[cryptography] How far are we from quantum cryptography?

Ron Garret ron at flownet.com
Mon Jan 26 01:17:10 EST 2015

Perhaps I didn’t state my own skepticism about D-wave in strong-enough terms.  For a 512-bit quantum computer to be useful for cryptography it would have to have 512 mutually entangled qubits and the D-wave machine has at most six.  So they are still a very long way from being useful.  Nonetheless, even six mutually entangled qubits is an impressive engineering achievement (if they in fact achieved it.  It’s not clear that they did.)

Bottom line: you’re almost certainly safe from quantum cryptoanalysis for the next few years.  But for the next few decades the jury is out.

On Jan 25, 2015, at 9:34 PM, Watson Ladd <watsonbladd at gmail.com> wrote:

> On Sun, Jan 25, 2015 at 9:21 PM, Ron Garret <ron at flownet.com> wrote:
>> On Jan 25, 2015, at 9:17 PM, Ryan Carboni <ryacko at gmail.com> wrote:
>>> Actually D-wave supposedly managed 512-Qubits.
>> Yes, but they’re not all mutually entangled.  Each qubit only communicates with six others.  (Even that is pretty impressive though.)
> No, D-wave didn't make a quantum computer capable of running Shor's
> algorithm. It's unclear if D-wave's device even works, and there are
> certain theoretical reasons to suspect it didn't.
> See http://www.scottaaronson.com/blog/?p=1400 for actual people who
> know things saying things.
>> rg
>> _______________________________________________
>> cryptography mailing list
>> cryptography at randombit.net
>> http://lists.randombit.net/mailman/listinfo/cryptography
> -- 
> "Those who would give up Essential Liberty to purchase a little
> Temporary Safety deserve neither  Liberty nor Safety."
> -- Benjamin Franklin

More information about the cryptography mailing list