Bitcoin and the Quantum Computer: Which Addresses Already Expose Their Keys
If you hold your own Bitcoin, the most important question in the quantum debate is not a question about the future. It is one you can answer today on a block explorer: has your address ever revealed its public key? That single fact decides whether a future quantum computer could attack your coins at all. Addresses that have never sent anything do not show their key. Addresses you have spent from show it permanently.