da-bacon

Google has been experimenting with it in chrome https://security.googleblog.com/2016/07/experimenting-with-p... though it is just an experiment in Canary.

In my experience, this view is very prevalent, especially in physics departments. Once you hit the job market it is one of the questions you'll have to answer during interviews, so be prepared! I do agree that there is steady progress, which definitely has helped the field. Context: worked in quantum computing for 10+ years (and was a prof).

Here is the essay he wrote about his realization that he coined the term: "Could Feynman have said this?" www.gnm.cl/emenendez/uploads/Cursos/callate-y-calcula.pdf

Also highly recommend his Boojums.

Definitely. It's actually one of those stories that I wouldn't be surprised if it inspires some new ideas for those who try to do serious research on time travel (or the polite way to say time travel among physicists: closed timelike curves.)

I wrote the first version of Scirate exactly because the number of papers I had to eyeball each day was so high. Now that I've left academia I find it even more useful (so huge thanks to those who rewrote it from scratch)! If you are in quantum computing it definitely helps your sanity.

Eq. 16.

As a grad student in quantum computing we used to have a game where we would race to see who could be the first one to spot the flaw in a paper that claimed an efficient quantum polynomial time algorithm for NP-complete problems.

My bet after a few minutes looking at the paper is Eq. 16. Eq. 15 is computing the clauses with a traditional clause oracle \sum_x |x>|C(x)> where C(x) is a vector of the clauses evaluated on the input x. Eq. 16 claims that one can ignore the first register and this becomes \sum_x |C(x)>. That's not correct: the system is entangled across those two registers, and the partial portion of one of those systems is a mixed state. In particular there is no coherence between the |C(x)> states. The next step relies crucially on this property.

.co is now supported and the full list of supported TLDs is here https://support.google.com/domains/answer/6010092?hl=en

Cris Moore and coworkers found a bunch of these http://tuvalu.santafe.edu/~moore/gallery.html Including this awesome 28-mass one http://tuvalu.santafe.edu/~moore/cubic28.loop.gif

2d versus 1d Turing machine apparently. Here is the paper claiming universality: http://www.dim.uchile.cl/~anmoreir/oficial/langton_dam.pdf

You've discovered how to tell if you are in a physics department or a computer science department :)

I'm not sure "non-Abelian braiding statistics" is the only known robust architecture for QC. Topological qubits are, after all, just systems whose natural states are quantum error correcting codes. Those who chose to pursue quantum error correction directly likely also deserve the moniker of "robust architecture".

I wrote one of these! It was fun and cathartic, as you can imagine. But, because it's complicated, and because I wanted to play around with d3.js, instead of a long diatribe, I built a model of my brain to explain why I left: http://dabacon.org/pontiff/?p=10176

A response concerning the claim that Borges was not political: http://lareviewofbooks.org/essay/borges-politics-and-the-pos...

Also see the follow up with responses from Judea Pearl: http://www.michaelnielsen.org/ddi/guest-post-judea-pearl-on-...

Typing programs in from the magazine taught me how to debug before I ever learned to program.

For a contrary opinion about the book see http://www.cscs.umich.edu/~crshalizi/reviews/wolfram/

(yes I've read the book and mostly agree with that review)

Popper's great. Your reference to Feynman, however, reminded me of this classic qip: “Philosophy of science is about as useful to scientists as ornithology is to birds.” ― Richard P. Feynman

A nice list. The only area I'd add is statistics. Eventually the theory's got to be tested, and understanding the methods experimentalists use is very useful in navigating that world.

http://arxiv.org/abs/1111.1319 for the pre print version of this pay walled publically funded research.

Other uses:

Quantum simulations. Sampling from solutions to linear equations. Shit we haven't discovered yet (you be shocked at how little research there is in quantum computing looking for new algorithms)

Sorry, but no this is not a quantum computer leap. It's a cute paper but woefully far from a complete solution.

Some problems 1) the procedure appears to require 100 percent detection of photons (there is no analysis of this in the paper). This is not practical and ends up being a source of decoherence (the very thing this paper is supposed to avoid) 2) the scheme depends for its gates and construction of a graph state (a kind of resource quantum state) on precise settings of polarized beam splitters, something which will certainly have errors and hence...decoherence again. 3) the author shows how to create a graph state but makes no mention of why this state will persist. Why won't it deco here while waiting for the necessarily adaptive measurement?

Much more interesting than the existence of this "spy center" are the claims of a major breakthrough in crypto:

"According to another top official also involved with the program, the NSA made an enormous breakthrough several years ago in its ability to cryptanalyze, or break, unfathomably complex encryption systems employed by not only governments around the world but also many average computer users in the US."

The article insinuates that it's AES (or something closely related.) That would be pretty amazing.

Making it work at room temperature is probably a greater long term issue. As the temperature goes up the system has a higher probability of accessing states that will make it not function properly (i.e. your logic gates become probabilistic.)

Interesting to see United Airlines on the largest profits and the largest losses. Is this an artifact of their bankruptcy?

Cool result, major bad title. 1) Moore's law is about transistor size, this is about storing bits. 2) As the article does mention, this doesn't work at room temperature, as the bits are too unreliable. The article says this will work at 150 atoms, which sounds about right, but isn't really substantiated by the actual experiment.

I'd also note that while this is a very cool experiment, the fact that it was performed using a scanning tunneling microscope means it's not exactly a practical device :) But as a proof of principle of storing a bit in a few number of atoms, this is a very neat result.

How important quantum physics is for biological systems is in my a very important question for the coming decades. It could turn out to be not important at all except for isolated cases like this. It could turn out to be important, but easy to simulate on a classical computer, and so amenable to study using today's tools. It could turn out to be very important and ubiquitous, so much so that large scale simulation is intractable. If that turns out to be true, then there is a strong case to be made for building quantum computers to attack this problem. I think most scientists think the first or second option is most likely, but if the last opportunity occurs this will represent a major shift.

I think one has to be careful about the engineering challenge of scaling (which I think D-wave has heroically succeeded at so far) versus the question of whether the adiabatic algorithms in their system (finite temperature, imperfections, etc) will scale. I think they can pull of the first challenge (again, an amazing accomplishment), but the second is a question of whether the physics and computer science of their device will scale. I think the good news is that they will probably be able to answer this question in the next few years (thanks to the purchase of one of their devices my Lockheed Martin), but I do worry the answer they get won't be the one they are hoping for.

It's an interesting question: how those who work on quantum algorithms think about quantum algorithms. As someone who worked on quantum algorithms for many years, the interesting intuition that I developed was not what made quantum algorithms tick, but more along the lines of "when is a method likely to NOT yield a quantum speedup." That is I found I could pretty quickly tell when I was doing something that had a nice classical analogy and was therefore doomed to failure. Classic examples where when your intuition about why you might get a speedup involved exploring an exponentially large solution space without some reason that interference could be used to help dig out the interesting parts of the global superposition you created.

An interesting example of how one discovers a quantum algorithm is the story of the NAND tree algorithm (See http://www.scottaaronson.com/blog/?p=207 for a nice explanation.) Quite literally the quantum algorithm was discovered by thinking about interference of particles hoping around, combined with physicists uncanny ability to calculate scattering cross sections. Crazy stuff!

Though one should be careful as the D-wave qubits aren't of the kind that produce a universal quantum computer AND I don't think anyone knows whether their current machines are scaling better than classical analogues.

Indeed that is why many in quantum computing cringe at some of their PR. A minor nit: D-waves machine is programmable, it's just not (thought to be) universal.