Eulerian numbers, denoted as \( E(n, k) \), are a set of integers that count the number of permutations of \( n \) elements in which exactly \( k \) elements appear in ascents. An ascent in a permutation is a position where the next element is larger than the current one.
The term "exponential factorial" is not widely used in standard mathematical literature. However, it typically refers to a function that grows extremely quickly, related to the factorial function. Depending on the context, it could imply different things. Here are a couple of interpretations: 1. **Factorial of a Factorial**: One way to interpret "exponential factorial" is to consider the factorial of a factorial, denoted as \( n!
The Golomb sequence is a non-decreasing integer sequence where each positive integer \( n \) appears exactly \( G(n) \) times in the sequence.
The Lambek–Moser theorem is a result in the field of mathematical logic and category theory, specifically concerning the structure of certain types of algebraic systems. It is often cited in the context of combinatory logic and the study of proof theories. In simple terms, the theorem provides conditions under which certain kinds of structures (like categories or algebraic theories) can represent a certain type of logic system.
A strobogrammatic number is a number that appears the same when rotated 180 degrees (or flipped upside down). This means that the individual digits in the number can be transformed into other digits (or themselves) when turned.
The Ménage problem is a classic problem in combinatorics that involves counting the number of ways to arrange couples such that no couple sits next to each other. Typically, the problem is stated with a specific number of couples, and the arrangements are considered around a circular table.
Einstein's Blackboard refers to a famous blackboard that was used by Albert Einstein during his time at the Institute for Advanced Study in Princeton, New Jersey. The blackboard gained notoriety because it was used by Einstein to jot down his thoughts, equations, and ideas related to his research in theoretical physics.
Cultural depictions of Albert Einstein span a wide range of media, including literature, film, television, music, and visual art. His image and persona have become iconic, often symbolizing genius and intellectual prowess. Here are some notable aspects of how Einstein has been portrayed in culture: 1. **Films and Television**: Einstein has been portrayed in numerous films and series, often highlighting his scientific achievements and personal life.
Bose-Einstein correlations refer to a statistical phenomenon that arises in quantum mechanics, specifically in the context of indistinguishable particles that follow Bose-Einstein statistics. These particles, known as bosons, include examples like photons (light particles) and helium-4 atoms. The essential aspect of Bose-Einstein statistics is that, unlike fermions (which follow the Pauli exclusion principle and cannot occupy the same quantum state), bosons can occupy the same quantum state.
The phrase "brain of Albert Einstein" generally refers to the physical brain of the renowned physicist Albert Einstein, which became a subject of fascination and study after his death in 1955. Upon his passing, Einstein's brain was removed for examination by Dr. Thomas Stoltz Harvey, the pathologist who conducted the autopsy at Princeton Hospital. Harvey which was controversial and raised ethical questions, believed that studying Einstein's brain could provide insights into the neurological basis of his extraordinary intelligence.
The Einstein–Infeld–Hoffmann (EIH) equations are a set of equations derived from the Einstein field equations of general relativity, specifically for the purpose of describing the motion of bodies in a gravitational field produced by other bodies. They are particularly significant in the context of the study of gravitational dynamics and celestial mechanics. The EIH equations were formulated by Albert Einstein, Leopold Infeld, and Hugo Hoffmann in the 1930s.
The Einstein radius is a concept from gravitational lensing, which is the bending of light caused by the gravitational field of massive objects, such as galaxies or galaxy clusters. When a light source (like a distant star or galaxy) is perfectly aligned with a massive foreground object (the lens), the light from the source can be bent around the lens, creating multiple images or a ring-like structure known as an "Einstein ring.
An Einstein ring is a fascinating astronomical phenomenon that occurs due to gravitational lensing, a prediction of Albert Einstein's General Theory of Relativity. This effect takes place when a massive object, like a galaxy or a cluster of galaxies, lies directly between an observer (such as Earth) and a more distant source of light (like a galaxy or a quasar). When the gravitational field of the foreground object distorts the spacetime around it, it bends the light from the background object.
The Sorites paradox, also known as the "paradox of the heap," is a philosophical problem that arises from vague predicates and concerns concepts that do not have precise boundaries. The term "sorites" comes from the Greek word for "heap.
Einstein synchronization is a procedure used in the context of special relativity to synchronize clocks in different locations. The concept was introduced by Albert Einstein in his 1905 paper on special relativity. The idea involves using light signals to synchronize two clocks. Suppose you have two clocks, one at point A and another at a distant point B. The process works as follows: 1. **Send a Light Signal:** A light signal is emitted from clock A towards clock B at time \( t_A \).
The Einstein–de Sitter universe is a specific cosmological model that describes a particular type of expanding universe within the framework of general relativity.
The General Relativity priority dispute refers to the controversy surrounding the credit for the development of the theory of general relativity, which describes the gravitational force as a curvature of spacetime caused by mass and energy. This dispute primarily involved two key figures: Albert Einstein and the mathematician David Hilbert. ### Background 1. **Einstein's Work**: Einstein began formulating the theory of general relativity around 1907, culminating in a published paper in 1915.
Infinite derivative gravity is a theoretical framework in the field of quantum gravity that attempts to address some of the challenges associated with traditional theories of gravity, especially in the context of unifying gravity with quantum mechanics. The main idea behind infinite derivative gravity is to modify the Einstein-Hilbert action (the action used in General Relativity) by including terms with infinitely many derivatives of the metric field, instead of just the usual second derivatives that appear in General Relativity.
Alchemy in the medieval Islamic world was a philosophical and proto-scientific tradition that emerged from earlier Greco-Roman and Hellenistic influences and significantly evolved in the Islamic Golden Age (approximately the 8th to the 14th centuries). Islamic alchemy encompassed a range of practices, beliefs, and theories about the nature of matter, transformation, and the pursuit of knowledge, blending concepts from science, mysticism, and spiritual philosophy.

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