Homotopy is a concept in topology, a branch of mathematics that studies the properties and structures of spaces that are preserved under continuous transformations. More specifically, homotopy provides a way to classify continuous functions between topological spaces based on their ability to be deformed into one another.
Homotopy groups of spheres are a fundamental topic in algebraic topology that encapsulate information about the topology of higher-dimensional spheres. More formally, the \(n\)-th homotopy group of the \(n\)-dimensional sphere \(S^n\), denoted \(\pi_n(S^n)\), is defined as the set of homotopy classes of based continuous maps from the \(n\)-dimensional sphere \(S^n\) to itself.
Hugh of Saint Victor (circa 1096 – 1141) was a prominent medieval scholar, theologian, and philosopher, associated with the Benedictine monastery of Saint Victor in Paris. He is best known for his contributions to Christian mysticism, theology, and the educational theories of the period. Hugh's works emphasize the importance of inner spiritual experience and the pursuit of knowledge, blending faith with reason.
The Hunter Fracture Zone is a significant geological feature found in the oceanic crust. It is classified as a fracture zone, which is typically characterized by a series of faults occurring in the ocean floor that are the result of tectonic activity. Fracture zones are often associated with transform faults, where tectonic plates slide past each other horizontally. The Hunter Fracture Zone is located in the southwestern Pacific Ocean, near the boundary between the Pacific Plate and other surrounding plates.
HX-63 is a type of lithium-ion battery developed by the Chinese company Hunan Jintai Technology Co., Ltd. Primarily, this battery is used in various applications, including electric vehicles, energy storage systems, and consumer electronics. The HX-63 battery series may feature characteristics such as high energy density, long cycle life, and fast charging capabilities, making it suitable for a range of industrial and commercial uses.
Hydraulic fill is a construction material used primarily in civil engineering and construction projects, particularly for creating foundations, embankments, and reclaiming land. It consists of sediments, such as sand, silt, clay, or a combination of these materials, which are mixed with water to create a slurry. This slurry is then pumped into the desired area, where the water is subsequently allowed to drain or evaporate, leaving behind the solid materials.
Hydraulic laboratories are specialized facilities designed for testing and researching fluid mechanics and hydraulic engineering concepts. They are primarily used to study the behavior of fluids (liquids and gases) in various conditions and applications. These laboratories often include physical models of hydraulic structures, equipment to measure fluid flow, and tools to analyze the impact of various design parameters.
A hydraulic power network, also known as a hydraulic power system or hydraulic network, is a system that utilizes pressurized fluids to transmit power and perform work. These networks are typically used in various applications, including industrial machinery, construction equipment, and transportation systems. Here are some key components and principles associated with hydraulic power networks: ### Key Components: 1. **Pump**: Converts mechanical energy into hydraulic energy by moving fluid through the system under pressure.
Hydrogen embrittlement is a phenomenon in which metals, particularly high-strength steels and some alloys, become fragile and susceptible to fracture when exposed to hydrogen. This occurs as hydrogen atoms diffuse into the metal and accumulate at certain sites within the material, leading to a reduction in ductility and toughness. ### Mechanisms of Hydrogen Embrittlement: 1. **Hydrogen Absorption**: Hydrogen can be introduced into metals through various processes, including electroplating, welding, and corrosion.
Hydrology is the scientific study of water in the environment. It encompasses the distribution, movement, and properties of water in the Earth's atmosphere and on its surface, as well as underground. Hydrology involves understanding the hydrological cycle, which includes processes such as precipitation, evaporation, transpiration, infiltration, runoff, and storage of water in various forms like rivers, lakes, glaciers, and aquifers.
Hypercovering typically refers to a concept in topology and algebraic geometry that involves certain types of coverings related to sheaves, schemes, or topological spaces. In general, a hypercover is a tool used to construct derived functors or to study the properties of spaces in a more refined manner. In particular, in the context of sheaf theory, a hypercover is a type of covering that allows for 'higher' covering conditions.
Hypersociability refers to a heightened tendency to engage socially with others, often characterized by an intense desire for social interaction and a high level of sociability. Individuals who exhibit hypersociability may seek out social situations frequently, feel energized by being around others, and have difficulty spending time alone. This trait can manifest in various ways, such as being talkative, outgoing, and showing enthusiasm in social contexts.
A hypervalent molecule is one that has more than four bonds associated with a central atom, which typically involves elements from the third period or higher of the periodic table. In traditional valence bond theory, atoms like carbon (which is in the second period) are expected to form a maximum of four covalent bonds due to the tetravalent nature of carbon.
Ian S. E. Carmichael is a notable figure in the field of psychology, notably recognized for his contributions to research, especially in the areas of neuropsychology and cognitive assessment. However, without specific context, it's difficult to provide detailed information about him. If you have a particular area of interest or a specific inquiry regarding Ian S. E.
The ICL Distributed Array Processor (DAP) is a parallel processing computer developed by International Computers Limited (ICL) in the 1970s. It was designed primarily for scientific and engineering applications that require high-performance numerical computation. The DAP employs a unique architecture that allows it to perform operations on large datasets simultaneously, making it well-suited for tasks such as image processing, simulations, and complex mathematical problems.
The Intra-Americas Sea is a body of water located between the eastern coast of Central America and the western coast of the Caribbean Islands. It essentially connects the Caribbean Sea to the Atlantic Ocean, playing a crucial role in maritime navigation and regional climate patterns. The sea is bounded by various countries, including parts of Mexico, Belize, Guatemala, Honduras, Cuba, Jamaica, and the Bahamas.
Isuzu is a Japanese automotive manufacturer known primarily for producing commercial vehicles, including trucks and buses, as well as diesel engines. Founded in 1916, Isuzu has a long history in the automotive industry and has been involved in various partnerships and collaborations over the years. It is recognized for its expertise in diesel technology and has developed a strong reputation for building durable and reliable vehicles.
Ioana Dumitriu is a name that could refer to various individuals, but without specific context, it's hard to determine which person you might be referring to.
The term "isotypic component" often refers to a class or group of structures that share similar characteristics or classifications due to their common features. In different contexts, it can have different meanings, particularly in the fields of science, such as biology, chemistry, and materials science. 1. **In Biology:** In immunology, isotypes are different classes of antibodies (immunoglobulins) that have distinct functions and properties.
An Idoneal number is a positive integer \( n \) such that the equation \( x^2 - n y^2 = 1 \) has a solution in integers \( (x, y) \). This is a specific case of Pell's equation, which is generally of the form \( x^2 - D y^2 = 1 \) for some positive integer \( D \).

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