subtraction

The passage around this formula

Analysis. A naive extrapolation makes the compressing cadence explicit rather than hiding it. Writing per-lane rate as a function of time, with $R_0$ the most recent standardised rate at time $t_0$ and T the assumed doubling period: $R(t) = R_0 \cdot 2^{(t - t_0)/T}$. Anchoring at $R_0$ = 200 Gb/s per lane, $t_0$ = 2026 , and holding the most recently observed four-year doubling period fixed gives R(2035) = 200 $\cdot$ 2^{9/4} $\approx$ 950 Gb/s per lane by 2035 — essentially a 1 Tb/s single electrical lane. That number is offered to be doubted, not believed. The assumption it encodes — that the doubling period keeps compressing on a fixed clock rather than lengthening as channel loss and signal-to-noise margin close…

Read this part in the article →