
Ask HN: What will happen with BitCoin eventually - dmitryame
Is it the right assumption that when quantum computing becomes a reality, it will render BitCoin (as well as all other cryptocurrencies) obsolete overnight. Can&#x2F;Should anything be done today to prevent this from happening?
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toexitthedonut
Don't think about what will happen to Bitcoin in that situation, because its
hashing algorithm is nothing particularly unique. Think of what will happen to
SHA-1, -2, etc. The NSA is likely already thinking well ahead about this
possibility.

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solomatov
I think, bitcoin will be banned by most of governments earlier than quantum
computing will become widespread to break bitcoin.

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dmitryame
How can you ban something that can not be banned by design?

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solomatov
Powerful countries can easily perform 50% attack and decide which transactions
get confirmed and which not. Effectively, this makes it possible to completely
stop transactions on the network.

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dmitryame
In theory, such an attack is possible, in practice -- very unlikely at this
point given the number of miners out there. Here is what it was in 2015:
[http://www.zerohedge.com/news/2015-11-19/bitcoins-
computing-...](http://www.zerohedge.com/news/2015-11-19/bitcoins-computing-
network-more-powerful-525-googles-and-more-10000-banks) Today it's even higher
than ever: [https://news.bitcoin.com/why-bitcoin-is-close-to-a-record-
br...](https://news.bitcoin.com/why-bitcoin-is-close-to-a-record-
breaking-3-exahashes-processing-power/)

