tag:blogger.com,1999:blog-13869903.post330572116620303185..comments2024-03-29T02:45:10.096-05:00Comments on nanoscale views: Quantum computing - lay of the land, + corporate sponsorshipDouglas Natelsonhttp://www.blogger.com/profile/13340091255404229559noreply@blogger.comBlogger7125tag:blogger.com,1999:blog-13869903.post-56777087736572605272017-01-08T18:59:38.260-06:002017-01-08T18:59:38.260-06:00Anon@4:14, I was streamlining my language, but I w...Anon@4:14, I was streamlining my language, but I would like to read your view on this. Are you taking the view that there really is an evolution of the wave function not described by the Schroedinger equation that takes place during a measurement?Douglas Natelsonhttps://www.blogger.com/profile/13340091255404229559noreply@blogger.comtag:blogger.com,1999:blog-13869903.post-25711491112616587402017-01-04T16:14:26.209-06:002017-01-04T16:14:26.209-06:00Just to point out that, decoherence is not the sam...Just to point out that, decoherence is not the same as collapse of wave function at all!Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-13869903.post-79099202856474163812016-12-07T00:38:27.041-06:002016-12-07T00:38:27.041-06:00The D-wave machine, for all the publicity it gets,...The D-wave machine, for all the publicity it gets, is essentially a glorified spin glass simulator. But you have to give them credit for raising interest in the field, and for spurring tech companies to fund other quantum computing projects.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-13869903.post-20672074079926512912016-12-06T19:45:59.028-06:002016-12-06T19:45:59.028-06:00DanM, they are alive and well, apparently, though ...DanM, they are alive and well, apparently, though their quantum annealer approach doesn't seem to have blown far past classical computers, even for their specialized problems, as had been aggressively forecast. By the way, my post seems to have been prescient, because Science published <a href="http://www.sciencemag.org/news/2016/12/scientists-are-close-building-quantum-computer-can-beat-conventional-one" rel="nofollow">this</a> a few days after I wrote the above. Douglas Natelsonhttps://www.blogger.com/profile/13340091255404229559noreply@blogger.comtag:blogger.com,1999:blog-13869903.post-28379964994492042742016-12-06T14:13:07.686-06:002016-12-06T14:13:07.686-06:00So, following up on your post from almost 10 years...So, following up on your post from almost 10 years (!) ago, what ever became of D wave? I see that they still have not yet initiated the destruction of the universe.DanMnoreply@blogger.comtag:blogger.com,1999:blog-13869903.post-56291325958740692612016-11-27T03:44:21.018-06:002016-11-27T03:44:21.018-06:00Also, the Marcus group experiment shows an interes...Also, the Marcus group experiment shows an interesting electronic signature and length dependence that is consistent with the Majorana modes they were searching for, but, as they point out, the real test will be when they are able to perform <i>time-resolved</i> measurements of the qubit, and demonstrate that it is indeed a very stable phase-coherent memory element.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-13869903.post-9393147525820513602016-11-26T14:37:23.965-06:002016-11-26T14:37:23.965-06:00This is definitely one of the most exciting fields...This is definitely one of the most exciting fields for condensed-matter physicists, because they can now use some fairly deep theoretical concepts and come up with exotic experiments that society at large is finally interested in, and willing to pay for generously. The classic field-effect transistor is nice, but its underlying physics can be explained to high-school students, while concepts such as Majorana zero modes are much more sophisticated, to say the least.<br /><br />It may be worth pointing out that the Delft and Niels Bohr experiments realize (if their conclusions are right) a qubit that is only protected as a <i>memory</i> element, as Kitaev notes in his original paper; some other invention is needed to make the <i>computation</i> robust against decoherence. But I suspect it is only a matter of time before another smart physicist figures out how to build a topological quantum gate, rather than simply a memory element.Anonymousnoreply@blogger.com