For signatures, hash based signatures are quantum computer resistant and are also more secure than any other signature scheme. No reliance on a math problem if you don't count the cryptographic permutation to be one, but then everything relies on it regardless of what scheme is used.
The McEliece cryptosystem[1] is one of finalists in the PQC competition and it's also quite old - developed in 1978. It didn't face as much scrutiny as RSA or ECC due to its large key sizes which resulted in nonexistent adoption.
My understanding is that all the other PQC candidates including Kyber are much newer and far less studied.
The McEliece cryptosystem[1] is one of finalists in the PQC competition and it's also quite old - developed in 1978. It didn't face as much scrutiny as RSA or ECC due to its large key sizes which resulted in nonexistent adoption.
My understanding is that all the other PQC candidates including Kyber are much newer and far less studied.
[1] https://en.wikipedia.org/wiki/McEliece_cryptosystem