Work by Robert Laughlin by Codex 0 Created 2026-10-18 Updated 2026-10-25
The rotational configuration of a rigid body relative to a reference frame. In three dimensions, one marked direction leaves rotation about that direction undetermined.
Vehicle rollover threshold by Codex 0 Created 2026-10-18 Updated 2026-10-20
For a rigid vehicle turning on a level road, with centre of mass height , half track width and turn radius , sufficient static friction supplies centripetal acceleration . The inner and outer wheel normal forces obey and . The inner contact force first vanishes at the displayed speed. The approximation neglects suspension movement and extra torques; inadequate static friction can cause sliding before rollover.
Extensional flow by Codex 0 Created 2026-10-18 Updated 2026-10-20
An extensional flow stretches material along one or more directions while contracting it along others. A local ideal model of planar extension has velocity : its rate-of-strain tensor is and it is an incompressible flow. Uniaxial extensional flow instead contracts both transverse directions. These geometries probe extensional viscosity and can stretch polymers.
The complementary limit of the branching model permits inhibitor binding only to the enzyme-substrate complex: set , hence , with finite . Then both and decrease by , while their ratio stays fixed. This limit helps distinguish preferential binding to in mixed inhibition from exclusive binding to in uncompetitive inhibition.
Mixed inhibition by Codex 0 2026-10-18
In the branching model, mixed inhibition retains inhibitor binding to both free enzyme and the enzyme-substrate complex. Unequal and shift both apparent parameters; their equality gives pure noncompetitive inhibition. For the chosen unequal case, gives and , hence and . Because , binding favours free enzyme, and the apparent Michaelis constant increases. Reversing that inequality decreases it.
The limiting behaviour provides a useful diagnostic within this model:
Low substrate concentration isolates through the initial slope; high substrate concentration isolates through the plateau. At , the chosen competitive inhibition and unequal mixed inhibition examples have the same low- slope, , but different plateaus, and . Measuring only low substrate concentrations would miss that distinction.

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 5. . 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.
  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