Critical Mass
Critical mass is the minimum amount of fissile material required for a self-sustaining nuclear chain reaction, first calculated for uranium by French physicist Francis Perrin in 1939 and central to both nuclear weapons design and proliferation intelligence.
Critical mass refers to the smallest amount of fissile material needed for a sustained nuclear chain reaction. Francis Perrin, a French scientist, was the first to publish a formula for calculating the critical mass of uranium in 1939.1
Sources
- Hersh, Seymour M. The Samson Option: Israel's Nuclear Arsenal and American Foreign Policy. Random House, 1991. Chapter 2. ↩
Local network
Critical Mass's direct connections. Click any node to navigate, drag to pan, scroll (or pinch) to zoom. + 2‑hop expands the neighborhood one level further.
An interactive diagram of Critical Mass's connections, drawn on a canvas and explored with a pointer. The same connections are listed as links in the Connected and Mentioned-in sections below.
Legend — how to read this graph
- People
- Organizations
- Programs
- Events
- Concepts
- Places
Larger = more mentions across the vault.
Explicit link (wikilink between entries).
Inferred connection (name co-mention) — toggle with “Inferred”.
Gold ring — a bridge entity linking distant clusters.
Accent ring — your current selection.