[remline]

Flying cars not existing has everything to do with the resources they use (public federally controlled airspace which requires every driver to be a pilot.)

Quantum computers have the same barriers as other private space technology. The question to me is how long they will take to go from research toys to hobby toys which has a lot to do with cost and something to do with consumer safety.

[throwaway613834]

Actually I mentioned flying cars due to fuel inefficiency (I automatically assumed it was too low to make them practical) but I neglected to actually check their energy usage, and now that I just did it seems like the maximum efficiency could be on par with a normal car and it would depend on the actual trip, so my mistake on that.

A better example might be artificial intelligence and the AI winters. Like the failure of machine translation despite high hopes in the 1960s. It took us some 50 years to get to where we are now with Google Translate, and it still only works well for some languages. I have no idea how close to human accuracy it will get, so I would neither be surprised if it never does, nor if it does someday.

Anyway, hopefully instead of picking on the particular examples you can see that my point is obviously that people imagined we'd have a lot of things now that we still don't have the technology for today. So the fact that we've done amazing things in certain areas doesn't really say anything regarding this particular issue.

[jamesrcole]

> my point is obviously that people imagined we'd have a lot of things now that we still don't have the technology for today. So the fact that we've done amazing things in certain areas doesn't really say anything regarding this particular issue.

And there's plenty of things that people said were impossible that were achieved.

That doesn't tell us anything regarding quantum computing, either.

Looking at what people said about past things is completely irrelevant to the prospects for some particular potential technology. The only way you can try to judge the prospects for that technology is by actually getting into the details of that technology and how it relates to our current understanding of the world.

[throwaway613834]

> And there's plenty of things that people said were impossible that were achieved. That doesn't tell us anything regarding quantum computing, either.

Exactly. That was never my reasoning either so I'm not sure what you're refuting.

[jamesrcole]

I'm not refuting anything. All your comments have focused on things that people have promised that haven't turned out, which gives one the impression that that somehow applies to quantum computing as well. I'm trying to paint a more balanced picture of the situation.

[remline]

I see your point. I'm just trying to point out that failures of general tech to emerge are quite different than failures of use cases. You need more of a limit preventing the emergence of a Moore's law on entanglements to really make quantum computing go away and not just solve other problems than those originally assumed to be "easy" and months away.