In mathematics, particularly in the context of linear algebra and functional analysis, a **linear form** (or linear functional) is a specific type of function that satisfies certain properties. Here are the main characteristics: 1. **Linear Transformation**: A linear form maps a vector from a vector space to a scalar.
In linear algebra, the nonnegative rank of a matrix is a measure of the smallest number of nonnegative rank-one matrices that can be summed to produce the original matrix. A rank-one matrix can be expressed as the outer product of two vectors.
A **quasinorm** is a generalization of the concept of a norm used in mathematical analysis, particularly in functional analysis and vector spaces. While a norm is a function that assigns a non-negative length or size to vectors (satisfying certain properties), a quasinorm relaxes some of these requirements.
The Restricted Isometry Property (RIP) is a concept from the field of compressed sensing and high-dimensional geometry. It describes a condition under which a linear transformation approximately preserves the distances between a limited number of vectors in a high-dimensional space.
A matrix difference equation is a mathematical equation that describes the relationship between a sequence of vectors or matrices at discrete time intervals. Specifically, it generalizes the concept of a scalar difference equation to the context of matrices or vectors.
The orientation of a vector bundle is a concept from differential geometry and algebraic topology that is related to the notion of orientability of the fibers of the bundle. A vector bundle \( E \) over a topological space \( X \) consists of a base space \( X \) and, for each point \( x \in X \), a vector space \( E_x \) attached to that point. The vector spaces are called the fibers of the bundle. ### Definition of Orientation 1.
The LINEAR (Lincoln Near-Earth Asteroid Research) project was a program designed to detect and track near-Earth objects, including asteroids and comets. Established in 1998, LINEAR made significant contributions to the discovery of various celestial objects.
The term "pairing" can refer to different concepts depending on the context. Here are a few common interpretations: 1. **Cooking and Beverages**: In culinary contexts, pairing often refers to the art of matching foods with beverages (like wine or beer) to enhance the overall dining experience. For example, red wine is commonly paired with red meat, while white wine is often paired with seafood.
In linear algebra, **projection** refers to the operation of mapping a vector onto a subspace. The result of this operation is the closest vector in the subspace to the original vector. This concept is crucial in various applications such as computer graphics, machine learning, and statistics. ### Key Concepts 1. **Subspace**: A subspace is a vector space that is part of a larger vector space.
In linear algebra, a **quotient space** is a way to construct a new vector space from an existing vector space by partitioning it into equivalence classes. This process can be thought of as "modding out" by a subspace, leading to a new space that captures certain properties while ignoring others.
Reducing subspace, often referred to in the context of dimensionality reduction in fields such as machine learning and statistics, typically refers to a lower-dimensional representation of data that retains the essential characteristics of the original high-dimensional space. The main goal of reducing subspaces is to simplify the data while preserving relevant information, allowing for more efficient computation, enhanced visualization, or improved performance on specific tasks.
The S-procedure is a mathematical technique used in convex optimization and control theory, specifically in the context of robust control and system stability analysis. It provides a way to transform certain types of inequalities involving quadratic forms into conditions that can be expressed in terms of linear matrix inequalities (LMIs).
Singular Value Decomposition (SVD) is a mathematical technique in linear algebra used to factorize a matrix into three other matrices. It is particularly useful for analyzing and reducing the dimensionality of data, solving linear equations, and performing principal component analysis.
Spinors are mathematical objects used in physics and mathematics, particularly in the context of quantum mechanics and the theory of relativity. In three dimensions, spinors can be understood as a generalization of the notion of vectors and can be associated with the representation of the rotation group, specifically the special orthogonal group SO(3). ### Definition and Representation In three-dimensional space, spinors are typically expressed in relation to the group of rotations SO(3).
Split-complex numbers, also known as hyperbolic numbers or null numbers, are a type of number that extends the real numbers similarly to how complex numbers extend them. They are defined as numbers of the form: \[ z = x + yj \] where \( x \) and \( y \) are real numbers, and \( j \) is a unit with the property that \( j^2 = 1 \).
The term "star domain" can refer to different concepts depending on the context. Here are a few interpretations: 1. **Astronomy and Astrophysics**: In the context of stars and celestial bodies, a "star domain" could refer to a region of space that includes a group of stars or star systems. This could pertain to a section of a galaxy or a cluster of stars that share certain characteristics or are gravitationally bound.
Near-parabolic comets are comets whose orbits are close to parabolic, indicating that they are on the verge of escaping the Sun's gravitational influence. These comets typically have orbital eccentricities close to 1, which means their paths are elongated but not quite sufficient to be classified as hyperbolic (eccentricity greater than 1).
A Z-order curve, also known as a Z-ordering or Morton order, is a spatial filling curve that is used to map multi-dimensional data (like two-dimensional coordinates) into one-dimensional data while preserving the spatial locality of the points. This means that points that are close together in the multi-dimensional space will remain close together in the one-dimensional representation. The Z-ordering works by interleaving the binary representations of the coordinates of the points.
Zech's logarithm, denoted as \( z \), is a mathematical construct used primarily in the field of finite fields and combinatorial structures, such as in coding theory and cryptography. It arises in relation to the concepts of logarithms in finite fields, specifically in the context of operations involving powers of elements in these fields.

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