quantum computing question(s)

[jkthomson <jkthomson@bigfoot.com>]

after browsing http://www.openqubit.org/ I would like to know if any of you
brainy types could speculate on:

how much faster would a quantum computer be with a large number of qbits?
I realize that the technology is only 'technically' feasible now, but what
about in say, 50 years or so?

is there a limit to the exponential growth by adding qbits?  By that, I
mean, even if we used billions of qbits, are there 'hard problems' that are
still unsolvable in an acceptable amount of time?  (I assume there are...)

is there a safe 'keylength' to be using, or is anyone with a non-quantum
processor unable to generate large enough keylengths to avoid being brute
forced?




   

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 james 'keith' thomson <jkthomson@bigfoot.com>  www.bigfoot.com/~ceildh
 jkthomson:C181 991A 405C EAFB 2C46 79B5 B1DC DB78 8196 122D [06.07.98]
 ceildh   :1D79 59AF ED75 5945 6003 8240 DA34 ACCA 9DE4 6BC9 [05.14.98]
 ICQ:354111 <keys> at pgp.mit.edu     ...and former sysop of tnbnog BBS
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