Equation 1 · Part 2 · Reactor Phylogenetics: The Family Tree of Fission Power
Symbol A
What this part means
the objectively superior technology, and it can lock in permanently long before the alternative gets a fair trial.
Its job in the formula
A is one of the signed contributions combined to compute the quantity on the left.
Full expression→Symbol A→Article meaning
Where the article explains it
Once pulls ahead by chance or by an unrelated advantage — a submarine program’s development budget, say — the process is self-reinforcing regardless of whether A is the objectively superior technology, and it can lock in permanently long before the alternative gets a fair trial.
The passage around this formula
…by markets, regulators, and accidents is observably real and, in the case of TMI, Chernobyl, and Fukushima, dated and measurable. And the founder-effect and lock-in mechanism Cowan documents is not just analogous to a general economic idea — it is the same model. W. Brian Arthur’s 1989 formalization of competing technologies under increasing returns describes exactly this dynamic as a generalized Pólya urn: two technologies accumulate adopters, and the probability the next adopter chooses technology A over B…
Learn the underlying idea
A variable is a named place for a value. Its letter is a local label: x can mean position in one formula and a data point in another.
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Sources cited in the surrounding passage
- [2] Competing Technologies, Increasing Returns, and Lock-In by Historical Events ↗
- [1] Nuclear Power Reactors: A Study in Technological Lock-in ↗
These citations provide research context; check each source for the exact claim it supports.