Quote from: garlonicon on November 30, 2024, 01:10:09 PM

Joined parts should not be used directly as a proof, by checking just your public key. You should instead hash all public keys, and put it into R-value, and then prove it, by revealing a commitment. In other case, you can prove, that anyone was a part of your multisig.

Well, it's not necessarily proof that you signed one of the signatures in the aggregated Schnorr, but just proof that you can sign it.

To deterministically prove that it was indeed you who signed that particular signature, you'd need to use something like BIP 322 and paste some PGP signed message output inside it along with date, block hash etc.

This "nested signature" allows people with your PGP key or any other alternative form of cryptographic identification to know that in fact, you created the associated transaction.

Of course, it can be placed in an aggregated Schnorr signature if the BIP is implemented, and all other parties create their own as well.