Filtered category
The term "filtered category" can refer to various contexts, depending on the field in which it is used. Here are a few interpretations: 1. **E-commerce and Retail:** In the context of online shopping, a "filtered category" might refer to a selection of products that have been narrowed down based on specific criteria or filters, such as price range, brand, size, color, or other attributes. This allows customers to find products that meet their specific needs more easily.
Finitely generated object
In the context of algebra, a **finitely generated object** is an object that can be represented as a finite combination or structure generated by a finite set of elements. The specific definition can vary depending on the mathematical structure being discussed.
Freyd cover
A Freyd cover is a concept from category theory, particularly in the context of toposes and categorical logic. It refers to a particular type of covering that relates to the notion of a "Grothendieck universe" or a "set-like" behavior in certain categorical settings.
Fusion category
A fusion category is a mathematical structure from the field of category theory, specifically related to the study of categories that appear in the context of quantum physics and representation theory. In more detail, a fusion category is a special kind of monoidal category that has the following properties: 1. **Finite Dimensionality**: Fusion categories are typically finite-dimensional, meaning that the objects and morphisms can be described in a finite way.
Gamma-object
A Gamma-object is a concept from category theory, specifically in the context of homotopy theory and higher category theory. In this framework, a Gamma-object typically refers to a certain kind of structured object that captures the idea of "homotopy types" in a categorical sense. In simpler terms, a Gamma-object can be understood as a way to organize and study spaces and their maps in a more abstract environment than traditional topology.
Generator (category theory)
In category theory, a **generator** is a type of object that intuitively serves to "generate" other objects and morphisms in a given category.
Giraud subcategory
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.
Globular set
A globular set, also known as a globular space, is a concept from category theory and specifically from the field of higher dimensional algebra. It is a generalization of the notion of a topological space and is particularly useful in the study of homotopy theory and higher categories. In more detail, a globular set consists of a collection of "globes," which are objects that can be thought of as higher-dimensional analogs of points.
Glossary of category theory
A glossary of category theory includes definitions and explanations of fundamental concepts and terms used in the field. Here are some of the key terms: 1. **Category**: A collection of objects and morphisms (arrows) between those objects that satisfy certain properties. A category consists of objects, morphisms, a compositional law, and identity morphisms. 2. **Object**: The entities within a category. Each category contains a collection of objects.
Graded category
The term "graded category" can refer to different concepts depending on the context in which it is used, including mathematics, education, and assessment. Here are a few interpretations: 1. **In Mathematics (Category Theory)**: A graded category is a category where the morphisms (arrows) can be assigned a "grade" or degree, often represented by integers.
Grothendieck's Galois theory
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.
Grothendieck's relative point of view is a foundational concept that emerged from his work in algebraic geometry, particularly in the development of schemes and the theory of toposes. This perspective emphasizes the importance of understanding mathematical objects not just in isolation, but in relation to one another within a broader context.
Grothendieck category
A Grothendieck category is a specific type of category in the field of algebraic geometry and homological algebra, named after the mathematician Alexander Grothendieck. Grothendieck categories provide a framework for studying sheaves and derived categories, among other objects.
Grothendieck construction
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.
Grothendieck universe
A Grothendieck universe is a concept in set theory used primarily in category theory and algebraic geometry, named after the mathematician Alexander Grothendieck. It provides a way to work with large sets while avoiding certain foundational issues, like those that arise from Russell's paradox. The concept facilitates the rigorous treatment of categories and functors.
Groupoid object
In category theory, a **groupoid object** is a generalization of the concept of a group to the context of a category. A groupoid is essentially a category where every morphism is invertible. In the context of groupoid objects, we can think about them in terms of a base category and how they relate to group-like structures within that category.
Hylomorphism (computer science)
Hylomorphism is a concept derived from philosophy, specifically from Aristotle's metaphysics, but it has been adapted and utilized in computer science, particularly in the context of functional programming and type theory. In this context, hylomorphism refers to a specific kind of recursive data structure or computation.
Image (category theory)
In category theory, the **image** of a morphism can refer to a certain kind of idea that generalizes the concept of the image of a function in set theory. However, the exact definition and properties of the image can vary based on the context and the specific category in discussion.
Indexed category
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.
Indiscrete category
An **indiscrete category** is a simple type of category in category theory, which is a branch of mathematics that deals with mathematical structures and their relationships. Specifically, an indiscrete category consists of a single object and a single morphism (or arrow), which is the identity morphism for that object. Here's a breakdown of the key components: 1. **Objects**: An indiscrete category has exactly one object, which can be denoted as \( A \).