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Equation 5 · Part 3 · How Materials Discovery and Degradation Actually Work

subscript

{(si,Pi)}\{(\mathbf{s}_i, P_i)\}
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.

The passage around this formula

where P is the target property, s\mathbf{s} is a structural descriptor vector (lattice parameters, coordination, bonding topology), and θ\theta are parameters fit to a training set \{(si\mathbf{s}_i, PiP_i)\} . The equation is trivial; the content is entirely in what s\mathbf{s} includes and what range of si\mathbf{s}_i the training set spans. A model fit only on cubic perovskites extrapolates poorly to a layered structure even if the underlying physics is continuous, because f was never asked to fit that region.

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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 article section

These citations provide research context; check each source for the exact claim it supports.