Certificates use a signature to bind an identity to a public key. JWT bearer tokens use a signature to issue an identity, but that don't include the public key

Certificates use a signature to bind an identity to a public key. JWT bearer tokens use a signature to issue an identity, but that don't include the public key of that identity. The issuer has a public key, but the issuee does not. There are plenty of JWTs that are certificates: * proof-of-possession JWTs, * self-issued JWTs, etc...