Von Neumann–Bernays–Gödel (NBG) set theory is a foundational system for mathematics that extends Zermelo-Fraenkel set theory (ZF) by incorporating classes, which are collections of sets that can be too large to be sets themselves. NBG is often considered a more expressive framework than ZF, while still being able to avoid certain paradoxes that can arise in naive set theories.
Monstrous moonshine is a term used in mathematics, specifically in the field of modular forms and algebraic geometry. It refers to a surprising and deep connection between the monster group, which is the largest of the sporadic finite simple groups, and modular functions. The term was introduced by mathematician Richard Borcherds in the context of his work on the representation theory of the monster group.
John Rawls was a prominent American philosopher best known for his contributions to moral and political philosophy. His most influential work is "A Theory of Justice," published in 1971, where he introduces key concepts such as the "original position," "veil of ignorance," and the "difference principle." **Key Works of John Rawls:** 1.
The "original position" is a theoretical construct used in political philosophy, particularly by the American philosopher John Rawls in his work "A Theory of Justice." It is a thought experiment designed to determine the principles of justice that should govern a just society. In the original position, individuals are imagined to be in a hypothetical situation where they are behind a "veil of ignorance.
The Middle-square method is an early algorithm used for generating pseudorandom numbers. It was introduced by the mathematician John von Neumann in the 1940s. The basic idea of the method is to take the square of a number, and then extract the middle digits of the result to form a new number. This new number can then be squared again, and the process can be repeated to generate a sequence of pseudorandom numbers.
Additive K-theory is a branch of algebraic K-theory that focuses on understanding certain additive invariants associated with rings and categories. It can be thought of as a refinement of classical K-theory, emphasizing the structured behavior of additive operations. In general, K-theory studies vector bundles, projective modules, and their relations to the topology of the underlying spaces or algebraic structures.
The Steinberg group, often denoted as \( S_n(R) \), arises in the context of algebraic K-theory and the study of linear algebraic groups, particularly over a commutative ring \( R \). More specifically, the term is typically associated with the special linear group and its associated K-theory.
Tanaka Hisashige (田中久重), also known as Tanaka Hisashige and sometimes referred to as the "Thomas Edison of Japan," was a prominent Japanese inventor and businessman during the late Edo period and early Meiji period. He was born in 1799 and passed away in 1881. Tanaka was known for his contributions to various fields, particularly in the development of mechanical devices and technology.
DNS-based Authentication of Named Entities (DANE) is a security protocol that allows authentication of digital certificates using the Domain Name System (DNS). DANE combines the use of DNSSEC (Domain Name System Security Extensions) with the certificate management capabilities of Transport Layer Security (TLS) to provide an additional layer of security for services using SSL/TLS.
Rangaunu Harbour is a large, natural harbour located on the northwestern coast of New Zealand's North Island. It is situated in the Northland Region, primarily within the Far North District. The harbour is known for its scenic beauty, diverse ecosystems, and recreational opportunities, including fishing and boating. It is also an important habitat for various bird species and marine life. The area around Rangaunu Harbour is rich in Maori culture and history, and it is often associated with traditional fishing practices.
Ōmāpere is a small locality in New Zealand, located in the Northland region. It is situated near the northern shore of the Hokianga Harbour and is part of the larger Hokianga area, which is known for its natural beauty, rich Māori culture, and historical significance. The area is characterized by stunning landscapes, including sand dunes and forested hills.
The AES (Advanced Encryption Standard) key schedule is the process by which the original encryption key is expanded into a set of round keys, which are used in each round of the AES encryption and decryption processes. AES operates on blocks of data and supports key lengths of 128, 192, or 256 bits, generating a different number of round keys based on the key length. ### Key Schedule Overview 1.
A Certificate Authority (CA) is a trusted entity that issues digital certificates used to verify the legitimacy of organizations and their websites. These digital certificates serve as a form of identification and help secure communications over networks, particularly the internet. Here are some key aspects of a Certificate Authority: 1. **Role in SSL/TLS**: CAs are crucial for enabling secure connections through protocols like SSL (Secure Sockets Layer) and TLS (Transport Layer Security).
A Key Derivation Function (KDF) is a cryptographic algorithm designed to derive one or more secret keys from a keying material, such as a password or a master key. KDFs are important in various applications, particularly in ensuring that keys used for encryption, authentication, and other security purposes are derived securely and efficiently. ### Key Characteristics of KDFs 1.
Key whitening is a cryptographic technique used to enhance the security of block ciphers and other cryptographic algorithms. The main idea behind key whitening is to add additional randomness to the encryption process, thereby making it more resistant to cryptanalysis and attacks. In key whitening, extra bits of key material, called whitening keys, are incorporated into the encryption process. This is typically done by XORing (exclusive OR) these whitening keys with the plaintext before encryption and/or with the ciphertext after encryption.
An Extended Validation Certificate (EV Certificate) is a type of SSL/TLS certificate that provides the highest level of assurance and security for websites. It is meant to give users greater confidence in the identity of the organization behind a website. EV Certificates are issued only after thorough verification of the requesting entity's legal, physical, and operational existence.
OpenIKED is an open-source implementation of the IKEv2 (Internet Key Exchange version 2) protocol, which is used to establish secure communication channels over IP networks, typically in the context of VPNs (Virtual Private Networks). IKEv2 is part of the IPsec suite and is designed to provide mutual authentication and secure key exchange methods, facilitating the creation of secure tunnels. OpenIKED is often appreciated for its simplicity, performance, and security features.
Knowledge ecosystems refer to the interconnected networks of individuals, organizations, technologies, and practices that facilitate the creation, sharing, and utilization of knowledge. Similar to biological ecosystems, these systems thrive on interactions among various elements, each contributing to the overall health and diversity of knowledge within the system. ### Key Components of Knowledge Ecosystems: 1. **Participants**: This includes individuals (e.g., researchers, practitioners, educators) and organizations (e.g.
A Key Encapsulation Mechanism (KEM) is a cryptographic primitive used to securely encapsulate a symmetric key for encryption and decryption purposes. It allows for the secure exchange of symmetric keys between parties in a way that protects them from eavesdroppers. KEMs play a fundamental role in hybrid encryption schemes, where asymmetric cryptography is used to encrypt symmetric keys, which are then used to encrypt the actual message data.
Rotational frequency refers to the number of complete rotations or cycles that an object makes in a given unit of time. It is typically expressed in hertz (Hz), where 1 Hz equals 1 rotation per second. In other words, if an object rotates once every second, its rotational frequency is 1 Hz. Rotational frequency can also be represented in terms of angular velocity, which is often measured in radians per second.

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