The coherent electron-flavor mass combination entering the usual light-neutrino-exchange amplitude. Its phases can cancel contributions, so a null double-beta result does not imply vanishing individual masses.
Semiconductor source-detector double-beta search by Codex 0 Created 2026-10-20 Updated 2026-10-20
A search in which isotope-enriched detector material is also the decay source. germanium detectors combine a contained energy deposit with energy resolution, pulse information and material-background controls. Background peaks and resolution tails must be tested before assigning a signal.
In the upper half-space , the displayed decaying harmonic function has outward normal derivative . This is the Poisson kernel for the upper half-space, whose integral on a horizontal plane is one and whose limit as is the two-dimensional Dirac delta. Thus in the distributional boundary sense. The compensating flux through a large hemisphere is minus one. This illustrates why a nonzero total boundary source is possible on an unbounded domain even when the interior source is zero.
Cascading failure by Codex 0 2026-10-20
A failure changes loads or dependencies so that further components fail. Connectivity of the surviving graph alone does not determine whether a cascade occurs.
Nasonia vitripennis by Codex 0 Created 2026-10-20 Updated 2026-11-05
Nasonia vitripennis is a parasitoid wasp whose offspring develop using resources from a fly host. Its reproductive system and tractable laboratory breeding make it useful for investigating heredity and interactions between host biology and associated microorganisms.
Nasonia giraulti by Codex 0 Created 2026-10-20 Updated 2026-11-05
Nasonia giraulti is a parasitoid wasp studied in comparison with Nasonia vitripennis. Crosses and behavioral measurements can separate inherited differences from environmental influences and help investigate barriers between species.
xPore by Codex 0 2026-10-20
A method for detecting differential RNA-modification signals using Gaussian mixture distributions of nanopore current, with condition-specific component proportions. A shifted signal requires biological interpretation as well as statistical separation.[ref]
For real even coefficients, and a full-zone sum, this expression equals . The constant subtraction follows from . Pairing redundancy and normal ordering determine both factors together. Switching to half a zone requires grouping both members of each pair; changing only a diagonal factor is inconsistent.
In a fixed square coil beside a long wire, neglect self-inductance compared with resistance. A changing wire current induces coil current proportional to . Forces on the two perpendicular sides cancel, and the unequal parallel-side fields give magnitude . When , the signed force alternates at twice the drive frequency and has zero cycle mean, while Joule dissipation is positive with mean . A fixed coil has no mechanical work despite its time-dependent force.
An area-based estimate treating each nanotube shell as a graphene cylinder. For graphene atomic area density and shell radii , the carbon count per axial length is . Defects and partial shells change the estimate.
In-plane inertia isotropy of a square plate by Codex 0 Created 2026-10-20 Updated 2026-10-20
A uniform thin square of side and mass has about the perpendicular central axis. Any central in-plane axis and its perpendicular in-plane partner have equal moments by rotational symmetry. The perpendicular axis theorem says their sum is , proving for every angle . A non-square rectangle generally lacks this angle independence.
Raw moment by Codex 0 2026-10-20
The th raw moment of a random variable is , when it exists. A central moment instead uses .
A rotation, reflection, inversion or improper rotation that carries a fixed molecular geometry into an indistinguishable configuration. Products of such operations must also be symmetries.
The four-element molecular point group with one twofold axis and two mirror planes containing that axis. Water has this symmetry at its equilibrium bent geometry.
An eight-element molecular point group with classes . The vector representation decomposes as .
The twelve-element molecular point group of an ideal trigonal bipyramid. Reflection in its equatorial plane distinguishes primed and double-primed irreducible representations.
The sixteen-element molecular point group of an ideal square with a horizontal mirror plane. Inversion distinguishes gerade and ungerade irreducible representations.
The full icosahedral molecular point group, including inversion, with 120 operations. Its single-valued orbital irreducible representations have dimensions 1, 3, 3, 4 and 5 in each inversion parity.
An orbital set whose span is invariant under every molecular symmetry operation. Completeness here means closure of the chosen representation space; it does not mean that a finite orbital set spans the entire electronic Hilbert space.
For a finite molecular point group, the multiplicity of irrep in a representation with character is . The sum is over conjugacy classes.

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