Player progress tracking in video games refers to the methods and systems used to monitor and record a player's achievements, milestones, and overall advancement within a game. This can include a range of elements, such as: 1. **Levels and Experience Points (XP)**: Many games feature leveling systems where players accumulate experience points through gameplay, which contribute to advancing to higher levels.
VTime XR is a social virtual reality (VR) platform developed by vTime XR Ltd. It allows users to interact with others in a mixed-reality environment, combining elements of both virtual reality and augmented reality. The platform supports real-time voice and video communication, enabling users to meet in virtual spaces, share experiences, and engage in social interactions.
Tangerine Computer Systems is a company that specializes in providing software solutions and IT services, particularly focused on the education sector. Founded in the 1980s, the company has developed a range of products aimed at helping educational institutions manage various administrative tasks, such as student information systems, enrollment management, and reporting tools. Tangerine's software solutions are designed to streamline operations for schools, colleges, and universities, enhancing the efficiency of educational administration.
Adolf Lindenbaum was a significant figure in the field of mathematics, particularly known for his contributions to mathematical logic and set theory. He is noted for his work in the early to mid-20th century. Lindenbaum's most notable contribution is perhaps the Lindenbaum Extension, a method used in model theory to extend a consistent set of sentences to a complete and consistent set. This concept is an important tool in understanding model completeness and the completeness theorem in logic.
Eino Kaila (1890–1958) was a notable Finnish philosopher and psychologist known for his contributions to the fields of philosophy, psychology, and education. He was particularly influential in the development of scientific psychology in Finland and was one of the leading figures in Finnish philosophical thought during his time. Kaila is recognized for integrating ideas from various philosophical traditions and for his work on the nature of human consciousness and perception. He also addressed issues related to the philosophy of science and education.
Self-control refers to the ability to regulate emotions, thoughts, and behaviors in the face of temptations and impulses. It involves resisting short-term desires in order to achieve long-term goals and may encompass various aspects, such as emotional regulation, impulse control, and the ability to delay gratification.
TTBB is a vocal arrangement designation that stands for "Tenor 1, Tenor 2, Baritone, and Bass." It refers to a four-part men's chorus or vocal ensemble layout, where two parts are sung by tenors, one part by a baritone (which typically sings in a range between tenor and bass), and one part by a bass. This arrangement is commonly used in choral music, allowing for rich harmonies and varied vocal textures.
Smog is a type of air pollution that results from the combination of smoke and fog, typically characterized by a thick, hazy appearance. It often occurs in urban areas where industrial emissions, vehicle exhaust, and other pollutants are prevalent. There are two main types of smog: 1. **Classical Smog**: Often referred to as "London smog," this type is primarily composed of sulfur dioxide and particulate matter.
The term "majority" generally refers to more than half of a total number of votes, members, or elements in a particular context. It can be applied in various fields such as politics, law, and sociology. Here are a few common contexts in which "majority" is used: 1. **Voting**: In an election or a decision-making process, a majority means that a candidate, proposal, or decision receives more than 50% of the votes cast.
Edugraphic is a term that generally refers to a graphic representation or visual illustration related to education. This can encompass a variety of formats, including infographics, charts, diagrams, and other visual tools that convey educational information or data. Edugraphics are often used to present complex concepts, statistics, or learning pathways in a way that is easily understandable and engaging for students, educators, or the general public.
Bertrand's ballot theorem is a result in combinatorics related to voting and elections. It can be stated as follows: Suppose that in an election, candidate A receives \( a \) votes and candidate B receives \( b \) votes, with \( a > b \). If the votes are counted one by one in a random order, the probability that candidate A is always ahead in the vote count throughout the counting process (i.e.
Game theory by Ciro Santilli 40 Updated 2025-07-16
As mentioned at Human Compatible by Stuart J. Russell (2019), game theory can be seen as the part of artificial intelligence that deas with scenarios where multiple intelligent agents are involved.
Lie algebra by Ciro Santilli 40 Updated 2025-07-16
Intuitively, a Lie algebra is a simpler object than a Lie group. Without any extra structure, groups can be very complicated non-linear objects. But a Lie algebra is just an algebra over a field, and one with a restricted bilinear map called the Lie bracket, that has to also be alternating and satisfy the Jacobi identity.
Another important way to think about Lie algebras, is as infinitesimal generators.
Because of the Lie group-Lie algebra correspondence, we know that there is almost a bijection between each Lie group and the corresponding Lie algebra. So it makes sense to try and study the algebra instead of the group itself whenever possible, to try and get insight and proofs in that simpler framework. This is the key reason why people study Lie algebras. One is philosophically reminded of how normal subgroups are a simpler representation of group homomorphisms.
To make things even simpler, because all vector spaces of the same dimension on a given field are isomorphic, the only things we need to specify a Lie group through a Lie algebra are:Note that the Lie bracket can look different under different basis of the Lie algebra however. This is shown for example at Physics from Symmetry by Jakob Schwichtenberg (2015) page 71 for the Lorentz group.
As mentioned at Lie Groups, Physics, and Geometry by Robert Gilmore (2008) Chapter 4 "Lie Algebras", taking the Lie algebra around the identity is mostly a convention, we could treat any other point, and things are more or less equivalent.
Issue voting refers to the practice where voters base their electoral choices primarily on specific issues or policy preferences rather than on party affiliation, candidate personality, or other factors. In issue voting, individuals evaluate candidates or parties based on how closely their positions align with the voter's own views on significant topics, such as the economy, healthcare, education, environment, social justice, and foreign policy.
Quadratic voting (QV) is a voting mechanism designed to aggregate preferences more effectively in situations where individuals have varying levels of interest in an issue. Unlike traditional voting methods, where each voter typically gets one vote per issue, quadratic voting allows individuals to express the intensity of their preferences by allocating votes in a way that reflects how strongly they feel about an issue. In quadratic voting, individuals can buy multiple votes for a particular option, but the cost of the votes increases quadratically.
Equatorial waves are oceanic or atmospheric waves that occur in the equatorial regions of the Earth. These waves are characterized by their unique dynamics and properties influenced by the Earth's rotation, the Coriolis force, and the stratification of the atmosphere or ocean. The most notable types of equatorial waves include: 1. **Equatorial Kelvin Waves**: These are eastward-propagating waves influenced by the Coriolis effect and are characterized by their dispersion relation.

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