Equation 8 · Part 2 · An Optical Fabric Turns Off-Package Memory Into an Extension of the Die
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
The amortization term in that denominator matters more than it looks at first pass. A fixed integration cost — the extra laser sources, the photonic-PIC yield loss, the switch die itself — divided across a single module looks catastrophic; divided across sixteen thousand modules in a hyperscale fleet looks close to free. That is precisely why belongs in the model as a scale-dependent term rather than a single constant: the same fabric can fail the copper baseline at pilot volumes and clear it easily at fleet volumes, and a headline efficiency number has every incentive to quote whichever scale flatters it without ever stating which one that was. Neither Celestial AI’s nor…
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 →
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