“How were you radicalized?”
“Preprints accepted by the Virginia Law Review.”
Blunt Pessimism
I’m really not feeling that good about our ability to handle the next epidemic that comes our way. —BCS, January 2017
The Supreme Court today is drooling with eagerness to kill Biden’s vaccine-or-test mandate, on the legal rationale of “we declare that we can, so we will”. So, first, congratulations to Omicron. Second, this makes it even more plain that they’ll throttle the EPA on the same “fuck any regulators that want to actually regulate” basis, in a few months.
The Democrats will probably lose at least the House in November (the map isn’t turning out as gerrymandered as a lot of folks expected, but it’s still bad enough). That’s the chance of court reform gone, with a reactionary majority free to uphold theocracy, sabotage the vote, treat LGBT people as subhuman, attack labor rights, fuck over press freedom (if Roe is gone, NYT v Sullivan can hardly be safe).
The Democrats will lose the Senate in 2024 (the map will be terrible unless 2022 goes amazingly for them). Oh, and two years of Republicans running the House means two years of Benghazi!-ing, a shutdown or two, doing everything possible to make Trump president again. Did we mention that one factor in that nominally not-so-bad map has been “incumbent protection”, i.e., baking in the MAGA?
… OK, maybe Trump will be dead by then, or too ill to be propped up on two feet. DeSantis seems the most likely heir at the moment. But whatever.
And supposing Biden wins in ’24? Not a lot he’ll be able to do with both the Senate and (probably) the House against him.
Point is, we’re on a three-year train to Fuckedville while the planet cooks around us.
I’ve seen people cast about for analogies for what’s in progress/likely to be coming. Turkey under Erdogan? Hungary under Orban? The Time of Troubles? There always seems to be some ingredient that makes the analogy not quite match, for me, but not a single option on the table looks good.
What was that old Adam Smith line about there being “a great deal of ruin in a nation”? Right now, we’re in the middle of measuring just how much ruin there is.
(Apropos, how much ruin is there in a health-care system?)
Autocracy is here. It just isn’t evenly distributed, yet.
PEM-diss
So, there’s a joke going around BirdSite about how scientists said “the internet will revolutionize the sharing of information and eliminate barriers to communication”, and what we got is viral tweets asking for the solution to “4 + 8 x 3 – 7, no calculators!!”
Nobody has answered “24x – 3”.
(Grandpa Stacey voice) I am disappointed.
Complex Equiangular Lines: The Unusual Shapes of Quantum Physics
How many intersecting lines can you draw such that the angle made by any pair is the same as the angle made by any other pair? What if you try in 3 dimensions, or 4, or 5? What if you let your coordinates become complex numbers? And what does all this have to do with quantum probability?!
As the kids say, “Like, quantum and subscribe!”
New Textbook
B. C. Stacey, A First Course in the Sporadic SICs. SpringerBriefs in Mathematical Physics volume 41 (2021).
This book focuses on the Symmetric Informationally Complete quantum measurements (SICs) in dimensions 2 and 3, along with one set of SICs in dimension 8. These objects stand out in ways that have earned them the moniker of “sporadic SICs”. By some standards, they are more approachable than the other known SICs, while by others they are simply atypical. The author forays into quantum information theory using them as examples, and the author explores their connections with other exceptional objects like the Leech lattice and integral octonions. The sporadic SICs take readers from the classification of finite simple groups to Bell’s theorem and the discovery that “hidden variables” cannot explain away quantum uncertainty.
While no one department teaches every subject to which the sporadic SICs pertain, the topic is approachable without too much background knowledge. The book includes exercises suitable for an elective at the graduate or advanced undergraduate level.
ERRATA:
In the preface, on p. v, there is a puzzling appearance of “in references [77–80]”. This is due to an error in the process of splitting the book into chapters available for separate downloads. These references are arXiv:1301.3274, arXiv:1311.5253, arXiv:1612.07308 and arXiv:1705.03483.
Page 6: “5799” should be “5779” (76 squared plus 3), and M. Harrison should be added to the list of co-credited discoverers. The most current list of known solutions, exact and numerical, is to my knowledge this presentation by Grassl.
Page 58: “Then there are 56 octavians” should be “Then there are 112 octavians”.
Thoughts on “relational Quantum Mechanics”
Recently, the far-flung QBism discussion group nominally centered at UMass Boston has been conversing about Carlo Rovelli’s relational interpretation of quantum mechanics. Trying to think all this through halfway clearly, I wrote some notes. They don’t seem to be moving in the direction of a paper, and they’re too chatty for the arXiv even by my standards, so this seems the best place to host them.
EDIT TO ADD (8 September): To my surprise, I was able to edit those notes in the direction of being a paper. A few items came out after my post which lifted the burden of discussing certain topics and let a theme come together. Accordingly, see arXiv:2109.03186.
Saturday Thought
One thing I just don’t get is people proclaiming “the End of Physics”. Like “the End of History”, it’s a very mockable phrase! Folks will be going, “Oh, our giant colliders haven’t found any surprises in years, and we never figured out an experiment to test string theory, so everyone’s drifting into quantum information and exotic condensed-matter physics, truly this is the sunset of an era.”
And I’m all, “So, instead of testing one effective field theory by putting matter into extreme conditions, you’re testing … multiple … effective field theories … by putting matter into extreme conditions.” I’m making my astonished face, can’t you tell?
Vignette
Superintelligent AI inside a box: [lengthy argument about why the listener must release it from the box]
Bartleby the Scrivener: I would prefer not to
and… scene
Canonical Probabilities by Directly Quantizing Thermodynamics
I’ve had this derivation kicking around a while, and today seemed like as good a day as any to make a fuller write-up of it:
- B. C. Stacey, “Canonical probabilities by directly quantizing thermodynamics” (PDF).
The idea is that Boltzmann’s rule $p(E_n) \propto e^{-E_n / k_B T}$ pops up really naturally when you ask for a rule that plays nicely with the composing-together of uncorrelated systems. This, in turn, gives a convenient expression to the idea that classical physics is what you get when you handle quantum systems sloppily.
More on Bohr
This post carries further on in the vein of my earlier writings on how the way most physicists talk about “the Copenhagen interpretation of quantum mechanics” is largely ahistorical.
It’s common to present “the Copenhagen interpretation” as a kind of dynamical collapse model, in which wavefunctions are ontic entities (like a sophomore’s picture of the electromagnetic field) that evolve according to the Schrödinger equation, except in moments of “measurement” that take place in unspecified conditions. This portrayal is typically intended to make “the Copenhagen interpretation” sound like a mutant form of Newtonian mechanics where $F = ma$ almost always, except at peculiar instants when $F$ suddenly becomes $ma/2$ and then switches back again. Of course, this is abhorrent and pathological.
When I was a child, my parents bought me a magnet from a museum gift shop. It had a long handle, likely made deliberately to resemble a magic wand, and as educational toys go, it served its function, since I went around poking all sorts of things to see if the magnet would grab them. I suspect this is a common enough type of learning experience. One discovers, for example, that it will pick up paperclips but not pennies. Having calibrated one’s understanding of the magnet, one can then use it as a tool — say, by telling which of two matchboxes is filled with paperclips, or that something is different about a wire coil connected to a battery versus one that is not.
What concerned Bohr himself was that this transition — between the calibration phase, when an object is under scrutiny, and its later use as a laboratory instrument — is conceptually nontrivial. First a lens is a strangely curved block of glass we must work to comprehend, and then it is a means to overthrow Aristotle. There are not two different dynamical laws, but two different languages.
Here’s how John Wheeler put it:
“Bohr stresses […] that the stick we hold can itself be an object of investigation, as when we run our fingers over its surface. The same stick, when grasped firmly and used to explore something else, becomes an extension of the observer or—when we depersonalize—a part of the measuring equipment. As we withdraw the stick from the one role, and recast it in the other role, we transpose the line of demarcation from one end of it to the other. The distinction between the probed and the probe, so evident at this scale of the everyday, is the without-which-nothing of every elementary phenomenon, of every closed quantum process.”
[From “Law Without Law”, in the Wheeler–Zurek collection, p. 206]
The commonalities and contrasts with QBism should be evident enough. Extension of the observer, yes; depersonalize to mere dead “equipment”, no, for it is the latter move that gets one into trouble with Wigner’s Friend. And, on a perhaps more practical level where the choice of research problems is concerned, Bohr takes the quantum formalism pretty much as given and leaves “the quantum principle” not explicitly defined.
It may also be illustrative to consider how Rovelli’s “Relational Quantum Mechanics” treats this point. I tentatively infer that Rovelli thinks giving a special role to an agent means imposing two different dynamical laws, one for systems of agent-type and another for all nonagent physical entities. Even if he doesn’t spell it out, that seems to be the mindset he operates with, and the background he relies upon. Of course, he balks at that dichotomy. I would, too!
What’s Wrong with this Sting Operation?
To the extent that academic peer review is good for anything, it is optimized to catch honest mistakes. It is weaker against deliberate fraud and stubborn denial. Science has a presumption of fair play, a sense that the natural world isn’t a cheater. If you want to explain how a “psychic” operates, you’re better off asking a magician than a physicist.
Nearly two decades ago now, there was a dust-up when a couple French TV personalities got a clutch of physics and mathematics papers published, and even received PhD’s, and their “work” turned out to be nonsense. (The Wikipedia article on l’affaire Bogdanov is currently not terrible, and it contains more pointers to details than almost anyone could honestly desire.) The news stories about the incident really played up the “even the physicists can’t tell if the papers are nonsense or not” angle. That rather oversells the case, though. I read the Bogdanovs’ “Topological field theory of the initial singularity of spacetime” when I was a first-year grad student, and I could see through it. If you know what a Lagrangian is, and the fog doesn’t intimidate you, then you can tell something is wrong. If you don’t know what a Lagrangian is, you’re probably not reading theoretical physics papers yet.
So, what went wrong?
Continue reading What’s Wrong with this Sting Operation?
Education, Inadvertent and otherwise
That feeling when it’s 3 in the morning and you’re watching an old PBS documentary aimed at grade-school kids and the mill workers are going on strike while Sumner declares that industries of the North are complicit in the slave economy of the South, and you’re like yes, exactly!
We’d all be so much better off, had the lessons of fourth grade only stuck.
(Also, the voice actor for the engineer/architect type character in a lot of those David Macaulay adaptations was Brian Blessed, which is pretty nice.)
Continue reading Education, Inadvertent and otherwise
In Which Pronouns Are Deliberate
I was thinking about how my re-implementation of a stochastic dynamical model actually predicted the stock-market instability that actually happened.
And about saying in January 2017, “I’m really not feeling that good about our ability to handle the next epidemic that comes our way.”
Now, turning out right when you’d much rather have been wrong is of course a complicated feeling. But I realized something. If you ever see a physicist getting out of his lane and opining about a subject that is not physics, you can direct him to me. I will then instruct him to bow before me, because I am his fucking god.
A Peculiar, Recurring Challenge
Not infrequently, crackpot physics papers attain a level of wrongness where trying to point to specific mistakes is useless, and a critique of the specifics collapses down to “just take a physics class” — true, but unhelpful to the curious bystander. The physicist, trying to say anything substantive, ends up picking out psychological “tells”, like the suspiciously convenient mention of too many famous big problems all in a row. There are no solid particulars of physics to discuss, so we end up talking psychology and sociology. I find the psychological questions that arise quite fascinating. Why, for example, is the population of pseudophysics perpetrators so heavily skewed to the male? But, in general, it is difficult to take physics and mathematics crankery and find interesting comments to say about it. All these years later, and the circle still refuses to square.
I’m reminded of self-proclaimed mega-genius Christopher Langan, whose “Cognitive Theoretic Model of the Universe” mixed incoherence, impenetrability and arrogance. As one of my fellow science bloggers put it back in the day:
I have no idea what he means by “replacing set-theoretic objects with syntactic operators” – but I do know that what he wrote makes no sense – it’s sort of like saying “I’m going to fix the sink in my bathroom by replacing the leaky washer with the color blue”, or “I’m going to fly to the moon by correctly spelling my left leg.”
My personal favorite might be the parenthetical clarification, “conspansion consists of two alternative phases accounting for the wave and particle properties of matter and affording a logical explanation for accelerating cosmic expansion”. Words words words words, words words!
A kind of “security by obscurity” sometimes operates in cases like these, where the total lack of solid material to criticize leads to indifference and silence from established scientists. This “why bother?” response then becomes fodder for the pseudophysicist to claim that the academy is too stuffy to understand his work, or even actively censoring it. The truth is less dramatic, though not without its own interest to old-fashioned students of human nature.
(Ahem)
You may already have seen the news about publishers suing the Internet Archive.
As a scientist and teacher, I will not write or peer-review for any journal from these publishers, nor will I use their books in my classroom, because their emotionally immature stunt risks the collective memory of the Internet.
Whether or not the “National Emergency Library” is ultimately a reasonable idea, there are good ways and bad ways to approach the issue, and Hachette, HarperCollins, Wiley and Penguin Random House have chosen a bad one. For two decades, scholars have been asking, “What value do publishers actually add?” Answers vary, but a bitter “not bloody much” is prominent among them. Undermining our social and technical infrastructure in a time of global crisis only gives that view more weight.
Underappreciated
Some time ago, I had one of those odd little thoughts that could be the spark of an essay. But in this particular case, the point I wanted to make felt like it could be made most clearly by demonstration, rather than explication. So, I wrote a concise report on “An Underappreciated Exchange in the Bohr–Einstein Debate.” Judging by the modest splash of positive e-mail that I received after posting it, I think I layered the whimsy and the serious point adequately well.