Mapping a Secret Scalar Value between Elliptic Curve Groups [broken]
This document outlines a method to map a secret scalar value
x from one elliptic curve group (secp256k1) to another elliptic curve group (a pairing-friendly curve).
This method leverages a variation of the Schnorr signature scheme to prove that the same secret scalar is used in both groups without revealing the value of
This approach can be useful in applications where compatibility with different cryptographic groups is required. For example, in the context of using the Lightning Network to purchase in a PTLC a key to be used with pairing-based cryptography. In general, it is interesting for Adaptor Signatures, Scriptless Scripts, and Discreet Log Contracts.