Habemus Papam(s)!

fumata bianca
The conclave has reached an agreement. The new quantum papal dynasty will be a triumvirate consisting of:

  • Charlie Bennett
  • Aram Harrow
  • Steve Flammia

For those of you concerned about having three pontiffs at the same time, fear not: there is historical precedence. Urbi et Orbi.

The Quantum Interregnum Decoherence Continues

The College of Cardinals has been in conclave for over a month now and leaks to the public indicate that the cardinals are still stalemated.  What does this portend for the world?  The end?  A new beginning?  Only entropy (which others call time) will tell.

Quantum Interregnum!


The Vicar of Randomization hereby informs the readers of this blog that the Quantum Pontiff Dave Bacon XLII has decohered.  He further informs the readers of this blog that the entire Quantum Pontiff blog is in Justitium and hopes that the readers will refrain from acting like Canucks fans after losing the Stanley Cup.
The College of Cardinals will begin conclave in the coming days, please stay tuned to this chimney.

Goodnight CSE

good night room

goodnight nom de plume

goodnight notebooks

goodnight tests

goodnight grants

goodnight Mike and goodnight Ike

goodnight publish

and goodnight perish

goodnight whiteboard

goodnight star, goodnight air
goodnight noises everywhere.

Oh the Places I've Been!

In 1996 I participated in Caltech‘s Summer Undergraduate Research Fellowship program under the direction of two postdocs, Nicolas Cerf and Chris Adami (their big boss now works the halls of D.C.) The research project I worked on was to try to see whether quantum computers could efficiently solve NP-complete problems. Or as I like to say, my SURF was spent bashing my head up against the wall (and getting damn good at tensor products and spotting non-linear transforms, as you can see from my SURF writeup. John Preskill told me after my talk, in the first words he ever uttered in my direction: “that was a hard problem you worked on.”)
My SURF project was not my first introduction to quantum computing, but it was the first time I’d gotten a chance to bash my head up against the field, and something must have stuck. Because when I went to grad school in Berkeley in 1997, after a year of taking astrophysics courses (if the cosmic microwave background was distributed this way or that way on the sky, this or that cosmological model could be ruled out, how cool is that!) I stumbled back into quantum computing through the group of Chemistry Professor K. Birgitta Whaley and her postdoc Daniel Lidar. My first paper in quantum computing was published in 1999, and I’ve been a proud participant in the growing field of quantum information science ever sense.
Now that I’ve decided that it is time for a change and I’m moving out of the ivory tower and into the real world (academics, you see, manufacture their own reality, which is why they call everything outside of academia “the real world”), I thought it would be fun to indulge in a little bit of egotistical self-reflection, cataloging the joys that a decade plus spent in quantum computing has given me.  The joys of all of the papers I’ve written and all of the cool quantum computing stuff I’ve see?  No, that would be too easy.  Instead I thought it would be fund to think about the kind of crazy things that happen to you as life sweeps you along.  Or, as I like to say it, “Oh the places I’ve been!”
[Warning: self-flattering ego-inflating stories ahead!]
Things I’ve gotten to do that were pretty damn awesome:

  • I lectured a rich guy who’d just sold his company for many millions of dollars about quantum computing while standing on the walkway surrounding the 200-inch Hale telescope.  This will definitely be the only time I’ve been driven to give a scientific talk in a limo!
  • Parked my Mazda Miata with QUBITS license plate beside Murray Gell-Mann’s Range Rover sporting the license plate QUARKS while at the Santa Fe Institue.  One day I missed a major missed opportunity because of this.  Ben Schumacher was visiting the Santa Fe Institute… so I had the chance to get a picture of two people who have invented words that start with “Q”, that are in the dictionary, in front of two cars with license plates with those words!  I shall never forgive myself for this missed opportunity.


  • Played Isaac Newton to Scott Aaronson’s Gottfried Leibniz.  Personally I think I got to play the more awesome scientist and damn if that Leibniz didn’t steal calculus from me.

  • Gave a lecture at a summer school in Brisbane, Australia where I discussed a stabilizer code which contained the operators XXXX and ZZZZ. XXXX is the name of a beer in Australia, so I knew this would be awesome for jokes about beer and sleep. Unfortunately I didn’t notice that I had named the stabilizer group that these two operators generated Sex. The subsequent accident jokes had a few people rolling in the aisles.

  • Participated in a joint US/Australia NSF workshop in which I got to see Andrew White grill Australia’s Minister for Industry, Science and Resources(?) about education policy. During that trip I also got my finger stuck in an eye bolt when we were out on a cruise of Sydney Harbor, and had to get unstuck with the help of a stick of butter and an NSF program manager.  Oh, and I also got kicked into a nightclub on that trip.
  • Quantum Beer Night in Berkeley (at the Albatross) became Quantum Margarita Night at Caltech, where it made the list of top geek hangouts in Popular Science!
  • I got to hear Cormac McCarthy tell stories during SFI tea time, and found out that he deeply understands Bell inequalities.  Also at SFI I tied myself up to the corners of the lecture hall during a talk to demonstrate how SU(2) is related to the real world.
  • Got sick of looking at the arXiv every morning and so crowdsourced the daily task of filtering these posts by creating the website scirate.com.  Thank you people for doing so much filtering for me, you really have saved me a lot of time.
  • Gave a talk at Bungie about quantum video games.
  • Gave a talk in which I tried to sound like Martin Luther King Jr (BOMB)
  • Gave a talk that involved the use of subwoofers and speakers (sadly the file for this got corrupted and I no longer have the talk.)
  • Kept students amused during their exams by drawing cartoons:

  • Bought an iPhone and realized that it was a pain to surf for papers on the arXiv, so wrote an iPhone app for browsing the arXiv, arXiview.
  • Got a comment on my blog from a Nobel prize winner in physics.
  • Was once the top hit for the word “pontiff” on google. Take that Beattles!
  • Had a word stolen from me by Stephen Colbert: “Jesi.” Okay, well maybe not, but the ensuing discussion of the proper plural of Jesus is amusing.


Ah the things I’ve got to do.  So far.  Kind of makes me look forward to what kind of craziness is going to happen next 🙂

    QSpeak Announcements for Week Ending 6/3/2011

    • Summer School on “Quantum Information meets Statistical Mechanics”
      ======================================================================= ANNOUNCEMENT Summer School on “Quantum Information meets Statistical Mechanics” —- QI&SM 2011 —- Universidad Complutense de Madrid El Escorial (Madrid), Spain 11 – 15 July 2011 http://www.ucm.es/info/giccucm/Escorial2011 ======================================================================= The Summer School will take place at El Escorial, Spain (http://www.euroforum.es/), … Continue reading
    • QCRYPT Deadline Tomorrow
      Dear Colleague, the submission server for contributed talks will close in a few days: *Deadline for Submission of Abstracts for Contributed Talks: June 1, 2011* QCRYPT will take place on September 12-16, 2011 at ETH Zurich. The conference will feature … Continue reading

    My Favorite D-Wave Future

    As many of you know, D-Wave has a nice paper out about some experiments on one of their eight qubit systems. In addition they have sold one of their systems to the military industrial complex, a.k.a. Lockheed Martin.
    One of the interesting things about the devices they are building is that no one really knows whether it will provide computational speedup over classical computers. In addition to the questions of whether adiabatic quantum algorithms will provide speedups for useful problems, there is also the question of how this speedup will be affected when working at finite temperature. If I were an investor this would worry me, but as a scientist I find the question fascinating and hope they can continue to push their system in interesting directions. Of course if I were an investor I’d probably be some multimillionaire who probably has an odd risk aversion profile 🙂
    A fun question to ponder, at least for me, is what will eventually happen to D-wave, in, say, ten years. Of course there are the most obvious futures. They could run out of funding and close their doors as a device maker and sell their patent porfolio. They could succeed and build machines that do outperform classical computers on relevant hard combinatorial problems. Those two are obvious. BORING.
    But my favorite scenario is as follows. D-wave continues to build larger and larger devices. At the same time they perform even more exhaustive testing of their system. And in the process they discover that there are “noise” sources that they hadn’t really expected. Not noise sources that violate quantum theory or anything, but instead noise sources that end up turning their stoquastic Hamiltonian into a non-stoquastic Hamilotnian. While no one knows how to use the Hamiltonian of D-wave’s machine to build a universal quantum computer, it is entirely possible that such a machine, plus some crazy extra unwanted terms could end up being universal. So while the company is squarely behind the dream of a combinatorial optimizer, it’s not at all impossible that their machine could accidentally be useful for universal adiabatic quantum computation (and of course whether this can be made fault-tolerant is still a major open question, at least for the models with non-degenerate ground states.) Wouldn’t it be hilarious if the noise which most people believe will destroy D-wave’s computational advantage actually turns their machine into a universal quantum computer? Ha!
    So which will it be? And what odds will you give me on each of these possible futures?

    Hoisted From the Comments: Quantum Marriage

    Charlie Bennett comments about an novel use of quantum entanglement:

    Tracy Staedter describes a quantum wedding apparatus built by conceptual artist Jonathon Keats, which briefly entangles two people by illuminating them with entangled photons. Staedter quotes Keats as saying the resulting quantum marriage would literally be broken up by skepticism about it.
    http://news.discovery.com/tech/let-quantum-physics-officiate-your-wedding-110510.html

    Speaking of which, who was it who introduced the idea of monogamy of entanglement?
    (Anyone want to go into business selling a device which shoots entangled photons at you and a nearby person? “The Quantum Entangler” could be used to entangle you with that nearby hottie who you really want to get to know 🙂 )

    dabacon.job = "Software Engineer";

    Some news for the remaining five readers of this blog (hi mom!) After over a decade of time practicing the fine art of quantum computing theorizing, I will be leaving my position in the ivory (okay, you caught me, really it’s brick!) tower of the University of Washington, to take a position as a software engineer at Google starting in the middle of June. That’s right…the Quantum Pontiff has decohered! **groan** Worst quantum to classical joke ever!
    Of course this is a major change, and not one that I have made lightly. There are many things I will miss about quantum computing, and among them are all of the people in the extended quantum computing community who I consider not just colleagues, but also my good friends. I’ve certainly had a blast, and the only things I regret in this first career are things like, oh, not finding an efficient quantum algorithm for graph isomorphism. But hey, who doesn’t wake up every morning regretting not making progress on graph isomorphism? Who!?!? More seriously, for anyone who is considering joining quantum computing, please know that quantum computing is an extremely positive field with funny, amazingly brilliant, and just plain fun people everywhere you look. It is only a matter of time before a large quantum computer is built, and who knows, maybe I’ll see all of you quantum computing people again in a decade when you need to hire a classical to quantum software engineer!
    Of course, I’m also completely and totally stoked for the new opportunity that working at Google will provide (and no, I won’t be doing quantum computing work in my new job.) There will definitely be much learning and hard work ahead for me, but it is exactly those things that I’m looking forward to. Google has had a tremendous impact on the world, and I am very much looking forward to being involved in Google’s great forward march of technology.
    So, onwards and upwards my friends! And thanks for all of the fish!