comedic performance style where a comedian delivers a series of humorous anecdotes, observations, and one-liners in front of a live audience. The comedian typically stands on stage, hence the name "stand-up," and often engages directly with the audience to enhance the performance. Stand-up routines can cover a wide range of topics, including personal experiences, social issues, cultural observations, and everyday life.
Congressional Debate is a form of competitive debate where participants simulate the legislative process of the United States Congress. It involves students representing members of Congress, proposing and debating legislation, and discussing various resolutions. This type of debate is typically held in a formal setting, such as a conference or tournament, and follows rules similar to those of actual congressional procedures. Key elements of Congressional Debate include: 1. **Legislation**: Competitors are provided with bills and resolutions, which they must debate.
Satire is a genre of literature, film, and other forms of art that uses humor, irony, exaggeration, or ridicule to criticize or mock societal norms, institutions, individuals, or moral values. The primary aim of satire is often to provoke thought, entertain, or persuade audiences by highlighting flaws and absurdities in certain subjects.
Pop culture fiction refers to a genre of writing that integrates elements from popular culture—such as movies, television shows, music, fashion, social media, and internet trends—into its narratives. This genre often reflects and critiques contemporary societal norms and trends, capturing the spirit of the times. Pop culture fiction can take various forms, including novels, short stories, graphic novels, and even fan fiction.
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





