Denominator: log_2(B_1 / B_0)

The passage around this formula

where $B_0$ is the bandwidth at reference year $t_0$ and $\tau$ is the doubling time implied by the data. Solving for $\tau$ from the two JEDEC anchor points gives $\tau = \frac{t_1 - t_0}{\log_2\!\left(B_1 / B_0\right)} = \frac{2025 - 2022}{\log_2(2.0 / 0.82)} \approx 2.3 \ \text{years}$. Extrapolated naively, ten more years at that doubling time — roughly 4.3 further doublings — would put per-stack bandwidth near 39 terabytes per second by 2035. That number should not be believed as stated, and the reason it should not be believed is itself the analytically interesting point. A two-point fit is not a trend; it is a line drawn through the only two data JEDEC has actually ratified. And it runs well ahead of the general DRAM-and-interconnect bandwidth scaling documented across two decades of hardware by…

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