Links for 2010-08-05

  • “It’s hard to read Judge Walker’s opinion without sensing that what really won out today was science, methodology, and hard work. Had the proponents of Prop 8 made even a minimal effort to put on a case, to track down real experts, to do more than try to assert their way to legal victory, this would have been a closer case. But faced with one team that mounted a serious effort and another team that did little more than fire up their big, gay boogeyman screensaver for two straight weeks, it wasn’t much of a fight. Judge Walker scolds them at the outset for promising in their trial brief to prove that same-sex marriage would “effect some twenty-three harmful consequences” and then putting on almost no case.”
  • “We present a toy theory that is based on a simple principle: the number of questions about the physical state of a system that are answered must always be equal to the number that are unanswered in a state of maximal knowledge. A wide variety of quantum phenomena are found to have analogues within this toy theory. Such phenomena include: the noncommutativity of measurements, interference, the multiplicity of convex decompositions of a mixed state, the impossibility of discriminating nonorthogonal states, the impossibility of a universal state inverter, the distinction between bi-partite and tri-partite entanglement, the monogamy of pure entanglement, no cloning, no broadcasting, remote steering, teleportation, dense coding, mutually unbiased bases, and many others. The diversity and quality of these analogies is taken as evidence for the view that quantum states are states of incomplete knowledge rather than states of reality.”
  • “The flaw with any play no matter its source material is that drama is about people, not ideas. You can have a play without ideas as long as you have people (not that I’d always go see a play without ideas), but you can’t have it the other way around. We’re watching people experience, take risks, make choices, try, fail, combat, converge, and collide. Ideas may fuel the people, but people and their crises fuel the drama.

    When science plays do fail to be good plays it’s usually because the scientific ideas subsume the desires, conflicts, and fierce wants of the people. The play gets too explanatory, obscure, pedantic, confusing, or just plain boring. But science is not built for boredom. It’s built for amazement, commitment, and at the right moment, paradigm-rattling change. When crafted right, these elements should ignite a stage.”

  • “Given what we now know, from radiotherapy to the legacy of the attacks on Hiroshima and Nagasaki, it is clear that radiation safety limits are far too conservative. Evidently, our bodies have learned through evolution to repair or eliminate damaged cells, with a low failure rate. I suggest the upper limit might be reset at a lifetime total of 5 sieverts, at no more than 0.1 sievert per month. That would be a fraction of a radiotherapy dose, spread over a lifetime.”
  • “[O]ne good thing about working in a building full of physicists is that you always have materials on hand for experiments, yes even bountiful strong magnets and sharks.”
  • “The announcement was made Wednesday by The Giving Pledge, an effort officially launched by Gates and Buffett earlier this year to persuade the richest people in America to commit to giving the majority of their wealth to the philanthropic causes and charitable organizations of their choice, either during their lifetime or after their death.

    In addition to Buffett and Gates — America’s two wealthiest individuals, with a combined net worth of $90 billion, according to Forbes — 38 other billionaires are taking the give-it-away pledge. They include New York Mayor Michael Bloomberg, entertainment executive Barry Diller, Oracle co-founder Larry Ellison, energy tycoon T. Boone Pickens, media mogul Ted Turner, David Rockefeller, film director George Lucas and investor Ronald Perelman.”

  • “If I were a rich man, I’d buy B&N, get rid of all the mass market shelf space, replace it with an Espresso Book Machine, start strong-arming publishers to print and bind really, really nice hardcovers at lower print runs and stock the hell out of those, and open up the B&N in-store ebook store to all devices and platforms (fuck it; even license mobi from Amazon if I can).

    What to do with all that extra big box retail space once I’ve coldly slit the throat of the mass market and trade paperback retail supply chain and replaced it with a POD machine? “

  • “What picture should we draw of the quest for new phenomena after the presentation of a wealth of new results at the international conference on high-energy physics in Paris held last week ? I am speaking in particular of results coming from the experiments at the Tevatron and LHC, which are all studying hadron collisions in search for still unseen effects to both confirm (with the discovery of the Higgs boson) or break down (with the observation of Supersymmetry, new particles, extra dimensions, or still other effects) the present theoretical understanding of fundamental physics which the standard model provides us with.

    In short my question today is, on which signal or phenomenon should we place our chips if we were to bet that the standard model is finally going to break down ?”

  • “In the day job, I’ve been accused repeatedly — to my face and in public — of harboring secret agendas to “do in” this program or that one, of thinking of faculty as piece workers, and of being — in the words of one particularly charming public interlocutor — “just idiotic.” All of those have been in response to budget-driven decisions. None of them suggested realistic alternatives to my ideas; when pressed, none of them even involved a recognition that budgetary decisions need to get made at all. I’ve had to learn not to take the bait, and to recognize the lashing out as a function of propinquity more than anything else. If I’m goring somebody’s ox, it must be because I’m an asshole; surely there’s no such thing as a real resource constraint. When other administrators do the exact same thing — since we’re all working against the same state cuts — well, we’re all just assholes. “

5 comments

  1. Has quant-ph/0401052 changed your opinion on the plausibility of the many-worlds interpretation (or indeed any other interpretation that employs ontic wavefunctions)?

    BTW, Chris Granade coined the term “psi-ontologist” to describe someone who believes in an ontological wavefunction. It might seem a bit harsh, but it is all in good pun.

  2. Honestly, I haven’t had time to read it in detail. I put it in the Links Dump so I could close the browser tab and install software updates.

  3. Stupid question: if one takes an “epistemic” view of wavefunctions, does this necessarily entail believing that there’s some other physical quantity which is “ontic”? And if so, what would this other physical quantity be?

    (I could imagine taking an “epistemic” view as a useful mental tool for thinking about what wavefunctions are without making any “ontic” judgments whatsoever — are “epistemic” and “ontic” actually in opposition?)

  4. Not a stupid question at all!

    I don’t think that the epistemic view of wavefunctions entails anything about whether or not there is a deeper ontic reality on its own, but it does if you combine it with other philosophical convictions. Basically, if you are a realist about scientific theories then there must be some sort of ontic reality, but it you are an anti-realist then this is not necessarily the case.

    Spekkens and co. are basically straightforward realists and have been looking for “epistemic hidden variable models”, i.e. hidden variable models where the wavefunction is not part of the ontology. One can construct such models, but they are rather contrived and it is an open question whether there is any elegant or compelling model of this type. You will sometimes also hear Spekkens muttering about ontologies that are radically different from standard hidden variable ontologies, e.g. relational ontologies, but I am not exactly sure what this would mean in the context of the epistemic program.

    On the other hand, if you are an anti-realist you could follow a line more similar to the Copenhagen interpretation and deny any independent reality for quantum systems. This has its problems, but it is not obviously wrong — I mean, what you were taught in undergraduate physics as the Copenhagen interpretation is obviously wrong, but subtler variants are still standing. The “QBists”, i.e. Chris Fuchs and company are epistemicists of this stripe. Actually, Chris would take exception at being labelled an “anti-realist”, and I might even agree with some aspects of his complaint, but the exact meaning of the term “realism” is probably a philosophical debate too far for a blog comment.

    Personally, I tend to think that we do need an ontology, but that it should be of a radically different type than usually found in hidden variable theories, otherwise it is liable to be ugly due to nonlocality and contextuality. I sometimes play with the idea of constructing an epistemic retrocausal model (Cramer’s transactional interpretation or Aharonov and co.’s 2-state vector formalisms do not qualify since they are realist about the wavefunction). Huw Price came up with a semi-interesting toy theory along these lines recently, but I’d like to see something more principled along the lines of what Spekkens does in his toy theory paper. I am also not completely against Spekkens preferred concept of a “relational” ontology, but my fear about that is that we’d end up being pushed back to something like the Everett interpretation, which would mean being wavefunction epistemicists in name only. In my view, this is what happens in Rovelli’s “relational” interpretation and Mermin’s Ithica interpretation, since there is not much point in being an epistemicist if all the “relations” or “correlations” that you think are ontological are drawn directly from the wavefunction.

  5. Thanks for the response, which is interesting, although I’ll probably have to read quite a bit more to fully digest it.

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