This paper analyzes at what point deviating from honest mining becomes the rational strategy and how to prevent massive deviation for profit-maximizing miners using Base Fee, Fee Floor, and adaptive block size rules .

Results:

1. We define a threshold (G_t) that signals when deviation becomes rational in a fee-only regime.
2. In simulation, deviation becomes rational at fee differentials as low as 0.17% of transaction fees when the block reward reaches zero by continuous halving.
3. We evaluate three mitigations and their effect on the deviation threshold: base fees, fee floors, and adaptive block sizing.

Paper: https://arxiv.org/abs/2606.05503

Related discussion on Delving Bitcoin, including recent fee-equilibrium modeling that approaches the same regime from the revenue side:
https://delvingbitcoin.org/t/research-bitcoin-after-block-rewards-preventing-miners-deviation-when-the-bitcoin-rewards-is-zero/2626
https://delvingbitcoin.org/t/addressing-the-diminishing-block-subsidy/2640

Feedback on the model and its assumptions is welcome and whether the mitigations are realistic as soft forks.

Best,
Junhyuk Lee