superposeur

1. An NYT commenter clarifies that the “Second Grade Teacher” of the article’s title is from a family worth $30+ billion. If true, this would seem to be egregious omission of context from the article.

Ok got it, thanks.

I don’t understand the claim that Kolmogorov lower bounds are uncomputable. Three digit strings are unlikely to run as a program so surely 3 is a lower bound on Kolmogorov of the first million digits of pi, no? To tighten bound, one would need to try out every 4-digit program, every 5-digit program, and so on. Either these produce the first million digits of pi or they don’t when the program is run, so each possibility is checkable in finite time, no? There must be something I’m missing here.

Hard agree. Railing against the “mainstream media” is such a cliched and, ironically, uncritical mode of argument.

If this experiment: https://ui.adsabs.harvard.edu/abs/2024arXiv240202618T/abstra... or others like it turn up positive results, MWI is falsified.

There are several layers of structure here.

Indeed, as you say, Decoherence explains why certain bases are special: when a system is in a pointer basis state, it does not continue entangling with environment (or, at least, does so minimally). When a spinning particle enters a Stern-Gerlach apparatus oriented in z-direction, spin-z is the pointer basis of the system during its time in the apparatus. A spin-up or spin-down particle does not entangle with the environment, but spin +x state would quickly entangle with environment, placing environment in a superposition and "branching" the total state vector of all the stuff in the universe.

Quantum Darwinism is just a refinement of this picture in which the "environment" interacting with the system is itself modeled a series of fragments (i.e. all the different photons that bounce off object). It turns out that the information about which pointer basis state the system is in (spin up or spin down) is redundantly encoded in each of these fragments. Hence, intercepting one photon that interacted with system and reveals "spin-up" (because the particle is in upper path) agrees with other photons that also bounce off object.

BUT, of course, due to linearity of unitary time evolution, there is another "branch" in which spin-down was the outcome of the measurement and everyone agrees on spin-down. This is exactly the Everett picture.

Yes, except for the “asymmetrically” part. In other words, Many Worlds.

These debates over the interpretation of Quantum Mechanics (i.e. what ultimately happens when a “measurement” takes place) are important but don’t bear on the effectiveness of quantum computing. Regardless of your favorite interpretation (almost) everyone agrees that quantum computers should work and be able to do things classical computers cannot.

Yes, the MWI is falsifiable. It asserts that objective collapse does not occur, therefore any observation of objective collapse (such as predicted by GRW or Penrose-Diosi) would falsify it.

It doesn’t. Decoherence is the technical step in the Everett picture defining what a “classical branch” even is and explaining how the state vector branches. Every claim that “Decoherence” somehow offers a distinct interpretation to Everett is pure confusion.

Can you believe that This is Spinal Tap, The Sure Thing, Stand by Me, Princess Bride, When Harry Met Sally, Misery, and A Few Good Men were all directed by the same man? What an eclectic set of masterpieces.

The Maple syntax may superficially seem easier but actually leads to more problems in practice. The point of the [ ] is that argument of a function is logically distinct from algebraically grouping terms in an equation. Also, Mathematica is a camel case language since underscore is for pattern recognition, hence the capitalization of function names. Personally, I’ve found every little Mathematica design feature to be incredibly well thought out, logical, and consistently implemented over the whole of the language.

The introduction to Vol 1 of Weinberg’s Quantum Theory of Fields does this really well, albeit briefly. It feels like getting an “insider’s view” of the historical developments.

Ok, to be clear, let’s say I’m dumb and accidentally go with the default (I get the color of the opt out button wrong or something). As if there’s a “publish my private emails to the internet” default-on button in email. Then, I use it to edit a rec letter for student X, with my signature Y. (Yes I know this is dumb and I try changing names when editing but am sure some actual names may slip through.) A few months later the next model is released trained on the data. Student X asks Claude what Y would write in a rec letter about X. Such a button is a “wings stay on / wings fall off” button on a plane.

Everyone seems to be unsurprised by this move, but I’m genuinely shocked. What a shoot your own foot business decision. Google, evil though it be, doesn’t post the text of your gmails in its search results because who would consider using Gmail after that? This is the llm equivalent. Am I missing something?

Yes, totally. Relevant study: https://www.media.mit.edu/publications/your-brain-on-chatgpt...

My path crossed Nguyen many years ago and I can vouch that he is a very smart, nice, ethical, and solid dude who knows his stuff. I’m also a physicist and know enough about the relevant math and physics to evaluate Nguyen v. Weinstein, though I haven’t processed either of their papers deeply. But, fwiw, Tim’s critique is detailed and readable. In particular, what he says about a faulty complexification step makes perfect sense and would spell death for an approach to unification that hinges on detailed accidents of representation theory (as Weinstein’s seems to). To really judge this, I’d have to delve into Weinstein’s baroque-yet-vague theory, which I’m unwilling to do as I’m pretty sure it would be a waste of time.

Great ep.

The problem I’ve always had with over-weighting deathbed advice is that dying people rarely think through the counterfactuals involved. What would actually be the consequence of not working so hard and relentlessly prioritizing personal relationships (as all such advice seems to recommend)? How much worse of a future would result from financial insecurity and lack of career fulfillment? Has the advice giver actually thought through the tradeoffs that lead you to work hard in the first place? Further, dying people’s worlds usually contract to personal relationships only so it makes sense this is the only aspect of life they emphasize.

Agreed, if you look beyond the bro-ey tone of the presentation, it is smart and nontrivial advice he is delivering here. It is so easy to get distracted by complexity (esp with so much competing internet advice). Picking a couple lifts then making the numbers go up on them is effective and underrated.

In any field, what it even means to be good morphs as you go up in skill level. Non mathematicians know only about arithmetic so they often imagine that mathematicians must be really really good at arithmetic. But this isn't so. Likewise, non musicians think what must make a great musician is perfect pitch. But some of the greatest musicians in history didn’t have it while many mediocre ones do. Similarly, non chess players think GMs must be good at calculating zillions of moves in advance, but apparently they only calculate a small set of moves, which somehow are the right ones.

To take an example cited in the article, Einstein was so far up there that it’s nearly impossible for a non physicist to even understand what he was so good at — crude measures like high school grades or “IQ” barely scratch the surface of the skill that he was a genius at.

Now, perfect pitch does modestly correlate with musical ability, mathematicians are better than average at arithmetic, GMs do calculate more moves than the average shmo, and Einstein got much better than average grades (after all he was accepted at ETH). But that’s all, modest correlations.

There is such a thing as talent in music, mathematics, etc. but it isn’t something a psychologist standing outside these domains would ever be able to devise a test for.

Ha ha, first time I’ve seen another reference to this! Back in the day, I got such a kick out of his description that I began imitating it myself, calling it my “David Lynch Special” dish.

It’s worth mentioning that, brilliant as Dirac’s “sea of filled negative energy states” picture was, no one believes that interpretation now. The Dirac equation is better seen as the classical equation of motion for the Grassmann-valued electron field (just as Maxwell’s equations are the classical eom for photon field). There are only positive-energy states (=quantized excitations of the field). I do think popular accounts should begin mentioning this in order not to keep reinforcing the old Dirac sea interpretation.

Truly a vision of dystopia.

Photons.

Yes, because in point of fact this company is the best at what it does — preventing security breaches. The outage — disruptive as it was — was not a breach. This elemental fact is lost amidst all the knee jerk HN hate, but goes a long way toward explaining why the stock only took a modest hit.

Sorry to break it to the hard-sciencers

Believe me, you aren't "breaking" anything to anyone. If you could solve the secret of happiness (your example), no amount of money would be too small.

The issue isn't whether social science would be good to figure out. Definitely it would, to the extent there is actually a "thing" to figure out, which may be true and may not; i.e., "what makes people happy" may be so contingent and/or so ineluctably open to interpretation that it makes no sense as a rigorizable concept. (There is nothing wrong with unrigorous concepts, btw, these have been fruitfully explored by the poets and philosophers and therapists.)

Ok, so even granting that there is a stable, rigorizable "truth" for the social sciences to discover, the issue is whether the methods and analyses as they have been practiced are effective or even could be tweaked to be effective. Clearly, they aren't. And not just a few bad apple studies, but seemingly the whole darn lot.

I mean, a psych experiment will never have an N comparable to a particle physics experiment or be able to reach the 5-sigma threshold for discovery that now prevails in physics. On the other hand, the object of study for psych is intrinsically interesting since we are people and if something reliable can be gleaned then it's certainly worth money. My concern is that "bigger, better" (as you say) would have to include millions of people across cultures and times, tracking longitudinally, with randomization and controls. (Again, more complexity requires more statistics, not less.). Is this practical? Maybe ...

it's much easier to conduct controlled experiments.

Very true. But this means more statistics and controls are necessary to get solid result from a social science experiment then a particle physics experiment, no? Clearly, this is practically impossible, but there you go.

Yes, the devil always seems to be in the details in psychology experiments. Were the experimenters giving subtle cues to the child, and was this simply a test at how deftly the child picked up these cues? What was the exact wording of the “deal” offered to the child and would a wording change alter the results? Was the experiment conducted at a time of food scarcity or abundance? What were the prevailing cultural norms of how a child “ought” to behave? Would the results change if average child age was 6 months older or younger when experiment was conducted? What was in the drinking water and the air and the paint at the testing site? (With strong claims in the literature that all these are correlated with measures such as average population IQ!)

In the face of all these potential confounders, more statistics and controls seem necessary than, say, in a physics collider experiment on electrons (each electron possessing exactly two characteristics, location and spin, and all such electrons behaving identically regardless of location or time). Yet, even in this setting of simplicity and reproducibility, physicists have still found it necessary to establish a stringent, five-sigma threshold for discovery — 3 sigma anomalies come and go. Such a stringent threshold is unthinkable in psychology due to practical considerations. Ergo, it’s hard for to see how psychology can become a reliable empirical science.