Smart Contracts, Bitcoin, Bitcoin Sv, Zkp, Zero Knowledge Proofs.
tx.origin or msg.sender. In Bitcoin, we extract QB based on a technique called OP_PUSH_TX. OP_PUSH_TX allows the smart contract (in Tm) to access the spending transaction (Tc), thus enforcing where the bounty goes to the collector’s public key QB, used in ECDH to derive the shared encryption key¹.