A **vector space** (also called a linear space) is a fundamental concept in linear algebra. It is an algebraic structure formed by a set of vectors, which can be added together and multiplied by scalars (real numbers, complex numbers, or more generally, elements from a field). Here are the key components and properties of vector spaces: ### Definitions 1. **Vectors**: Elements of the vector space.
The dual norm is a concept from functional analysis, particularly in the context of normed vector spaces. It extends the idea of a norm from a vector space to its dual space, which consists of all continuous linear functionals on that vector space.
An elementary matrix is a special type of matrix that results from performing a single elementary row operation on an identity matrix. Elementary matrices are useful in linear algebra, particularly in the context of solving systems of linear equations, performing Gaussian elimination, and understanding matrix inverses. There are three types of elementary row operations, each corresponding to a type of elementary matrix: 1. **Row Switching**: Swapping two rows of a matrix.
Fredholm's theorem is a result in the field of functional analysis, named after the Swedish mathematician Ivar Fredholm. It characterizes bounded linear operators on a Banach space (or a Hilbert space) in terms of the properties of their kernels, images, and the existence of continuous inverses. The theorem is primarily concerned with the properties of compact operators, which are operators that map bounded sets to relatively compact sets.
The Gram–Schmidt process is an algorithm used in linear algebra to orthogonalize a set of vectors in an inner product space, most commonly in Euclidean space. The primary goal of this process is to take a finite, linearly independent set of vectors and transform it into an orthogonal (or orthonormal) set of vectors, which are mutually perpendicular to one another or normalized to have unit length.
Matrix addition is a fundamental operation in linear algebra where two matrices of the same dimensions are added together element-wise. This means that corresponding entries in the two matrices are summed to produce a new matrix.
Weyr canonical form is a representation of a matrix that displays its structure in a standardized way, similar to Jordan canonical form, but with some differences. It specifically relates to the eigenvalues and the generalized eigenvectors of a matrix, particularly in the context of linear algebra. In the Weyr canonical form, the matrix is represented in a way that organizes the eigenvalues and their corresponding generalized eigenvectors into blocks.
The Nullspace Property (NSP) is a concept in the field of convex optimization, particularly in relation to the formulation of certain convex problems, such as basis pursuit and sparse representation. It is closely associated with matrices and their structure in terms of representing linear systems.
In mathematics, particularly in the fields of geometry and topology, an "orthant" refers to a generalization of quadrants in higher-dimensional spaces. Specifically, it denotes a portion of a Cartesian coordinate system, defined by the signs of the coordinates. For example, in a two-dimensional space (2D), the space is divided into four quadrants based on the signs of the x and y coordinates.
Peetre's inequality is a result in the field of functional analysis, particularly concerning the properties of certain function spaces and operators. Specifically, it pertains to the boundedness of certain linear operators between different functional spaces, such as Sobolev spaces or spaces of continuous functions.
In mathematics, "reduction" refers to the process of simplifying a problem or expression to make it easier to analyze or solve. The term can take on several specific meanings depending on the context: 1. **Algebraic Reduction**: This involves simplifying algebraic expressions or equations. For example, reducing an equation to its simplest form or factoring an expression. 2. **Reduction of Fractions**: This is the process of simplifying a fraction to its lowest terms.
The Schur complement is a concept in linear algebra that arises when dealing with block matrices. Given a partitioned matrix, the Schur complement provides a way to express one part of the matrix in terms of the other parts.
The term "spread" of a matrix can refer to different concepts depending on the context in which it is used. However, it doesn't have a universally accepted mathematical definition like terms such as "rank" or "dimension." Here are a couple of interpretations that might fit: 1. **Spread of Data in Statistics**: In the context of statistical analysis or data science, the "spread" of a matrix could refer to the variability or dispersion of the data it represents.
In linear algebra, the term "standard basis" typically refers to a set of basis vectors that provide a simple and intuitive way to understand vector spaces. The standard basis differs based on the context, usually depending on whether the vector space is defined over the real numbers \( \mathbb{R}^n \) or the complex numbers \( \mathbb{C}^n \).
The Stokes operator is a mathematical operator that arises in the study of fluid dynamics and the Navier-Stokes equations, which describe the motion of viscous fluid substances. The Stokes operator specifically relates to the study of the stationary Stokes equations, which can be viewed as a linear approximation of the Navier-Stokes equations for incompressible flows at low Reynolds numbers (where inertial forces are negligible compared to viscous forces).

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