Seshat is a collaborative research project that aims to create a comprehensive and systematic database of historical data for various societies across the globe and throughout history. Established to further the study of human social complexity, Seshat focuses on collecting, coding, and analyzing a wide array of social, cultural, and environmental variables. This information is utilized by researchers in fields such as anthropology, archaeology, history, and sociology to investigate patterns and trends in societal development, governance, economic systems, and more.
In mathematical analysis, a function is said to be of bounded variation on an interval if the total variation of the function over that interval is finite. Total variation gives a measure of the oscillation or fluctuation of the function values over the interval. ### Definition Let \( f: [a, b] \to \mathbb{R} \) be a real-valued function defined on the closed interval \([a, b]\).
The isoperimetric inequality is a fundamental result in mathematics, particularly in geometry and analysis. It relates the length of a closed curve (the perimeter) to the area it encloses. The classic formulation states that for a simple closed curve in the plane, the perimeter \( P \) and the area \( A \) are related by the inequality: \[ P^2 \geq 4\pi A, \] with equality holding if and only if the shape is a circle.
The "path of least resistance" is a phrase that describes the tendency of systems, individuals, or processes to follow the easiest or most straightforward path when confronted with obstacles or choices. This concept can be applied in various contexts, including physics, psychology, decision-making, and even social behavior. ### In Different Contexts: 1. **Physics**: In the context of electricity, for example, current will flow through the pathway that offers the least resistance.
Saint-Venant's theorem, named after the French engineer Adhémar Jean Claude Michel, Baron de Saint-Venant, is a fundamental principle in the field of mechanics, particularly in the study of elasticity and structural analysis. The theorem addresses how the effects of loads (or external forces) applied to a structure diminish with distance from the point of application.
Transversality is a concept in mathematics, particularly in differential topology and analysis, which describes a certain generic position of geometric objects such as manifolds, curves, or surfaces relative to each other. The idea helps generalize intersections and singularities of maps and manifolds. In a more formal sense, consider two manifolds (or submanifolds) \( M \) and \( N \) within a larger manifold \( P \).
The Clebsch–Gordan coefficients are numerical factors that arise in the study of angular momentum in quantum mechanics and in the theory of representations of groups, specifically the group \( SU(2) \) associated with rotations. They describe how to combine two angular momentum states into a total angular momentum state.
In quantum field theory (QFT), common integrals often refer to the integrals that arise in the calculation of physical quantities, such as propagators, correlation functions, and scattering amplitudes. These integrals commonly include both momentum space and position space integrals. Here are some of the most important types of integrals encountered frequently: 1. **Fourier Transforms:** The transition between position space and momentum space is performed via Fourier transforms.
The Degasperis–Procesi equation is a nonlinear partial differential equation that arises in the context of the study of shallow water waves and certain integrable systems. It can be viewed as a modification of the Korteweg-de Vries (KdV) equation and is notable for its role in mathematical physics, particularly in modeling waves and other phenomena.
Gauge theory is a type of field theory in which the Lagrangian (the mathematical function that describes the dynamics of the system) is invariant under certain local transformations, or "gauge transformations." These transformations can vary from point to point in spacetime and are foundational to our understanding of fundamental forces in physics, particularly in the framework of particle physics and the Standard Model. ### Key Concepts 1.
A holonomic basis is a concept in the field of differential geometry and the theory of differential equations, particularly in the study of differential forms and integrability. In a more specific context, a basis of a tangent space in a manifold is said to be holonomic if the basis vectors can be expressed in terms of a coordinate system. This means that the basis elements can be derived from the standard differential of the coordinates.
A Lyapunov vector is a mathematical concept used in the study of dynamical systems, particularly in the context of stability analysis and the behavior of differential equations. Lyapunov vectors are related to Lyapunov exponents, which measure the rate of separation of infinitesimally close trajectories of a dynamical system. When analyzing the stability of a fixed point or equilibrium of a dynamical system, Lyapunov exponents help quantify the growth or decay rates of perturbations around that point.
Multiple-scale analysis, also known as multiscale analysis, is a mathematical and analytical framework used to study phenomena that exhibit behavior on different spatial or temporal scales. This approach is particularly useful in various fields, including physics, engineering, biology, and applied mathematics, where systems show complex behaviors that cannot be properly understood by focusing solely on a single scale.
Transportation Science is an interdisciplinary field that focuses on the analysis, design, and optimization of transportation systems and their components. It encompasses various aspects of transportation, including infrastructure, vehicles, operations, logistics, and policy. The goal of Transportation Science is to improve the efficiency, safety, reliability, and sustainability of transportation systems while addressing issues like traffic congestion, environmental impacts, and public safety.
Quantitative psychologists are specialists within the field of psychology who focus on the development and application of statistical and mathematical methods to understand psychological phenomena. Their work encompasses a variety of tasks, including: 1. **Research Design:** They design experiments and studies that systematically test psychological theories and hypotheses. 2. **Data Analysis:** Quantitative psychologists utilize statistical techniques to analyze data collected from psychological research, helping to determine relationships, effects, and patterns.
A reasoning system is a computational framework or model designed to process information and draw conclusions based on a set of premises or rules. These systems are foundational in artificial intelligence (AI), logic, computer science, and knowledge representation, among other fields. Here are some key aspects of reasoning systems: 1. **Types of Reasoning**: - **Deductive Reasoning**: This involves deriving specific conclusions from general rules or premises. If the premises are true, the conclusions must also be true.
A computational problem refers to a task that can be formalized in terms of inputs, outputs, and a specific method or algorithm to transform the inputs into the outputs. In more technical terms, a computational problem consists of defining a set of instances, where each instance is associated with a specific input, and specifying the desired output for those inputs.
The Journal of Automata, Languages and Combinatorics (JALC) is a scholarly journal that focuses on research in the fields of automata theory, formal languages, and combinatorial methods in computer science and mathematics. It publishes original research articles, surveys, and papers that contribute to the understanding of the theoretical aspects of computation.
The Neighbour-sensing model refers to a conceptual framework or computational model utilized in various fields, including social sciences, biology, and computer science, to analyze interactions and relationships based on the presence and influence of neighboring entities. It can be applied in numerous contexts, but the specifics can vary depending on the discipline.
Quantum complexity theory is a branch of theoretical computer science that studies the complexity of problems within the framework of quantum computation. It explores how quantum algorithms can solve problems more efficiently than classical algorithms and seeks to classify problems based on their computational hardness in the quantum setting. Here are some key concepts and topics in quantum complexity theory: 1. **Quantum Computation Model**: Quantum complexity theory is grounded in the model of quantum computation, where computation is performed using quantum bits (qubits).

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