robwoodgate on Nostr: Now Bob can use the magic of ECDH... he takes his private key (p) and the ephemeral ...

Now Bob can use the magic of ECDH... he takes his private key (p) and the ephemeral public key that Alice sent with the ecash (E), and he can calculate the SAME shared secret!

He can now use that shared secret to derive a private key to unlock the ecash.