A **multiplicative group** is a mathematical structure consisting of a set equipped with a binary operation that satisfies certain properties. Specifically, a multiplicative group is a set \( G \) along with a binary operation (commonly denoted as multiplication) that has the following characteristics: 1. **Closure**: For any two elements \( a, b \in G \), the result of the operation \( a \cdot b \) is also in \( G \).
A Moufang polygon is a type of combinatorial structure that generalizes certain properties of projective planes and certain geometric configurations. More specifically, Moufang polygons can be viewed as a particular kind of building in the theory of buildings in geometric group theory, related closely to groups of Lie type and algebraic structures. A Moufang polygon can be defined as a finite, strongly regular combinatorial structure defined with respect to a set of vertices and certain incidence relations among them.
As of my last update in October 2023, "Monus" could refer to a few different things depending on the context. It may refer to: 1. **Monus (Currency)**: In some contexts, "Monus" might refer to a digital currency or token. It's essential to check specific cryptocurrency platforms or forums for the most recent developments in digital currencies.
A **monoid** is an algebraic structure that consists of a set equipped with a binary operation that satisfies two key properties: associativity and identity. More formally, a monoid is defined as a tuple \((M, \cdot, e)\), where: 1. **Set \(M\)**: This is a non-empty set of elements.
A **monogenic semigroup** is a particular type of algebraic structure in the field of abstract algebra. Specifically, a semigroup is a set equipped with an associative binary operation. In the case of a monogenic semigroup, there is a specific defining feature: the semigroup is generated by a single element.
In mathematics, a **module** is a generalization of the concept of a vector space. While vector spaces are defined over a field, modules allow for the scalars to be elements of a more general algebraic structure called a ring.
A matrix ring is a specific type of ring constructed from matrices over a ring. Formally, if \( R \) is a ring (which can be, for example, a field or another ring), then the set of \( n \times n \) matrices with entries from \( R \) forms a ring, denoted by \( M_n(R) \). The operations defined in this ring are matrix addition and matrix multiplication.
A "matrix field" can refer to different concepts depending on the context in which it is used. Here are a few interpretations based on various disciplines: 1. **Mathematics and Linear Algebra**: In mathematics, particularly in linear algebra, a matrix field often refers to an array of numbers (or functions) organized in rows and columns that can represent linear transformations or systems of equations. However, “matrix field” might not be a standard term, as fields themselves are mathematical structures.
In the field of algebra, a **magma** is a very basic algebraic structure. It is defined as a set \( M \) equipped with a binary operation \( * \) that combines two elements of the set to produce another element in the set. Formally, a magma is defined as follows: - A **magma** is a pair \( (M, *) \) where: - \( M \) is a non-empty set.
MV-algebra, or many-valued algebra, is a mathematical structure used in the study of many-valued logics, particularly those that generalize classical propositional logic. The concept was introduced in the context of Lukasiewicz logic, which allows for truth values beyond just "true" and "false.
Lindenbaum–Tarski algebra is a structure in mathematical logic and model theory that arises from the study of formal systems, particularly those dealing with propositional or predicate logic. It is named after the mathematicians Adolf Lindenbaum and Alfred Tarski, who contributed significantly to the foundations of mathematical logic. In essence, a Lindenbaum–Tarski algebra is a specific type of Boolean algebra that is constructed from the collection of all consistent sets of formulas in a given formal system.
In mathematics, particularly in order theory, a **lattice** is a specific type of algebraic structure that is a partially ordered set (poset) with unique least upper bounds (suprema or joins) and greatest lower bounds (infima or meets) for any two elements.
Kleene algebra is a mathematical structure used in theoretical computer science, formal language theory, and algebra. It is named after the mathematician Stephen Kleene, who made significant contributions to the foundations of automata theory and formal languages. Kleene algebra consists of a set equipped with certain operations and axioms that support reasoning about the properties of regular languages and automata.
The Kasch ring is a geometric structure used in the field of differential geometry and topology, particularly in relation to the study of manifolds and their properties. Specifically, the Kasch ring is associated with the concept of the curvature of a Riemannian manifold, and it may also arise in the context of algebraic topology.
A Jónsson–Tarski algebra is a specific type of algebraic structure related to Boolean algebras and described by properties connected to the concept of free algebras. The notion is named after the mathematicians Bjarni Jónsson and Alfred Tarski, who made significant contributions to the fields of mathematical logic and algebra.
The term "J-structure" can refer to different concepts depending on the context in which it is used. Here are a few possible interpretations: 1. **Mathematics and Geometry**: In the context of mathematics, particularly in algebraic topology or manifold theory, J-structure can refer to a specific type of geometric or topological structure associated with a mathematical object. It might relate to an almost complex structure or a similar concept depending on the area of study.
An **inverse semigroup** is a specific type of algebraic structure that combines the properties of semigroups and the concept of invertibility of elements. A semigroup is an algebraic structure consisting of a set equipped with an associative binary operation, while an inverse semigroup has additional properties related to inverses.
Interior algebra is a branch of mathematics that deals with the study of certain algebraic structures that arise in the context of topology, particularly in relation to topological spaces and their properties. Its primary focus is on the algebraic operations defined on sets of open and closed sets in a topological space. In more detail, interior algebra typically involves concepts like: 1. **Interior and Closure**: The operations of taking the interior and closure of sets within a topological space.
An integral element is a term used in various fields, primarily in mathematics and abstract algebra, as well as in related contexts like computer science and physics. However, without a specific context, the meaning can vary. 1. **Mathematics/Abstract Algebra**: In ring theory, an integral element refers to an element of an integral domain (a type of commutative ring) that satisfies a monic polynomial equation with coefficients from that domain.
The integral closure of an ideal is a concept from commutative algebra and algebraic geometry that has to do with the properties of rings and ideals.

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 5. . 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.
  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