In category theory, a **cone** is a concept that originates from the idea of a collection of objects that map to a common object in a diagram. More formally, if you have a diagram \( D \) in a category \( \mathcal{C} \), a cone over that diagram consists of: 1. An object \( C \) in \( \mathcal{C} \), often referred to as the "apex" of the cone.
In category theory, a "cosmos" is a concept that extends the idea of a category to a more general framework, allowing for the study of "categories of categories" and related structures. Specifically, a cosmos is a category that is enriched over some universe of sets or types, which allows for a more flexible approach to discussing categories and their properties.
In mathematics, particularly in category theory, a **distributive category** is a type of category that generalizes certain properties found in specialized algebraic structures, such as distributive lattices in order theory. While the term is not as widely recognized or standardized as others in category theory, it typically refers to a structure that satisfies specific distributive laws concerning the composition of morphisms and the behavior of products and coproducts.
Enriched category by Wikipedia Bot 0
The term "enriched category" typically arises in the context of category theory, a branch of mathematics that deals with abstract structures and relationships between them. In general, a category consists of objects and morphisms (arrows) that represent relationships between those objects. An **enriched category** expands this concept by allowing the hom-sets (the sets of morphisms between objects) to take values in a more general structure than merely sets.
F-algebra by Wikipedia Bot 0
In mathematics, particularly in the fields of category theory and algebra, an **F-algebra** is a structure that is defined in relation to a functor \( F \) from a category to itself.
In category theory, a **generator** is a type of object that intuitively serves to "generate" other objects and morphisms in a given category.
The concept of a Giraud subcategory arises in the context of category theory, particularly in the study of suitable subcategories of a given category. Giraud subcategories are named after the mathematician Jean Giraud, and they are important in the study of sheaf theory and topos theory. A Giraud subcategory is typically defined as a full subcategory of a topos (or a category with certain desirable properties) that retains the essential features of "nice" categories.
Grothendieck's Galois theory is an advanced branch of algebraic geometry and algebraic number theory that generalizes classical Galois theory. Introduced by Alexander Grothendieck in the 1960s, it focuses on the relationship between fields, algebraic varieties, and their coverings, especially in the context of schemes.
The Grothendieck construction is a method in category theory and algebraic topology that allows for the construction of a new category from a functor. Specifically, it is used to "glue together" objects from a family of categories indexed by another category through a functor.
Indexed category by Wikipedia Bot 0
An **indexed category** is a generalization of the concept of categories in category theory, which allows for a more structured way to organize objects and morphisms. In traditional category theory, a category consists of a collection of objects and morphisms (arrows) between them. An indexed category extends this by organizing a category according to some indexing set or category, which provides a way to manage multiple copies of a particular structure.
In category theory, an **isomorphism-closed subcategory** is a subcategory of a given category that is closed under isomorphisms. This means that if an object is in the subcategory, then all objects isomorphic to it are also included in the subcategory. To elaborate further, let \( \mathcal{C} \) be a category and let \( \mathcal{D} \) be a subcategory of \( \mathcal{C} \).
A **Krull–Schmidt category** is a concept in category theory, particularly in the study of additive categories and their decomposition properties. It is named after mathematicians Wolfgang Krull and Walter Schmidt. In a Krull–Schmidt category, every object can be decomposed into indecomposable objects in a manner that is unique up to isomorphism and ordering.
In category theory, presheaves are a way to assign sets (or more generally, objects in a category) to the open sets of a topological space (or objects in a category that have a similar structure).
In category theory, localization is a process that allows you to formally "invert" certain morphisms in a category, essentially creating a new category in which these morphisms are treated as isomorphisms. This process is analogous to inverting elements in a mathematical structure (like fractions in the integers to form the rationals) and is crucial for many constructions and applications in both abstract mathematics and applied areas.
Opetope by Wikipedia Bot 0
As of my last update in October 2023, "Opetope" does not refer to any widely recognized concept, entity, or product in common knowledge, technology, or culture. It's possible that it could be a specific term, name, or concept that emerged after that date, or it could be niche or specific to a certain field not covered in mainstream sources.
In category theory, the concept of a permutation category can refer to a specific kind of category that captures the structure and properties of permutations. A permutation is a rearrangement of a finite set of elements, and permutation categories can be used to study transformations and symmetries in various mathematical contexts. One common way to formalize the permutation category is through the **category of finite sets and bijections**.
Pointless topology, also known as "point-free topology," is a branch of topology that focuses on the study of topological structures without reference to points. Instead of using points as the fundamental building blocks, it emphasizes the relationships and structures formed by open sets, closed sets, or more general constructs such as locales or spaces. In typical point-set topology, a topological space is defined as a set of points along with a collection of open sets that satisfy certain axioms.
Simplicial localization is a concept from algebraic topology and category theory that is concerned with the process of localizing simplicial sets or simplicial categories. The process is usually aimed at constructing a new simplicial set that reflects the homotopical or categorical properties of the original set while allowing one to "invert" certain morphisms or objects. ### Background Concepts 1. **Simplicial Sets:** A simplicial set is a combinatorial structure that encodes topological information.
KCNJ10 by Wikipedia Bot 0
KCNJ10 is a gene that encodes a member of the potassium ion channel family, specifically an inward-rectifier potassium channel. The protein produced by this gene is involved in potassium ion transport across cell membranes, which is crucial for various physiological processes, including maintaining the resting membrane potential of cells, regulating cellular excitability, and influencing the secretion of hormones and neurotransmitters.
In mathematics, a "sketch" typically refers to a rough or informal outline of a mathematical concept, proof, or argument. It helps convey the main ideas without going into exhaustive detail. A sketch might include key steps, important definitions, or significant results, and can serve as a guide for further development into a full, rigorous presentation.

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