Why not, if we create a machine that has capability to calculate processes with a tremendous speed, then why not. Scientists even talk about passing information between  photons on computer chips without them being physically linked. Everything is possible, we just need time. But one thing that I can say for sure is that there will come time when current security will be broken and bitcoin or alternative currencies will have to implement something different.

If someone somehow invents it, over time he may dramatically improve it. For example, first ASIC antminer called S1 had a hashrate of 180 GH/s. Now we have Bitcoin Miner S19 XP Hyd. with a hashrate of 250000 GH/s. Its hashrate is 1388 times higher then the hashrate of S1.

--snip--
[/quote]

It's flawed comparison since S19 XP Hyd. has higher watt usage. Better comparison would be comparing GH/W where S1 has ~0.6 GH/W while S19 XP Hyd. has ~48 GH/W which means 80x energy efficiency.
[/quote]
I didn't keep that in mind because my main priority was comparison of hashrates.