Bitcoin Forum

"Quantum computers could crack the code with relative ease, potentially undermining the security of the entire global financial services industry."

http://www.bbc.com/news/business-35886456

Well I'm hiding my Bitcoin under my pillow now, how about you?


More reading on the state of quantum computing:
http://www.pri.org/stories/2016-03-29/scientists-just-created-holy-grail-computing-first-quantum-computer
http://www.theregister.co.uk/2015/12/09/googles_quantum_computer/
http://www.newsweek.com/quantum-computing-breakthrough-paves-way-ultra-powerful-machines-440444
http://www.pcworld.com/article/3044988/this-new-discovery-could-put-quantum-computers-within-closer-reach.html
http://www.ibtimes.com/quantum-computers-move-closer-reality-fredkin-gate-breakthrough-2344047

not shocking me,its normal when people try hard to learn bitcoin encryption and then when they did it,they create quantum computer,this is not only danger for bitcoin,but also every altcoin and online payment. i will hiding my bitcoin on back of my closet.

Quantum entanglent is made up

Quantum entanglement has been long known and provable since the 1940s.

This pops up regularly. If quantumness spurts all over Bitcoin then almost everything else is going to be screwed too. We'll have bigger fish to fry.

Yes, proven by Bell's Theorem.
https://en.wikipedia.org/wiki/Bell's_theorem

Its gettin bigger and bigger :) I really like it  :P

Quantum computers could crack the code with relative ease, does not mean that they will do it all for unlawful purpose.
Things are invented for the betterment and not only for the destruction and hacking purpose.

This has already been discussed for a while and many many times here. I'll sum up why we don't have to worry too much and how quantum computers won't be the end of the world for Bitcoin.

First of all, there are no known quantum computer algorithms which can make hashing sha256 faster or for finding preimages of sha256 hashes or collisions. Even so, Bitcoin is fairly well protected as the difficulty would just adjust and the double sha256 hash puts an extra step in there which would make any attack more difficult.

Secondly, the only way that quantum computers would mess with Bitcoin is by finding the private key to a public key. However, you can protect against this by not reusing addresses. Since the public key is not revealed until a transaction is spent, any attacker would not be able to find the private key to a public key that is not known until it is revealed in a transaction. By that point, the Bitcoin is spent, and although they could attempt to double spend it, I don't think quantum computers bring that speed down to less than ten minutes. The only issue is if people don't include enough fees and the transaction takes a while to become confirmed. Then there could possibly be possibility of the Bitcoin being stolen.

Lastly, I think the developers would be able to come to consensus on a need to hard fork Bitcoin to quantum resistant algorithms should there be need. In fact, they probably will deploy quantum resistant cryptography before quantum computers become advanced and cheap enough to be used by attackers for attacking Bitcoin. Quantum computers will take several years to become commonplace and by that point, I think everyone could come to consensus to upgrade.

first generation of quantum computer as we know them have not the ability to crash sha256 it is already known so bitcoin is safe and especially fiat is safe

because no one will care about cracking bitcoin if you can crack big institutions that are worth much more money

something that in the future might crack sha256 it's not even imaginable in this moment