Sinusoidal by Ciro Santilli 37 Updated 2025-07-16
A function that is either a sine or cosine, i.e. we don't know or care where the origin is exactly.
This is particularly relevant in electronics, where the oscilloscope's time origin is set to match the wave.
Stable Nucleic Acid Lipid Particles (SNALPs) are a type of nanocarrier designed for the delivery of nucleic acids, such as mRNA or siRNA (small interfering RNA), into cells. They represent an advanced formulation of lipid nanoparticles (LNPs) that enhances the stability and efficacy of nucleic acid therapies.
Jim Propp is a mathematician known for his contributions to the field of combinatorics, particularly in areas such as probability theory, random walks, and the mathematics of tiling. He is also recognized for his work in mathematical problem-solving and has been involved in mathematics education and outreach. He has contributed to various publications and has a significant online presence where he shares insights on mathematics.
John Kingman could refer to a few different notable individuals, but the most prominent one is likely the British mathematician John F. C. Kingman. He is known for his work in probabilistic methods and stochastic processes, particularly in areas such as queueing theory and mathematical genetics.

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