Theory
Physics, mathematics, and algorithms behind Nucleide's core capabilities.
These pages explain the physics, mathematics, and algorithms that Nucleide implements. They are written for analysts and contributors who want to understand why the code behaves the way it does, not just how to call it.
When to read each page
| Page | Read if you are… |
|---|---|
| Depletion | Solving burnup chains and want to understand the Bateman equation, transmutation matrices, and CRAM. |
| Enrichment cascades | Configuring multicomponent enrichment cascades and need the MARC/SWU derivation. |
| Variance reduction | Generating MAGIC weight windows or sampling mesh-based sources. |
| Nuclear data | Looking up nuclide IDs, masses, half-lives, or converting between code-name dialects. |
Relationship to tutorials
The theory pages are companions to the tutorials. A tutorial shows you how to run a calculation; the matching theory page explains the equations and assumptions behind it.
Structure of a theory page
Each page follows the same pattern:
- Overview — what problem the method solves.
- Mathematical details — the governing equations and symbols.
- Algorithm — how Nucleide turns the math into code.
- Worked example — a small hand-verified calculation.
- Assumptions and limitations — explicit list of what is and is not handled.
- Related work beyond Nucleide — adjacent methods in PyNE, OpenMC, and the literature that Nucleide does not (yet) implement.
- References — papers and data sources.