Equation 1 · Part 7 · Who Builds 2100? The Demographic Engine of Technological Evolution
subscript
subscript
What this part means
The lower label selects a particular version, component, or indexed member of the quantity. For example, x₀ and xₜ can be values at different positions.
Its job in the formula
A subscript distinguishes a version, component, step, or member of a quantity. It does not automatically mean multiplication.
Full expression→subscript→Article meaning
The passage around this formula
Semi-endogenous growth theory, the framework Jones developed and that his 2022 Annual Review of Economics piece surveys, formalizes this into a relationship between population growth and the long-run growth rate of ideas [ 4 ] . Population enters the idea-production function as the stock of people available to search the technological fitness landscape for improvements, and because ideas are non-rival — one firm’s discovery of a better transistor layout does not use up the possibility for another firm to discover a different one — expanding that search population raises the rate of discovery roughly in proportion to its own growth, discounted by how much duplicated effort dilutes the return…
Learn the underlying idea
A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.
Open the illustrated subscripts: which member of a family? guide →
Sources cited in the surrounding passage
These citations provide research context; check each source for the exact claim it supports.