Fibered manifold
A fibered manifold is a type of manifold that is structured in such a way that it can be viewed as a "fiber bundle" over another manifold. More formally, a fibered manifold can be described in terms of a fibration, which is a particular kind of mapping between manifolds. To clarify, let’s break down the concept: 1. **Base Manifold**: A manifold \( B \) that serves as the "base" space for the fibration.
First fundamental form
The First Fundamental Form is a mathematical concept in differential geometry, which provides a way to measure distances and angles on a surface. It essentially encodes the geometric properties of a surface in terms of its intrinsic metrics. For a surface described by a parametric representation, the First Fundamental Form can be constructed from the parameters of that representation.
Frenet–Serret formulas
The Frenet–Serret formulas are a set of differential equations that describe the intrinsic geometry of a space curve in three-dimensional space. They provide a way to relate the curvature and torsion of a curve to the behavior of its tangent vector, normal vector, and binormal vector. The formulas are fundamental in the study of curves in differential geometry and are named after the mathematicians Jean Frédéric Frenet and Joseph Alain Serret.
G-structure on a manifold
In differential geometry, a \( G \)-structure on a manifold is a mathematical framework that generalizes the structure of a manifold by introducing additional geometric or algebraic properties. More specifically, a \( G \)-structure allows you to define a way to "view" or "furnish" the manifold with additional structure that can be treated similarly to how one treats vector spaces or tangent spaces.
Third fundamental form
The third fundamental form is a concept from differential geometry, particularly in the study of surfaces within three-dimensional Euclidean space (or higher-dimensional spaces). It is related to the intrinsic and extrinsic properties of surfaces. In the context of a surface \( S \) in three-dimensional Euclidean space, the first and second fundamental forms are well-known constructs used to describe the metric properties of the surface. These forms give insights into lengths, angles, and curvatures.
Torsion of a curve
Torsion is a measure of how a curve twists out of the plane formed by its tangent and normal vectors. In mathematical terms, torsion is defined for space curves, which are curves that exist in three-dimensional space.
Upper half-plane
The upper half-plane generally refers to a specific region in the complex plane. In complex analysis, it is defined as the set of all complex numbers whose imaginary part is positive.
The Gelfand–Naimark–Segal (GNS) construction is a fundamental technique in functional analysis and mathematical physics, particularly in the field of operator algebras and quantum mechanics. It provides a way to construct a representation of a *-algebra from a positive linear functional defined on that algebra.
Bounded mean oscillation
Bounded Mean Oscillation (BMO) is a function space used in the field of harmonic analysis and is particularly important in the study of partial differential equations, complex analysis, and real analysis. A function \( f \) defined on a domain (often \( \mathbb{R}^n \)) is said to belong to the BMO space if its mean oscillation over all balls (or spheres) in the domain is bounded.
Annie Jump Cannon
Annie Jump Cannon (1863–1941) was an American astronomer known for her significant contributions to the field of stellar classification. She is best known for developing the Harvard Classification Scheme, which categorizes stars based on their temperatures and spectral types. This system uses letters (O, B, A, F, G, K, M) to classify stars, with O being the hottest and M being the coolest.
The Hawaiian–Emperor seamount chain is a series of volcanoes and seamounts that extends from the Hawaiian Islands northwestward to the Aleutian Trench, showcasing some of the most active and well-studied volcanoes in the world. Here’s a list of the main volcanoes within this chain: ### Hawaiian Islands 1.
Eric Scerri
Eric Scerri is a philosopher of science and a chemist known for his work on the philosophy of chemistry and the history of the periodic table. He is particularly recognized for his research on the foundations and development of the periodic table of elements, as well as the implications that this has for our understanding of chemical education and the nature of scientific theories. Scerri has authored several books and numerous articles addressing these topics, and he is involved in promoting the importance of chemistry in the broader context of science.
Gauss curvature flow
Gauss curvature flow is a geometric evolution equation that describes the behavior of a surface in terms of its curvature. Specifically, it is a variation of curvature flow that involves the Gaussian curvature of the surface. In mathematical terms, given a surface \( S \) in \( \mathbb{R}^3 \), the Gauss curvature \( K \) is a measure of how the surface bends at each point.
Gaussian curvature
Gaussian curvature is a measure of the intrinsic curvature of a surface at a given point. It is defined as the product of two principal curvatures at that point, which are the maximum and minimum curvatures of the surface in two perpendicular directions.
The "Glossary of Riemannian and Metric Geometry" typically refers to a collection of terms and definitions commonly used in the fields of Riemannian geometry and metric geometry. These fields study the properties of spaces that are equipped with a notion of distance and curvature.
Grassmannian
The Grassmannian is a fundamental concept in the field of mathematics, particularly in geometry and linear algebra. More formally, the Grassmannian \( \text{Gr}(k, n) \) is a space that parameterizes all \( k \)-dimensional linear subspaces of an \( n \)-dimensional vector space. Here, \( k \) and \( n \) are non-negative integers with \( 0 \leq k \leq n \).
Gromov's inequality is a significant result in the field of differential geometry, particularly concerning the characteristics of complex projective spaces. It provides a lower bound for the volume of a k-dimensional holomorphic submanifold in a complex projective space in relation to the degree of the submanifold and the dimension of the projective space.
Tangential and normal components are terms used in the context of motion, especially in physics and engineering, to describe the ways in which a force or velocity can be decomposed in relation to a curved path. These components are particularly relevant when analyzing circular motion or any motion along a curved trajectory. ### Tangential Component - **Definition**: The tangential component refers to the part of a vector (like velocity or acceleration) that is parallel to the path of motion.
Contact geometry
Contact geometry is a branch of differential geometry that deals with contact manifolds, which are odd-dimensional manifolds equipped with a special kind of geometrical structure called a contact structure. This structure can be thought of as a geometric way of capturing certain properties of systems that exhibit a notion of "direction," and it is closely related to the study of dynamical systems and thermodynamics.
Scherrer equation
The Scherrer equation is a formula used in materials science and crystallography to estimate the size of crystalline domains in a material based on X-ray diffraction data. It provides a way to quantify the average size of coherently diffracting crystallites or grains within a sample. The equation is particularly useful for nanomaterials and thin films.