Garbled circuits and BitVM3

This new direction is primarily motivated by the substantial increase in efficiency it brings to SNARK verification processes on the Bitcoin network. Specifically, garbled circuits enable more than a thousandfold improvement in the efficiency of BTC bridges, resulting in considerably lower costs associated with these operations.

Exploration into this promising technology is currently being conducted on multiple fronts, with various teams delving into the potential applications and optimizations of garbled circuits. Among the innovative approaches being developed is BitVM3, a system designed to strike an optimal balance among several critical factors: the complexity of implementation, the overhead associated with communication, and the overall cost of proving. The design principles of BitVM3 draw inspiration from Jeremy Rubin's Delbrag scheme, as highlighted in his detailed proposal (Delbrag). A notable advancement introduced with BitVM3 is its ability to verify circuits in plaintext before reblinding them. This feature effectively addresses a major limitation of the Delbrag scheme, which was hindered by the need for either prohibitively expensive circuit correctness proofs or the use of large 200kB disprove scripts. Through these improvements, BitVM3 represents a significant step forward in the development and application of garbled circuits within the Bitcoin ecosystem.