A black brane is a theoretical object in the context of string theory and higher-dimensional gravity, particularly in the study of black holes and their generalizations. The term "brane" refers to higher-dimensional objects (short for "membranes") that can exist in various dimensions in string theory, while "black" indicates that the object has the properties of a black hole, such as having an event horizon and being related to the gravitational collapse of matter.
Neil Gehrels was an American astrophysicist and a prominent figure in the field of gamma-ray astronomy. He is best known for his work with the Swift Gamma-Ray Burst Mission, which was launched in 2004 to study gamma-ray bursts (GRBs) and other high-energy cosmic events. Gehrels made significant contributions to the understanding of these mysterious and powerful explosions, which are among the brightest events in the universe.
KOI-8 (short for "Kod Obmena Informatsiey 8-bit") is a character encoding system used for representing the Cyrillic alphabet, primarily for the Russian language. It is an 8-bit encoding that includes 128 characters from the ASCII set along with additional characters needed to represent various letters and symbols used in Cyrillic scripts. The KOI-8 encoding was developed in the 1980s and was widely adopted in Russia and other countries using the Cyrillic alphabet.
KOI8-B (Koi8-r) is an 8-bit character encoding designed for representing Cyrillic characters used in the Russian language. It is part of the KOI8 family of encodings, which were developed to accommodate the needs of Russian and other Slavic languages on early computer systems. KOI8-B includes the standard ASCII characters along with additional characters needed for Cyrillic scripts, mapping the letters of the Cyrillic alphabet to specific byte values.
The Wilkie investment model, also known as the Wilkie Framework, is a financial model used primarily in the context of investment for life insurance companies and pension funds. Developed by actuary David Wilkie in the 1980s, this model provides a stochastic approach to forecasting asset returns and liabilities, allowing for a more nuanced evaluation of investment risks and returns over time.
The Soviet Union developed a number of microprocessors during the Cold War era, primarily for military and civilian applications. Below is a list of some notable Soviet microprocessors: 1. **K580** - A family of microprocessors based on the Intel 8080 and Zilog Z80 architecture. They were used in various computing systems.
Surface gravity refers to the gravitational acceleration experienced at the surface of a celestial body, such as a planet, moon, or star. It is a measure of how strongly the body attracts objects toward its center due to gravity. Surface gravity can be calculated using the formula: \[ g = \frac{G \cdot M}{r^2} \] Where: - \( g \) is the surface gravity, - \( G \) is the gravitational constant (\(6.
"DONE" can refer to various concepts depending on the context. Here are a few interpretations: 1. **General Term**: In everyday language, "done" means something has been completed or finished. For example, "I am done with my homework" indicates that the homework task is complete. 2. **Project Management**: In project management, "done" often relates to completed tasks or milestones. It's essential for tracking progress and ensuring that all criteria for completion have been met.
Deep tech by Ciro Santilli 40 Updated 2025-07-16
Ciro Santilli is a fan of this late 2010's buzzword.
It basically came about because of the endless stream of useless software startups made since the 2000's by one or two people with no investments with the continued increase in computers and Internet speeds until the great wall was reached.
Deep tech means not one of those. More specifically, it means technologies that require significant investment in expensive materials and laboratory equipment to progress, such as molecular biology technologies and quantum computing.
And it basically comes down to technologies that wrestle with the fundamental laws of physics rather than software data wrangling.
Computers are of course limited by the laws of physics, but those are much hidden by several layers of indirection.
Full visibility, and full control, make computer tasks be tasks that eventually always work out more or less as expected.
The same does not hold true when real Physics is involved.
Physics is brutal.
To start with, you can't even see your system very clearly, and often doing so requires altering its behaviour.
For example, in molecular biology, most great discoveries are made after some new technique is made to be able to observe smaller things.
But you often have to kill your cells to make those observations, which makes it very hard to understand how they work dynamically.
What we would really want would be to track every single protein as it goes about inside the cell. But that is likely an impossible dream.
The same for the brain. If we had observations of every neuron, how long would it take to understand it? Not long, people are really good at reverse engineering things when there is enough information available to do so, see also science is the reverse engineering of nature.
Then, even when you start to see the system, you might have a very hard time controlling it, because it is so fragile. This is basically the case of quantum computing in 2020.
It is for those reasons that deep tech is so exciting.
The next big things will come from deep tech. Failure is always a possibility, and you can't know before you try.
But that's also why its so fun to dare.
Stuff that Ciro Santilli considers "deep tech" as of 2020:
The Paczyński–Wiita potential is a mathematical formulation used in the study of general relativity, particularly in the context of modeling the gravitational field around a Schwarzschild black hole. It provides a way to simplify the analysis of particle motion in strong gravitational fields by introducing an effective potential.
Anaxarchus was a Greek philosopher from the ancient school of materialism, often associated with the Cynic and Epicurean movements. He lived during the 4th century BCE and is known for being a disciple of Democritus, a pre-Socratic philosopher who contributed to atomic theory. Anaxarchus is notable for his teachings on ethics and his defense of pleasure as the highest good, a key aspect of Epicurean philosophy.
The Scientific Research Institute of System Development (NII System Development) is an organization based in Russia that focuses on research and development in various areas of technology and systems engineering. It typically engages in projects related to computer science, systems analysis, software engineering, and related fields. Such institutes often collaborate with other academic, governmental, and private sector entities to advance scientific knowledge and develop innovative solutions.
Felisa Núñez Cubero is a prominent figure in the field of social work and social intervention in Spain. She is known for her contributions to social work education, research, and practice. Her work often focuses on social welfare policies, community development, and the improvement of social services.
The term "FAC System" could refer to various contexts, depending on the industry or field. Without more specific context, it's challenging to provide a precise definition. However, here are a few possibilities: 1. **Facility Access Control (FAC)**: In security and management, a FAC system is used to control access to buildings or sensitive areas. It typically involves the use of electronic systems like keycards, biometric scanners, or RFID technology to regulate who can enter specific areas.
Nandini Trivedi could refer to a person, a project, a brand, or something else, but without additional context, it is difficult to provide specific information.
Magic state distillation is a technique used in quantum computing to produce "magic states," which are specific quantum states that enable universal quantum computation. These states are crucial for implementing certain quantum algorithms and error-correcting codes, as they allow for the realization of non-Clifford gates—gates that cannot be efficiently simulated by classical algorithms.
A Planck star is a theoretical concept in the realm of quantum gravity, particularly in the context of certain models that attempt to unify quantum mechanics and general relativity. The idea was proposed by physicist Carlo Rovelli and others as part of an effort to understand the behaviors of black holes and the nature of singularities. In simple terms, a Planck star is thought to be a hypothetical state of matter that represents the quantum gravitational state of a black hole.
The Reissner–Nordström metric is a solution to the equations of general relativity that describes the spacetime geometry outside of a charged, non-rotating, spherically symmetric mass. It generalizes the Schwarzschild solution, which describes the gravitational field of a non-charged mass, by including the effects of electric charge.
Conditional probability distribution refers to the probability distribution of a subset of random variables given the values of other random variables. It allows us to understand how the probability of certain outcomes changes when we have additional information about other related variables. In mathematical terms, given two random variables \(X\) and \(Y\), the conditional probability distribution of \(Y\) given \(X\) is denoted as \(P(Y | X)\).
Nintendo Labo is an innovative line of do-it-yourself (DIY) construction kits created by Nintendo, designed to be used with the Nintendo Switch console. Launched in April 2018, Labo combines physical crafting with digital gaming, allowing players to build various cardboard creations—known as "Toy-Con"—that can interact with the Switch.

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