Live data from Hacker News

I'm Scott Aaronson, quantum computing/computational complexity researcher. AMA

news.ycombinator.com

371–373 of 373 posts

Re: I'm Scott Aaronson, quantum computing/computational complexity researcher. AMA

#371

Earlier quoted context omitted.

The difference between QC and all those other examples of interference is that, in the case of QC, the interference happens in configuration space rather than ordinary 3-dimensional space. And configuration space is enormous ; it has a dimension that grows exponentially with the number of particles. The number of paths that could interfere with each other to produce a given amplitude is likewise exponential (in that…

Out of all your replies, I THINK that this is the one that helped me grok why QC is different than somehow simulating quantum math in a classical computer. The idea of being able to tap into more than 3 dimensions sounds like something very fundamental, kind of like relativity, and a key aspect of how our universe works that at least I was never aware of (and probably a lot of other people!) Would you consider writin…

Pretty much any intro to QC (and in particular, any of the intros I've written, and linked to elsewhere on this thread) will make the point about Hilbert space (that's what it's called) having a dimension that grows exponentially with the number of particles in your system. This is because every possible classical configuration of the system is its own orthogonal "direction" in Hilbert space, and the full state can be an arbitrary superposition (i.e., complex linear combination) of those directions.

Re: I'm Scott Aaronson, quantum computing/computational complexity researcher. AMA

#372

Earlier quoted context omitted.

My favorite part of my sabbatical in Tel Aviv was having some actual time to do research. My second-favorite part was the hummus. Forrelation is not a “guiding light for quantum deep learning.” I’m not even sure if there’s such a thing as “quantum deep learning” that’s sufficiently well-developed to deserve the name. You can use Forrelation as a separating example for some other quantum learning problems, e.g. k-mean…

Hi Scott, Have you seen https://arxiv.org/abs/1806.09729 ? I would call that quantum deep learning, or more accurately, foundations of quantum deep learning.

No, I hadn't seen that paper; thanks! I don't want to comment on it without having studied it, except to mention that it doesn't make any reference to Forrelation.

Re: I'm Scott Aaronson, quantum computing/computational complexity researcher. AMA

#373

Hey Scott, thanks for doing this. What do you think of the Copenhagen Interpretation especially in light of the delayed choice quantum eraser experiment[0]? I know interpretation of QM is something actual working scientists try to avoid (I know I do such for my little corner of physics) but given how much interpretation informs intuition it's worth considering once in a while. [0] https://en.wikipedia.org/wiki/Delaye…

I confess I get annoyed when people make arguments about the interpretation of quantum mechanics using complicated thought experiments involving lasers and mirrors. Why not just talk about it in the modern way, in terms of qubits and states? :-) For some of my recent thoughts about interpretation of QM, see this blog post, and especially the discussion in the comments section: https://www.scottaaronson.com/blog/?p=36…

I'm a laser physicist, so I think exclusively in terms of lasers and mirrors, but I get your point.
Post reply on HN