Equation 9 · 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 copper side of the ratio fares only slightly better, and for an instructive reason: the closest available real-world figure is not a clean memory-subsystem number either. NVIDIA’s H200 accelerator ships 141 gigabytes of HBM3e and delivers 4.8 terabytes per second of memory bandwidth at a rated thermal design power of up to 700 watts in its SXM configuration [ 5 ] . Dividing one by the other gives a bandwidth-per-watt figure for the whole package — but the whole package’s power budget includes its compute cores, not only its memory interface, and there is no public disclosure that isolates how many of those 700 watts the HBM3e subsystem itself actually draws. Using the whole-package…
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.