The Engel Group typically refers to a series of companies or divisions under the Engel brand, which is known for manufacturing injection molding machines and automation technology, primarily for the plastic processing industry. Engel is an international company based in Austria that provides solutions for various applications, including automotive, packaging, medical technology, and consumer goods.
A finitely generated group is a group \( G \) that can be generated by a finite set of elements. More formally, there exists a finite set of elements \( \{ g_1, g_2, \ldots, g_n \} \) in \( G \) such that every element \( g \in G \) can be expressed as a finite combination of these generators and their inverses.
Geometric group theory is a branch of mathematics that studies the connections between group theory and geometry, particularly through the lens of topology and geometric structures. It emerged in the late 20th century and has since developed into a rich area of research, incorporating ideas from various fields including algebra, topology, and geometry. Key concepts in geometric group theory include: 1. **Cayley Graphs**: These are graphical representations of groups that illustrate the group's structure.
The concept of a **Homeomorphism group** arises in the field of topology, which is the study of the properties of space that are preserved under continuous transformations. Let's break down what a homeomorphism is and then define the homeomorphism group. ### Homeomorphism A **homeomorphism** is a special type of function between two topological spaces.
The list of finite simple groups is a comprehensive classification of finite groups that cannot be decomposed into simpler groups. A finite simple group is defined as a nontrivial group whose only normal subgroups are the trivial subgroup and the group itself. Finite simple groups can be categorized into several families: 1. **Cyclic Groups of Prime Order**: These are groups of the form \( \mathbb{Z}/p\mathbb{Z} \) for a prime \( p \).
"Measurable acting group" does not appear to refer to a widely recognized term or concept in the fields of acting, performance, or any related discipline as of my last update in October 2023. It’s possible that it could refer to a specific group or project, perhaps one that incorporates methods of measuring performance or impact in acting.
The representation ring is an important concept in the field of algebra and representation theory, particularly in the study of groups and algebras. It is used to encode information about the representations of a given algebraic structure, such as a group, in a ring-theoretic framework.
In the context of group theory, a **retract** is a specific type of subgroup related to the notion of projection. To understand this concept, we first need to define a few key terms: 1. **Group**: A set equipped with an operation that satisfies four fundamental properties: closure, associativity, the identity element, and invertibility. 2. **Subgroup**: A subset of a group that itself forms a group under the operation of the larger group.
The Eilenberg–Ganea theorem is a fundamental result in algebraic topology, specifically in the theory of topological spaces and homotopy theory. Named after mathematicians Samuel Eilenberg and Tadeusz Ganea, the theorem concerns the relationship between the fundamental group of a space and its higher homotopy groups.
Kanimozhi is a Tamil name that can refer to a few different things: 1. **Kanimozhi Karunanidhi**: Most commonly, it refers to a prominent Indian politician and a member of the Dravida Munnetra Kazhagam (DMK) party in Tamil Nadu. She was born on January 5, 1968, and is the daughter of the late M. Karunanidhi, a former Chief Minister of Tamil Nadu.
A Tamari lattice is a combinatorial structure that arises in the study of certain types of parenthetical expressions, specifically in the context of binary trees and parenthesizations. It is named after the mathematician Tamari, who studied the ordering of different ways to fully parenthesize a sequence of variables.
Admissible representation is a concept that can refer to various contexts, such as mathematics, logic, and artificial intelligence. Generally, it pertains to a system of representing knowledge, information, or states in a way that adheres to specific criteria or constraints. For example: 1. **In Artificial Intelligence and Search Algorithms**: An admissible heuristic is one that never overestimates the cost to reach the goal from the current state.
Cellular algebra is a type of algebraic structure that arises in the context of representation theory, particularly in the study of coherent and modular representations of certain algebraic objects. It provides a framework for understanding the representation theory of groups, algebras, and related structures using a combinatorial approach.
The Chang number is a concept from the field of mathematics, specifically in topology and combinatorics. It is named after the mathematician Chao-Chih Chang. In more detail, the Chang number is a cardinal number that arises in the context of certain properties of functions and transformations, particularly in the study of large cardinals and their relationships to set theory.
The Gelfand–Graev representation is a specific type of representation associated with the theory of finite groups, particularly in the context of group algebras and representation theory. Named after I. M. Gelfand and M. I. Graev, this representation is a construction that arises in the study of group characters and modular representations.
The McKay graph is a type of graph used in the field of algebraic combinatorics, particularly in the study of group theory and representation theory. Specifically, it arises in the context of the representation theory of finite groups. For a given finite group \( G \), the McKay graph is constructed as follows: 1. **Vertices**: The vertices of the McKay graph correspond to the irreducible representations of the group \( G \).
Division algebra is a type of algebraic structure where division is possible, except by zero. More formally, a division algebra is a vector space over a field \( F \) equipped with a bilinear multiplication operation that satisfies the following conditions: 1. **Non-Associativity or Associativity**: In a general division algebra, multiplication can be either associative or non-associative. If it is associative, the algebra is called an associative division algebra.
The Ore extension, named after the mathematician Ole Johan Dahl Ore, is a concept in algebra that pertains to the extension of rings and modules. In particular, it is used to construct new rings from a given ring by adding new elements and defining new operations. The most common application of Ore extensions occurs in the context of noncommutative algebra, where it is used to form the Ore localization of a polynomial ring. This involves extending a ring by introducing new elements that satisfy specific relations concerning multiplication.
In the context of ring theory, a branch of abstract algebra, a **perfect ring** is a specific type of ring that has certain characteristics relating to its structure, particularly concerning ideals and their relations to other elements in the ring.

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