Given the current hoo-haa going on with respect to the blocksize, I wanted to think about future HARD forks that Bitcoin will almost certainly encounter.
1)
Quantum secure signing algorithm. At some point, I think most would agree , quantum computers will be a reality. We'll have to change bitcoin's signing algos accordingly.
2)
Arbitrary precision maths. When bitcoins are worth 'serious' amounts, 8 decimal places won't be enough.. (.. Happy Days..
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)
.. there are others, but I'm not sure they are essential to bitcoin's survival - anyone think of any
essential ones ?
If doubling the blocksize started a war, which it effectively has, I can't even imagine what trying to implement these features will do.. (Since there are many different ways they could be achieved..)
Will it even be possible to HARD fork so large a change, as instead of 2 camps(Yes and No), there may be 5, 10, or more! and then things will get, very complicated.
The first one would eventually be needed... Or not
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When we have quantum computers, the signing will probably be broken, and Bitcoin as it currently is might not be safe (as in, private keys might be able to be calculated within a lifetime, or maybe in just a few hours. I think that might be possible some day with quantum computing, correct me if I'm wrong
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).
As for the second one... You really trust in Bitcoin's future regarding price
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Well, if the price does reach really high levels that might be needed!
New features won't probably start such a war (at least I certainly hope they won't). Experience will tell everyone that wars aren't good and it will give people the expertise to deal better in hard fork situations due to past experiences.