Ε-quadratic form by Wikipedia Bot 0
The term "E-quadratic form" appears to refer to a type of quadratic form characterized by a specific kind of structure or properties, particularly in the context of mathematics. While there isn't a universally recognized definition for "E-quadratic form" specifically, the term might relate to concepts in algebra, geometry, or particularly in number theory. In general, a **quadratic form** is a homogeneous polynomial of degree two in a number of variables.
Proxy bid by Wikipedia Bot 0
A proxy bid is a bidding method used primarily in auctions, where a bidder allows an auction house or a bidding platform to place bids on their behalf up to a specified maximum amount. The purpose of a proxy bid is to automate the bidding process and ensure that the bidder doesn't have to continuously monitor the auction or manually place each bid.
Turán's brick factory problem is a classic problem in combinatorial optimization, particularly in the field of graph theory. It is named after the Hungarian mathematician Paul Erdős and his colleague László Turán, who studied problems involving extremal graph theory. The problem can be described as follows: Imagine a brick factory that produces bricks of various colors.
Brauer group by Wikipedia Bot 0
The Brauer group is a fundamental concept in algebraic geometry and algebra, particularly in the study of central simple algebras. It encodes information about dividing algebras and Galois cohomology. In more precise terms, the Brauer group of a field \( K \), denoted \( \text{Br}(K) \), is defined as the group of equivalence classes of central simple algebras over \( K \) under the operation of tensor product.
The Lefschetz hyperplane theorem is a fundamental result in algebraic geometry and topology that relates the topology of a projective variety to that of its hyperplane sections. Specifically, it provides information about the cohomology groups of a projective variety and its hyperplane sections. To state the theorem more formally: Let \(X\) be a smooth projective variety of dimension \(n\) defined over an algebraically closed field.
The Kodaira vanishing theorem is a fundamental result in algebraic geometry, named after Kunihiko Kodaira. It provides important information about the cohomology of certain types of sheaves on smooth projective varieties. ### Statement of the Theorem In its classical form, the Kodaira vanishing theorem can be stated as follows: Let \( X \) be a smooth projective variety over the complex numbers, and let \( L \) be an ample line bundle on \( X \).
Topology of homogeneous spaces is a concept in mathematics that primarily arises in the field of differential geometry and algebraic topology. A **homogeneous space** is a type of space that looks "the same" at every point, meaning it can be acted upon transitively by a group of symmetries (often a Lie group).
Gerbe by Wikipedia Bot 0
The term "gerbe" can refer to multiple concepts depending on the context. Here are a few possible interpretations: 1. **In Agriculture**: A gerbe is a bundle of agricultural products, typically straw or grain, that is made into a sheaf for drying and storage. 2. **In Mathematics**: A gerbe is a concept from algebraic geometry and category theory.
Invertible sheaf by Wikipedia Bot 0
In algebraic geometry, an **invertible sheaf** (also known as a line sheaf) is a specific type of coherent sheaf that is locally isomorphic to the sheaf of sections of the structure sheaf of a variety.
Reflexive sheaf by Wikipedia Bot 0
In algebraic geometry and related fields, a **reflexive sheaf** is a specific type of sheaf that arises in the study of coherent sheaves and their properties on algebraic varieties or topological spaces. Reflexive sheaves are closely related to duality concepts and have implications in the study of singularities, birational geometry, and intersection theory.
In algebraic geometry, a **sheaf** is a mathematical structure that encodes local data that can be consistently patched together over a topological space. When we extend this concept to **algebraic stacks**, the notion of a sheaf plays a crucial role in the study of coherent structures on these more complex spaces.
The Focal Subgroup Theorem is a concept in the area of algebraic topology and group theory, particularly relating to finite group actions and their relationships to fixed point sets in topological spaces. In more detail, the Focal Subgroup Theorem often pertains to the study of groups acting on topological spaces and examines the interaction between the group action and the topology of the space.
Powerful p-group by Wikipedia Bot 0
A **powerful \( p \)-group** is a special type of \( p \)-group (a group where the order of every element is a power of a prime \( p \)) that satisfies certain conditions regarding its commutator structure.
Complex representation refers to the method of expressing mathematical or physical concepts using complex numbers, which are numbers that have both a real part and an imaginary part.
The Multiplicity-One Theorem is a concept in the field of algebraic geometry, particularly in the study of algebraic varieties and their singularities. It is often applied in the context of intersections of algebraic varieties, particularly in relation to issues involving the dimension and the multiplicity of points of intersection. In general terms, the Multiplicity-One Theorem states that if two varieties intersect transversely at a point, then the intersection at that point has multiplicity one.
In the context of group theory, the regular representation of a group provides a way to represent group elements as linear transformations on a vector space.
Tempered representations are a concept from the field of representation theory, particularly in the context of reductive groups over local fields. They are an important part of the harmonic analysis on groups and play a vital role in the study of automorphic forms and number theory. In more detail: 1. **Context**: Tempered representations arise in the study of the representations of reductive groups over a local field (like the p-adic numbers or the real numbers).
Cantor cube by Wikipedia Bot 0
The Cantor cube, often denoted as \(2^\omega\) or \([0, 1]^\omega\), is a product space that arises in topology and set theory. It can be understood in a few different ways: 1. **Composition**: The Cantor cube is defined as the countable infinite product of the discrete space \(\{0, 1\}\).
In the context of group theory, the concept of a **fully normalized subgroup** pertains to a subgroup that is maximal with respect to the property of being normal in a certain sense. Specifically, a subgroup \( H \) of a group \( G \) is said to be fully normalized if it is normal in every subgroup of \( G \) that contains it.
In the context of topological groups, the **direct sum** (often referred to as the **direct product**, especially in the category of groups) of a family of topological groups provides a way to combine these groups into a new topological group. The construction is analogous to that of the direct sum in vector spaces.

Pinned article: ourbigbook/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