I am new to the forum, and was curious about future ideas related to Post Quantum Cryptography and security protocols.
What will an evolved blockchain look like should the threat of practical Quantum computing become real?
Although Quantum Supremacy appears technologically implausible, at least in the foreseeable future – It will have the potential to disrupt the integral cryptographic protocols we rely upon today, Asymmetric, Symmetric, and collectively , HTTPS.
In order for existing Symmetric systems to function with integrity (including both blockchain and HTTPS as a whole) the exchange of the Private Key must remain private.
Besides the arguably rudimentary solution, of longer keys/passwords to combat Classical<Quantum inferiority with respect to cryptography, what could the mathematical building blocks of the digital future be like? And subsequently, will these new, theoretical building blocks also require the ability to protect us from retrospective decryption?