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Equation 13 · Part 2 · How AI for Science and Medicine Actually Works

subscript

euve_{uv}
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 hv(k)h_v^{(k)} is node v ’s representation after k rounds of message passing, euve_{uv} is the edge connecting it to neighbour u , and ψ\psi and ϕ\phi are learned functions — the same general operation GNoME’s crystal-graph network applies to atoms and bonds, applied here to points on a sphere and the physical processes connecting them. GraphCast predicts five surface variables and six atmospheric variables across thirty-seven pressure levels, ten days ahead, at six-hour steps [ 5 ] .

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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 surrounding passage

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