https://www.notebookcheck.net/Scientists-estimate-that-quantum-computers-may-become-powerful-enough-to-crack-the-Bitcoin-encryption-in-a-decade.597437.0.html
Theoretically could happen much faster. I know a few research groups who are specifically researching how to use quantum computing to rapidly break all blockchains. More funding is coming online for this.
I have been saying this for the last 2 years. What are people putting there futures in? Unless there are quantum encrypted crypto currencies everything not is potentially obsolete or can be decrypted by quantum servers.
Sha256 in standard notation has 10^77 possible answers. Current hash power is ~10^18. The distance till we max out sha256 is unfathomable. You could have a millions quantum computers matching the entire current hash rate and we would still be unfathomable distances away. For their to be an attack on the network one would have to control the majority of the hash rate. Unless aliens come down and gift us some computer that is more powerful than all the miners combined I think we're good. The reality is quantum computers will probably just replace ASICs it will take decades from that point to reach capacity. Then we can just fork Bitcoin to sha2048 or something like that. So really just some bad fud or a lack of fundamental math. Or you didn't bother looking up any numbers.
Most probably a troll post. Clear indication is to call SHA256 "encryption".
Actually, quantum blockchain is the next step. What's missing here is just assuming that blockchain itself isn't going to continue to evolve. Many people are already working on this, it isn't something hypothetical.
Forget Bitcoin. It could crack virtually every personal bank account username/password on the planet and drain everything everyone has every made in minutes. Bitcoin is the least of our worries here. It can be hardened all at once. BofA, Barklays, etc, will be fighting this force all on their own.
You don't "encrypt" with SHA-256 or any hashing algorithm. Hashing is a one-way function. Bitcoin uses RSA signatures (public/private asymmetric key pairs) to provide a public ledger of transfers and the hashing algorithm simply provides integrity and verification for the transfers.
Imagine writing an entire article about the sophisticated sha1 "encryption" used by bitcoin. Even defining SHA as "secure HASH algorithm". SHA1 is not encryption! It is a hash!