#### as the good doctor Fedrizzi and his hench-boffins are apparently taking questions...

...could they please answer this? Posted previously at <http://forums.theregister.co.uk/post/626136>, repro'd below.

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I think you're asking a question I've been wondering about ever since this quantum crap started, namely that they were promising too much to be credible. Quantum computation apparently grows (from what I've read) non-linearly as qbits are added [*], yet accuracy is always the problem. I've long wondered if there's a fundamental link between computation and accuracy in that there's an upper limit to one which, if exceeded, starts to eat into the second. But no-one's ever raised this point that I've seen. Anyone here know any better?

[*] for a given unit of computing power, you can expand this by a cube power in 3 dimensions ie. a box 1 foot per side holds 1 unit of computation, double the boxes in each direction & you get a box 2 foot per side & holding 8 units of computation. You can't do better in 3d space, but quantum promises a much higher scaling, so there's a conflict.

"

this has been bugging me for years! I would be genuinely grateful.