Saturday, September 18, 2021

War Nerd on US-China-Taiwan

Highly recommended. Read this article, which will enable you to ignore 99% of mass media and 90% of "expert" commentary on this topic.
... The US/NATO command may be woofing just to get more ships and planes funded, but woofing can go badly wrong. The people you’re woofing at may think you really mean it. That’s what came very close to happening in the 1983 Able Archer NATO exercises. The woofing by Reagan and Thatcher in the leadup to those exercises was so convincing to the Soviet woof-ees that even the moribund USSR came close to responding in real—like nuclear—ways.
That’s how contingency plans, domestic political theatrics, and funding scams can feed into each other and lead to real wars.
Military forces develop contingency plans. That’s part of their job. Some of the plans to fight China are crazy, but some are just plausible enough to be worrying, because somebody might start thinking they could work. 
... What you do with a place like Xinjiang, if you’re a CIA/DoD planner, is file it under “promote insurgency” — meaning “start as many small fires as possible,” rather than “invade and begin a conventional war.”
And in the meantime, you keep working on the real complaints of the Uyghur and other non-Han ethnic groups, so that if you do need to start a conventional war in the Formosa Straits, you can use the Uyghur as a diversion, a sacrifice, by getting them to rise up and be massacred. Since there’s a big Han-Chinese population in Xinjiang, as the map shows, you can hope to stir up the sort of massacre/counter-massacre whipsaw that leaves evil memories for centuries, leading to a permanent weakening of the Chinese state.
This is a nasty strategy, but it’s a standard imperial practice, low-cost — for the empire, not the local population, of course. It costs those people everything, but empires are not sentimental about such things. 
... The Uyghur in Xinjiang would serve the same purpose as the Iraqi Kurds: “straw dogs destined for sacrifice.” If you want to get really cynical, consider that the reprisals they’d face from an enraged Chinese military would be even more useful to the US/NATO side than their doomed insurgency itself.
Atrocity propaganda is very important in 21st c warfare. At the moment, there’s no evidence of real, mass slaughter in Xinjiang, yet we’re already getting propaganda claims about it. Imagine what US/NATO could make out of the bloody aftermath of a doomed insurgency. Well, assuming that US/NATO survived a war with China, a pretty dicey assumption. More likely, CNN, BBC, and NYT would be the first to welcome our new overlords, Kent Brockman style. Those mainstream-media whores aren’t too bright but Lord, they’re agile. 
... Xinjiang, by contrast, can easily be imagined as One Giant Concentration Camp. After all, our leading “expert” on the province has never been there, and neither have his readers.
... The era of naval war based on carrier groups is over. They know that, even if they won’t say it.
If there’s a real war with China, the carriers will wait it out in San Diego harbor. I don’t say Honolulu, because even that wouldn’t be safe enough.
I’m not denigrating the courage or dedication of the crews and officers of USN vessels. At any level below JCOS, most of them are believers. But their belief is increasingly besieged and difficult to sustain, like an Episcopalian at Easter. You just can’t think too long about how cheap and effective antiship missiles are and still be a believer in aircraft carriers. As platforms of gunboat diplomacy against weak powers, they’re OK. 
... The thing is, and it’s weird you even have to say this: China is a big strong country coming out of an era of deep national humiliation and suffering, proud of its new prosperity. China’s success in lifting a desperately poor population into something like prosperity will likely be the biggest story from this era, when the canonical histories get distilled.
A nation hitting this stage is likely to include a lot of people, especially young men, who are itching to show what their country can do. Their patriotic eagerness is no doubt as gullible as most, but it’s real, and if you pay any attention in the online world, you can’t help seeing it.
People who mouth off about China never seem to imagine that anyone in China might hear, because as we are told over and over again, China-is-an-authoritarian-state. The implication is that nobody in China has any of the nationalistic fervor that we take for granted in our own Anglo states.
... Given the history of US/China relations, from the pogroms against Chinese immigrants to the Chinese Exclusion Act of 1882, through the demonization of Chinese mainlanders in the Cold War (which I remember distinctly from elementary school scare movies), the endless attempts to start insurgencies in Tibet, Xinjiang, and Fujian, to the nonstop violence and abuse of Asians in America, you don’t need to find reasons for Chinese people to want a war.
The odd thing is that most of them don’t seem to. That’s a remarkable testimony to the discipline and good sense of the Chinese public…so far. And it’s also, if you’re thinking clearly, a good reason not to keep provoking China in such gross, pointless ways. A population with that level of discipline and unity, matched with zooming prosperity, technical expertise, and pride on emerging from a long nightmare, is not one to woof at.
Of course the plan in the Pentagon is not real war. The plan is to slow China down, trip it up, “wrong-foot it” as they say in the Commonwealth. 
... So what will China do about Taiwan? China could take it right now, if it wanted to pay the price. Everyone knows that, though many fake-news sites have responded with childish, ridiculous gung-ho stories about how “Taiwan Could Win.” 
But will China invade? No. Not right now anyway. It doesn’t need to. The Chinese elite has its own constituencies, like all other polities (including “totalitarian” ones), and has to answer to them as circumstances change. 
So far China has been extraordinarily patient, a lot more patient than we’d be if China was promising to fight to the death for, say, Long Island. But that can change. Because, as I never tire of repeating, the enemy of the moment has constituencies too. And has to answer to them. 
So what happens if the US succeeds in hamstringing China’s economy? Welp, what’s the most reliable distraction a gov’t can find when it wants to unite a hard-pressed population against some distant enemy? 
That’s when China might actually do something about Taiwan. ...
See also Strategic Calculus of a Taiwan Invasion.

Thursday, September 16, 2021

Men Without Women

This short story has it all -- genetic genealogy, ultra high net worth physics quant banker, stripper, cop, marriage, family, New Yorker writer. It's fiction, but based on real characters and stories. 

There is an audio version, read by the author, at the link.
Satellites by Rebecca Curtis (The New Yorker July 5, 2021) 
My husband and Tony were anxiety-ridden workaholics who’d focussed, from a young age, on earning cash. Tony wanted enough for a good life; Conor, enough to feel safe. They were fifty-six years old, though Conor looked forty-five and Tony thirty-five. They were meticulous, but owing to oversights they’d each had five kids by four women. They were two nerds from New Hampshire. ... 
His ancestors, he told me, had founded America. He’d started working at age twelve, as a farmhand, and eventually acquired a Ph.D. in quantum physics from Harvard, then served for decades as the “head quant” at a world-renowned investment bank. But he wasn’t smart enough to be skeptical when go-go dancers said, Don’t worry, I’m on the pill. ... 
After high school, Tony turned down a scholarship to the University of New Hampshire. He wanted to work. He did active duty in the Marines for eight years, then served in the Air National Guard for twenty while working as a cop. Now he collected his police pension and, for fun, drove a delivery truck. 
Conor smiled. By the way, he said, had Tony ever done 23andMe or 
Tony squinted. Ancestry. Sinead bought them kits for his birthday. Why? 
Conor peered up at Jupiter, approaching Saturn for the great conjunction, and the murky dimmer stars. I studied shuttered restaurants. A few bars had created outdoor dining rooms and were busy; the 7-Eleven was dark, but the ever-glowing “Fortune Teller!” sign on the adjacent cottage was lit. 
No reason, Conor said. Had Tony, he asked, opted into his family DNA tree, to see his matches who’d already done Ancestry? Or elected to receive text alerts whenever some new supposed relative signed on? 
Tony walked swiftly. Nah, he said. He’d done Ancestry to make Sinead happy. He shrugged. She’d made their accounts, he said. She probably opted him in; he wasn’t sure. 
When we got home, Tony’s phone had twenty missed calls. 

Men Without Women, Ernest Hemingway 1927. "Hemingway begins to examine the themes that would occupy his later works: the casualties of war, the often uneasy relationship between men and women, ..."

Rebecca Curtis interview
In “Satellites,” your story in the Fiction Issue, a woman and her husband, a retired banker, host the husband’s friend at their Jersey-shore mansion. The woman is a frustrated writer, and, to inspire her, her husband, Conor, asks the friend, Tony, a retired police officer, to tell her cop stories. How would you describe the woman’s views of these two men? 
The narrator is awed by how smart Tony and her husband are, and by how hard they work. She’s impressed that they’ve read so much and educated themselves about so many diverse topics while performing demanding and often unpleasant jobs, and by the fact that they’re two of the most generous, kind people she knows. She appreciates that they’ve maintained lifelong friendships, something that she wishes she’d done herself. She doesn’t agree with all their political ideas. Earlier in her life, she believed that, one, bankers cared about money but not about art, literature, world hunger, etc.; and, two, that anyone who supported Trumpish policies (or who voted for anyone like Trump) must be an ignorant jerk. Meeting her husband (and Tony) punctured those beliefs. 
The narrator views herself as the proverbial grasshopper: someone—possibly frivolous, vapid, and solipsistic—who wants to enjoy her life, sing, dance, make “art,” while working various hip-but-not-very-remunerative jobs to pay rent, never truly planning for winter. Tony and Conor are ants: anxious, alert to the dangers the world can pose, doing difficult (and sneered-upon) jobs diligently so they’ll be protected when scarcity comes. The narrator aspires to be more ant-like while remaining a grasshopper. 
Tony and Conor are, in some ways, obsessed with genetics and lineage—they discuss and bloodlines—but their own families (they each have five children by four women) are somewhat of a disappointment, or even an afterthought, to them. Can you say a little about that tension? 
Conor and Tony suffer because—in several cases—they don’t have the ability to see their children. In the case of divorce, a time-sharing agreement may be in place, but, if the mother has principal custody and won’t permit the father’s visits, what can the father do? Possession sometimes is nine-tenths of the law. Hiring lawyers and going to court to try to force a mother who won’t honor custody agreements to do so requires copious energy, oodles of spare time, and a small fortune. Conor and Tony care deeply about their children, but they’ve lost control—in some cases, of seeing their kids, and, in others, of influencing them. They may feel powerless.

Tuesday, September 14, 2021

PGT-P with Elizabeth Carr and Dr. Serena Chen


This is a discussion of Preimplantation Genetic Testing in IVF with Dr. Serena Chen (IRMS and Rutgers medical school) and Elizabeth Carr (first US IVF baby, fertility patient advocate). 

We mostly focus on polygenic embryo screening, or PGT-P, but at the end I discuss some recent results showing that Genomic Prediction's aneuploidy test (PGT-A, which screens for chromosomal issues, such as trisomy 21) is more accurate than other existing technologies and leads to significantly higher pregnancy success rates. The results, which were obtained independently (not by GP) in a large sample size study, will be presented at the annual American Society of Reproductive Medicine meeting in October. 

This is a video version of the podcast.

Friday, September 10, 2021

Chinese Air Power: Justin Bronk RUSI UK


This is a good overview. Bronk (Research Fellow for Airpower and Technology in the Military Sciences team at Royal United Services Institute, UK) is good, Rupprecht also. (See show notes for links.)

However, both are looking at open source information and someone fluent in Mandarin with a technical background can do even better. 

Just a few notes for now -- I may revisit to add more detailed analysis. 

1. J10 and J20 are world class fighters, largely indigenously designed. J16 is best flanker variant in the world today. 

2. PLAAF missiles (PL12, PL15, cruise missiles, etc.): some argue that PL12 and PL15 are among the best AAM in the world right now. Note use of AESA seeker in individual missiles while IIRC Russians have not incorporated AESA radar in their fighters yet. 

3. WS10 and WS15 engines nearly mature -- WS10 now deployed in single engine J10. 

4. Note remarks about S400 sales to PRC and relatively small gap between PRC SAMs / air defense and Russian systems. 

5. Individual fighter characteristics are becoming less important compared to missile and sensor technology. For example, the low cost JF-17 (co-developed by PRC and Pakistan) is respectable (roughly comparable to early F-16 capabilities) as a plane, but with its block 3 sensor package and PL-12/15 missiles is competitive with much more expensive generation 4+ fighters. The fighter (eventually, drone or UCAV) becomes just a sensor and missile platform...

6. Slightly off-topic: I think the window for utility of stealth is closing fast as radar technology improves. Ubiquitous drones (which can, for example, image stealth opponents from above or behind) and sensor fusion mean that stealth missions over enemy territory against a peer opponent with good SAMs/air defense looks very risky.

The two very obvious and critical technology gaps between PRC and the West were jet engines and semiconductors. It looks like both are on a clear trajectory to close in the next ~5y or so. My guess is that PRC military radar (EM hardware and hardware/software for post-processing), missile technology, and AI/ML are already on par with the US. Sensors, Missiles/Drones, and AI/ML will be the most important technologies for warfare in the coming decades. [1] [2]

With effectively no technology gap between US and PRC the military equation tilts in their favor over coming decades. Once a country has developed the full stack of military technology their costs are better estimated in PPP rather than exchange rate units: local costs such as compensation for engineers, factory workers, etc. predominate. Since the PRC economy is already significantly larger than the US economy in PPP terms, and growing faster, they can afford more (new, advanced) military hardware than we can in the coming decades. Add to this that their focus is concentrated in the Asia-Pacific region, while the US spreads its capability over the entire world, and it seems almost inevitable (barring economic collapse) that the military balance of power in the Asia region will shift in favor of PRC.

Tuesday, September 07, 2021

Kathryn Paige Harden Profile in The New Yorker (Behavior Genetics)

This is a good profile of behavior geneticist Paige Harden (UT Austin professor of psychology, former student of Eric Turkheimer), with a balanced discussion of polygenic prediction of cognitive traits and the culture war context in which it (unfortunately) exists.
Can Progressives Be Convinced That Genetics Matters? 
The behavior geneticist Kathryn Paige Harden is waging a two-front campaign: on her left are those who assume that genes are irrelevant, on her right those who insist that they’re everything. 
Gideon Lewis-Kraus
Gideon Lewis-Kraus is a talented writer who also wrote a very nice article on the NYTimes / Slate Star Codex hysteria last summer.

Some references related to the New Yorker profile:
1. The paper Harden was attacked for sharing while a visiting scholar at the Russell Sage Foundation: Game Over: Genomic Prediction of Social Mobility 

2. Harden's paper on polygenic scores and mathematics progression in high school: Genomic prediction of student flow through high school math curriculum 

3. Vox article; Turkheimer and Harden drawn into debate including Charles Murray and Sam Harris: Scientific Consensus on Cognitive Ability?

A recent talk by Harden, based on her forthcoming book:

Regarding polygenic prediction of complex traits 

I first met Eric Turkheimer in person (we had corresponded online prior to that) at the Behavior Genetics Association annual meeting in 2012, which was back to back with the International Conference on Quantitative Genetics, both held in Edinburgh that year (photos and slides [1] [2] [3]). I was completely new to the field but they allowed me to give a keynote presentation (if memory serves, together with Peter Visscher). Harden may have been at the meeting but I don't recall whether we met. 

At the time, people were still doing underpowered candidate gene studies (there were many talks on this at BGA although fewer at ICQG) and struggling to understand GCTA (Visscher group's work showing one can estimate heritability from modestly large GWAS datasets, results consistent with earlier twins and adoption work). Consequently a theoretical physicist talking about genomic prediction using AI/ML and a million genomes seemed like an alien time traveler from the future. Indeed, I was.

My talk is largely summarized here:
On the genetic architecture of intelligence and other quantitative traits 
How do genes affect cognitive ability or other human quantitative traits such as height or disease risk? Progress on this challenging question is likely to be significant in the near future. I begin with a brief review of psychometric measurements of intelligence, introducing the idea of a "general factor" or g score. The main results concern the stability, validity (predictive power), and heritability of adult g. The largest component of genetic variance for both height and intelligence is additive (linear), leading to important simplifications in predictive modeling and statistical estimation. Due mainly to the rapidly decreasing cost of genotyping, it is possible that within the coming decade researchers will identify loci which account for a significant fraction of total g variation. In the case of height analogous efforts are well under way. I describe some unpublished results concerning the genetic architecture of height and cognitive ability, which suggest that roughly 10k moderately rare causal variants of mostly negative effect are responsible for normal population variation. Using results from Compressed Sensing (L1-penalized regression), I estimate the statistical power required to characterize both linear and nonlinear models for quantitative traits. The main unknown parameter s (sparsity) is the number of loci which account for the bulk of the genetic variation. The required sample size is of order 100s, or roughly a million in the case of cognitive ability.
The predictions in my 2012 BGA talk and in the 2014 review article above have mostly been validated. Research advances often pass through the following phases of reaction from the scientific community:
1. It's wrong ("genes don't affect intelligence! anyway too complex to figure out... we hope")
2. It's trivial ("ofc with lots of data you can do anything... knew it all along")
3. I did it first ("please cite my important paper on this")
Or, as sometimes attributed to Gandhi: "First they ignore you, then they laugh at you, then they fight you, then you win.”

Technical note

In 2014 I estimated that ~1 million genotype | phenotype pairs would be enough to capture most of the common SNP heritability for height and cognitive ability. This was accomplished for height in 2017. However, the sample size of well-phenotyped individuals is much smaller for cognitive ability, even in 2021, than for height in 2017. For example, in UK Biobank the cognitive test is very brief (~5 minutes IIRC, a dozen or so questions), but it has not even been administered to the full cohort as yet. In the Educational Attainment studies the phenotype EA is only moderately correlated (~0.3 ?) or so with actual cognitive ability.

Hence, although the most recent EA4 results use 3 million individuals [1], and produce a predictor which correlates ~0.4 with actual EA, the statistical power available is still less than what I predicted would be required to train a really good cognitive ability predictor.

In our 2017 height paper, which also briefly discussed bone density and cognitive ability prediction, we built a cognitve ability predictor roughly as powerful as EA3 using only ~100k individuals with the noisy UKB test data. So I remain confident that  ~million individuals with good cognitive scores (e.g., SAT, AFQT, full IQ test) would deliver results far beyond what we currently have available. We also found that our predictor, built using actual (albeit noisy) cognitive scores exhibits less power reduction in within-family (sibling) analyses compared to EA. So there is evidence that (no surprise) EA is more influenced by environmental factors, including so-called genetic nurture effects, than is cognitive ability.

A predictor which captures most of the common SNP heritability for cognitive ability might correlate ~0.5 or 0.6 with actual ability. Applications of this predictor in, e.g., studies of social mobility or educational success or even longevity using existing datasets would be extremely dramatic.

Sunday, September 05, 2021

US debt, dollar-rmb, digital rmb (Gavekal)


I agree with Louis Gave's take on most of the topics discussed. Gavekal manages a China fixed income fund and some other China-focused funds, so he is talking his book. But the arguments stand on their own.

At ~45m, a good discussion of digital RMB and why it will break the technology record for fastest adoption by first 1 billion users. See earlier discussion (Ray Dalio) on de-dollarization and digital RMB here

This is a scary graph from Gave's presentation:

This is another good interview:

Monday, August 30, 2021

Finitism and Physics

New paper on arXiv today.

A brief precis: Gravitational collapse limits the amount of energy present in any space-time region. This in turn limits the precision of any measurement or experimental process that takes place in the region. This implies that the class of models of physics which are discrete and finite (finitistic) cannot be excluded experimentally by any realistic process. Note any digital computer simulation of physical phenomena is a finitistic model.

We conclude that physics (Nature) requires neither infinity nor the continuum. For instance, neither space-time nor the Hilbert space structure of quantum mechanics need be absolutely continuous. This has consequences for the finitist perspective in mathematics -- see excerpt below.
Fundamental Limit on Angular Measurements and Rotations from Quantum Mechanics and General Relativity 
Xavier Calmet, Stephen D.H. Hsu 
We show that the precision of an angular measurement or rotation (e.g., on the orientation of a qubit or spin state) is limited by fundamental constraints arising from quantum mechanics and general relativity (gravitational collapse). The limiting precision is 1/r in Planck units, where r is the physical extent of the (possibly macroscopic) device used to manipulate the spin state. This fundamental limitation means that spin states S1 and S2 cannot be experimentally distinguished from each other if they differ by a sufficiently small rotation. Experiments cannot exclude the possibility that the space of quantum state vectors (i.e., Hilbert space) is fundamentally discrete, rather than continuous. We discuss the implications for finitism: does physics require infinity or a continuum?

From the conclusions:

Our intuitions about the existence and nature of a continuum arise from perceptions of space and time [21]. But the existence of a fundamental Planck length suggests that spacetime may not be a continuum. In that case, our intuitions originate from something (an idealization) that is not actually realized in Nature. 
Quantum mechanics is formulated using continuous structures such as Hilbert space and a smoothly varying wavefunction, incorporating complex numbers of arbitrary precision. However beautiful these structures may be, it is possible that they are idealizations that do not exist in the physical world. 
The introduction of gravity limits the precision necessary to formulate a model of fundamental quantum physics. Indeed, any potential structure smaller than the Planck length or the minimal angle considered here cannot be observed by any device subject to quantum mechanics, general relativity, and causality. Our results suggest that quantum mechanics combined with gravity does not require a continuum, nor any concept of infinity. 
It may come as a surprise to physicists that infinity and the continuum are even today the subject of debate in mathematics and the philosophy of mathematics. Some mathematicians, called finitists, accept only finite mathematical objects and procedures [25]. The fact that physics does not require infinity or a continuum is an important empirical input to the debate over finitism. For example, a finitist might assert (contra the Platonist perspective adopted by many mathematicians) that human brains built from finite arrangements of atoms, and operating under natural laws (physics) that are finitistic, are unlikely to have trustworthy intuitions concerning abstract concepts such as the continuum. These facts about the brain and about physical laws stand in contrast to intuitive assumptions adopted by many mathematicians. For example, Weyl (Das Kontinuum [21, 22]) argues that our intuitions concerning the continuum originate in the mind’s perception of the continuity of space-time. 
There was a concerted effort beginning in the 20th century to place infinity and the continuum on a rigorous foundation using logic and set theory. However, these efforts have not been successful. For example, the standard axioms of Zermelo-Fraenkel (ZFC) set theory applied to infinite sets lead to many counterintuitive results such as the Banach-Tarski Paradox: given any two solid objects, the cut pieces of either one can be reassembled into the other [23]. When examined closely all of the axioms of ZFC (e.g., Axiom of Choice) are intuitively obvious if applied to finite sets, with the exception of the Axiom of Infinity, which admits infinite sets. (Infinite sets are inexhaustible, so application of the Axiom of Choice leads to pathological results.) The Continuum Hypothesis, which proposes that there is no cardinality strictly between that of the integers and reals, has been shown to be independent (neither provable nor disprovable) in ZFC [24]. Finitists assert that this illustrates how little control rigorous mathematics has on even the most fundamental properties of the continuum. 
David Deutsch [26]: The reason why we find it possible to construct, say, electronic calculators, and indeed why we can perform mental arithmetic, cannot be found in mathematics or logic. The reason is that the laws of physics “happen to” permit the existence of physical models for the operations of arithmetic such as addition, subtraction and multiplication. 
This suggests the primacy of physical reality over mathematics, whereas usually the opposite assumption is made. From this perspective, the parts of mathematics which are simply models or abstractions of “real” physical things are most likely to be free of contradiction or misleading intuition. Aspects of mathematics which have no physical analog (e.g., infinite sets, the continuum) are prone to problems in formalization or mechanization. Physics – i.e., models which can be compared to experimental observation, actual “effective procedures” – does not ever require infinity, although it may be of some conceptual convenience. Hence it seems possible, and the finitists believe, that the Axiom of Infinity and its equivalents do not provide a sound foundation for mathematics.
See also 

We experience the physical world directly, so the highest confidence belief we have is in its reality. Mathematics is an invention of our brains, and cannot help but be inspired by the objects we find in the physical world. Our idealizations (such as "infinity") may or may not be well-founded. In fact, mathematics with infinity included may be very sick, as evidenced by Godel's results, or paradoxes in set theory. There is no reason that infinity is needed (as far as we know) to do physics. It is entirely possible that there are only a (large but) finite number of degrees of freedom in the physical universe.
Paul Cohen: I will ascribe to Skolem a view, not explicitly stated by him, that there is a reality to mathematics, but axioms cannot describe it. Indeed one goes further and says that there is no reason to think that any axiom system can adequately describe it.
This "it" (mathematics) that Cohen describes may be the set of idealizations constructed by our brains extrapolating from physical reality. But there is no guarantee that these idealizations have a strong kind of internal consistency and indeed they cannot be adequately described by any axiom system.

Note added
: I should clarify the paragraph from our paper that begins
There was a concerted effort beginning in the 20th century to place infinity and the continuum on a rigorous foundation using logic and set theory. However, these efforts have not been successful. ...
This refers to Hilbert's Program:
In the early 1920s, the German mathematician David Hilbert (1862–1943) put forward a new proposal for the foundation of classical mathematics which has come to be known as Hilbert’s Program. It calls for a formalization of all of mathematics in axiomatic form, together with a proof that this axiomatization of mathematics is consistent. The consistency proof itself was to be carried out using only what Hilbert called “finitary” methods. The special epistemological character of finitary reasoning then yields the required justification of classical mathematics. Although Hilbert proposed his program in this form only in 1921, various facets of it are rooted in foundational work of his going back until around 1900, when he first pointed out the necessity of giving a direct consistency proof of analysis. ...
which Godel showed is not possible to carry out. Note that one of Hilbert's main motivations was the continuum (e.g., construction of the Reals in analysis). What has subsequently been adopted as the rigorous basis for analysis does not satisfy Hilbert's desire for axiomatic, finitary methods. 

The remaining sentences in the paragraph are meant to elucidate aspects of the modern treatment that its critics find unappealing. Of course, judgements of this type are philosophical in nature. 
... For example, the standard axioms of Zermelo-Fraenkel (ZFC) set theory applied to infinite sets lead to many counterintuitive results such as the Banach-Tarski Paradox: given any two solid objects, the cut pieces of either one can be reassembled into the other [23]. When examined closely all of the axioms of ZFC (e.g., Axiom of Choice) are intuitively obvious if applied to finite sets, with the exception of the Axiom of Infinity, which admits infinite sets. (Infinite sets are inexhaustible, so application of the Axiom of Choice leads to pathological results.) The Continuum Hypothesis, which proposes that there is no cardinality strictly between that of the integers and reals, has been shown to be independent (neither provable nor disprovable) in ZFC [24]. Finitists assert that this illustrates how little control rigorous mathematics has on even the most fundamental properties of the continuum. 

Friday, August 27, 2021

Tragedy of Empire / Mostly Sociopaths at the Top


Ecclesiastes 1:9 (KJV) The thing that hath been, it is that which shall be; and that which is done is that which shall be done: and there is no new thing under the sun.

Turn off the TV and close the browser tabs with mainstream media content produced by middlebrow conformists. Watch this video instead and read the links below. 

If you were surprised by events in Afghanistan over the past weeks, ask yourself why you were so out of touch with a reality that has been clear to careful observers for over a decade. Then ask yourself what other things you are dead wrong about...

Ray McGovern is a retired CIA analyst who served as Chief of the Soviet Foreign Policy Branch and preparer/briefer of the President’s Daily Brief. Prior to that he served as an infantry/intelligence officer in the 1960s. 

McGovern wrote Welcome to Vietnam, Mr. President (addressed to President Obama, about Afghanistan) in 2009. 

See also: The Strategic Lessons Unlearned from Vietnam, Iraq, and Afghanistan: Why the Afghan National Security Forces Will Not Hold, and the Implications for the U.S. Army in Afghanistan (Strategic Studies Institute and U.S. Army War College Press 2015) M. Chris Mason  

Related posts:

Tears before the Rain: An Oral History of the Fall of South Vietnam (Afghanistan darkness over Kabul edition) 

Afghanistan is lost (2012)

Podcast version of the interview at top:

More color here from Danny Sjursen, West Point graduate, former US Army Major. Sjursen is a combat veteran who served in Iraq and later as an Army Captain in Afghanistan in command of 4-4 Cavalry B Troop in Kandahar Province from February 2011 to January 2012.

Added from comments:
At the strategic level it has been clear for 10+ years that our resources were better used elsewhere. It was obvious as well that we were not succeeding in nation building or creating a self-sustaining government there. I could go into more detail but you can get it from the links / interviews in the post. 
At the tactical level it should have been obvious that a quick collapse was very possible, just as in S. Vietnam (see earlier oral history post). Off-topic: same thing could happen in Taiwan in event of an actual invasion, but US strategists are clueless. 
Biden deserves credit for staying the course and not kicking the can down the road, as effectively a generation (slight exaggeration) of military and political leaders have done. 
The distortion of the truth by senior leaders in the military and in politics is clear for all to see. Just read what mid-level commanders (e.g., Sjursen) and intel analysts with real familiarity have to say. This was true for Vietnam and Iraq as well. Don't read media reports or listen to what careerist generals (or even worse, politicos) have to say. 
Execution by Biden team was terrible and I think they really believed the corrupt US-puppet Afghan govt could survive for months or even years (i.e., they are really stupid). Thus their exit planning was deeply flawed and events overtook them. However, even a well-planned exit strategy would likely not have avoided similar (but perhaps smaller in magnitude) tragic events like the ones we are seeing now. 
ISS attack on airport was 100% predictable. I don't think most Americans (even "leaders" and "experts") understood ISS and Taliban are mortal enemies, etc. etc. 
There is more of a late-stage imperial decline feel to Afghanistan and Iraq -- use of mercenaries, war profiteering, etc. -- than in Vietnam. All of these wars were tragic and unnecessary, but there really was a Cold War against an existential rival. The "war on terrorism" should always have been executed as a police / intel activity, not one involving hundreds of thousands of US soldiers. 
All of this is (in part) an unavoidable cost of having intellectually weak leaders struggling with difficult problems, while subject to low-information populist democracy (this applies to both parties and even to "highly educated" coastal elites; the latter are also low-information from my perspective). This situation is only going to get worse with time for the US. 
BTW, I could describe an exactly analogous situation in US higher ed (with which I am quite familiar): leaders are intellectually weak, either do not understand or understand and cynically ignore really serious problems, are mainly concerned with their own careers and not the real mission goals, are subject to volatility from external low-information interest groups, etc.

Wednesday, August 25, 2021

Resistance fighter negotiates with former torturer (Afghanistan edition)

The Taliban could easily turn Kabul airport into a trap, creating another Dien Bien Phu for the US. However I suspect they are advised by the Russians and Chinese to grant the Americans a peaceful exit from their 20 year disaster. The negotiations are presumably about the ~$9 billion of frozen assets in the Afghanistan treasury, future sanctions against a Taliban-led government, etc.

CIA Director William Burns held secret meeting in Kabul with Taliban leader Abdul Ghani Baradar (WaPo) 
President Biden dispatched his top spy, a veteran of the Foreign Service and the most decorated diplomat in his Cabinet, amid a frantic effort to evacuate people from Kabul international airport in what Biden has called “one of the largest, most difficult airlifts in history.” 
The CIA declined to comment on the Taliban meeting, but the discussions are likely to have involved an impending Aug. 31 deadline for the U.S. military to conclude its airlift of U.S. citizens and Afghan allies. The Biden administration is under pressure from some allies to keep U.S. forces in the country beyond the end of the month to assist the evacuation of tens of thousands of citizens of the United States and Western countries as well as Afghan allies desperate to escape Taliban rule. 
Britain, France and other U.S. allies have said more time is needed to evacuate their personnel, but a Taliban spokesman warned that the United States would be crossing a “red line” if it kept troops beyond the 31st, which he said would trigger unspecified “consequences.” 
For Baradar, playing the role of counterpart to a CIA director comes with a tinge of irony 11 years after the spy agency arrested him in a joint CIA-Pakistani operation that put him in prison for eight years. ...

There are many more like Baradar. Taliban leader Gholam Ruhani (circled in the photo at top) enjoyed America's tender embrace for many years at Guantanamo.  

I highly recommend The Battle of Algiers for context, as did the Pentagon in 2003 -- to no avail.

The highly dramatic film is about the organization of a guerrilla movement and the illegal methods, such as torture, used by the colonial power to contain it. Algeria succeeded in gaining independence from the French, which Pontecorvo addresses in the film's epilogue.[3] 
The film has been critically acclaimed. Both insurgent groups and state authorities have considered it to be an important commentary on urban guerrilla warfare. 
2003 Pentagon screening 
During 2003, the press reported that United States Department of Defense (the Pentagon) offered a screening of the movie on August 27. The Directorate for Special Operations and Low-Intensity Conflict regarded it as useful for commanders and troops facing similar issues in occupied Iraq.[38] 
A flyer for the screening said: How to win a battle against terrorism and lose the war of ideas. Children shoot soldiers at point-blank range. Women plant bombs in cafes. Soon the entire Arab population builds to a mad fervor. Sound familiar? The French have a plan. It succeeds tactically, but fails strategically. To understand why, come to a rare showing of this film.[39] 
According to the Defense Department official in charge of the screening, "Showing the film offers historical insight into the conduct of French operations in Algeria, and was intended to prompt informative discussion of the challenges faced by the French."[39]
Re: Dien Bien Phu, colonial wars, and Iraq / Afghanistan:
General Georges Catroux presided over a commission of inquiry into the defeat. The commission's final report ("Rapport concernant la conduite des opérations en Indochine sous la direction du général Navarre") concluded: 
"... The event itself was in fact, both in terms of public opinion and of the military conduct of the war and operations, merely the end result of a long process of degradation of a faraway enterprise which, not having the assent of the nation, could not receive from the authorities the energetic impulse, and the size and continuity of efforts, required for success. ..."

Tuesday, August 17, 2021

John Preskill interview by Sean Carroll


This is a great interview of John Preskill by Sean Carroll. 

Both are many worlders. At about 20 minutes John says:
I'm an Everettian... 
I'm comfortable with nothing happening in the world besides unitary evolution ... 
Measurement isn't something fundamentally different. ... 
It seems minimal: you know there's nothing happening but the Schrodinger equation and things are evolving, and if we can reconcile that with what we observe about physics ...

In Ten Years of Quantum Coherence and Decoherence I listed a number of prominent theorists who have expressed some degree of belief in many worlds.

Q1. (largely mathematical): Does the phenomenology of pure state evolution in a closed system (e.g., the universe) reproduce Copenhagen for observers in the system? 
This is a question about dynamical evolution: of the system as a whole, and of various interacting subsystems. It's not a philosophical question and, in my opinion, it is what theorists should focus on first. Although complicated, it is still reasonably well-posed from a mathematical perspective, at least as far as foundational physics questions go. 
I believe the evidence is strong that the answer to #1 is Yes, although the issue of the Born rule lingers (too complicated to discuss here, but see various papers I have written on the topic, along with other people like Deutsch, Zurek, etc.). It is clear from Weinberg's writing that he and I agree that the answer is Yes, modulo the Born rule. 
Define this position to be 
Y* := "Yes, possibly modulo Born" 
There are some theorists who do not agree with Y* (see the survey results above), but they are mostly people who have not thought it through carefully, in my opinion. 
I don't know of any explicit arguments for how Y* fails, and our recent results applying the vN QET strengthen my confidence in Y*. 
I believe (based on published remarks or from my personal interactions) that the following theorists have opinions that are Y* or stronger: Schwinger, DeWitt, Wheeler, Deutsch, Hawking, Feynman, Gell-Mann, Zeh, Hartle, Weinberg, Zurek, Guth, Preskill, Page, Cooper (BCS), Coleman, Misner, Arkani-Hamed, etc. 
But there is a generational issue, with many older (some now deceased!) theorists being reticent about expressing Y* even if they believe it. This is shifting over time and, for example, a poll of younger string theorists or quantum cosmologists would likely find a strong majority expressing Y*. 
[ Social conformity and groupthink are among the obstacles preventing broader understanding of Q1. That is, in part, why I have listed specific high profile individuals as having reached the unconventional but correct view! ]

Saturday, August 14, 2021

Tears before the Rain: An Oral History of the Fall of South Vietnam (Afghanistan darkness over Kabul edition)

Ecclesiastes 1:9 (KJV) The thing that hath been, it is that which shall be; and that which is done is that which shall be done: and there is no new thing under the sun.

If you are following events in Afghanistan you know that the tragedy described below will soon be repeated.

The oral histories collected in this volume are heartbreaking and real, but today the events they describe are all but forgotten.

There was never any reckoning for the crimes and stupidity of the Vietnam war, and there won't be any in the wake of our 20 years in Afghanistan and Iraq. 

Our pathetic leaders and apathetic voters will find plenty of other things to distract them from a serious consideration of what happened. Strike up the band, and salute the flag.

Saigon, US Embassy evacuation, 29 April, 1975:

Kabul, US Embassy evacuation, 15 August, 2021:

From the introduction:

On March 10, 1975, the North Vietnamese Army launched what was to be its final major offensive against South Vietnam, assured that America had lost its will to fight or to finance the independence of South Vietnam. No longer fearful of American intervention, the North Vietnamese were certain that victory and the forceful unification of Vietnam was, after nearly thirty years of conflict, soon to be accomplished. Now the social and military fabric of South Vietnam began to unravel rapidly in many places at the same time. The South suddenly began to lose the war faster than the North could win it. The military forces of the South seemed to be imploding toward Saigon. Cities and provinces were abandoned to the North without a fight. ...Victory for the armies of North Vietnam became, in many strategically important places, a mere matter of marching. 
On March 29, the chaotic and desperate situation was recorded graphically by a CBS news crew that flew aboard a World Airways Boeing 727 to Danang, Vietnam's second largest city, to evacuate refugees. The plane was mobbed by soldiers who shot women and children and each other in a frenzied attempt to scramble aboard the aircraft and escape from the advancing North Vietnamese. As the plane took off with people clinging to the wheels, soldiers on the ground fired at it and a hand grenade blew up under one wing. The plane limped back into Saigon, and that evening a tape of the flight was shown on the CBS Evening News. American television viewers that Easter weekend saw the almost unbelievable horror of an army transformed into murderous rabble and a country thrashing about helplessly in the throes of a violent death. 
... As if to leave no doubt as to America's determination not to intervene again in Vietnam, on the evening of April 23, in a major address at Tulane University, President Gerald Ford announced that the war in Vietnam was "finished as far as America is concerned." The audience of students gave him a standing ovation. 
... On the morning of April 29, Operation Frequent Wind began. The exercise involved the evacuation of American and Vietnamese civilians and military personnel from Tan Son Nhut Airbase and from the American Embassy in Saigon to the Seventh Fleet in the South China Sea. The operation was completed early in the morning of April 30, a few hours before the surrender of the South. When the last Marines were airlifted from the roof of the American Embassy on the morning of April 30, they left behind more than four hundred Vietnamese waiting to be airlifted out of the compound. Throughout the previous day and night those same Vietnamese had been promised again and again that they would never be abandoned by the United States. They watched in silence as the last American helicopter left the roof of the Embassy. Even the final American promise to Vietnam had been broken.
Thomas Polgar was CIA Saigon station chief. This is his last transmission from the embassy before destroying the communications equipment:
“This will be final message from Saigon station,” Mr. Polgar wrote. “It has been a long and hard fight and we have lost. This experience, unique in the history of the United States, does not signal necessarily the demise of the United States as a world power. 
“The severity of the defeat and the circumstances of it, however, would seem to call for a reassessment... Those who fail to learn from history are forced to repeat it. Let us hope that we will not have another Vietnam experience and that we have learned our lesson.”
From his oral history:
... we got word to go, and the ambassador was finally told, ... "No, it's going to be from the roof after all." ...
I didn't have a great emotional attachment to Vietnam like some of my colleagues who really fell in love with the country. But in the end, seeing how it ended, I thought that we really did a miserable job for these people and they would have been much better off if we had never gone there in the first place. 
Our reception on the Blue Ridge [ship] showed the American military at its worst. They started out by searching everybody. I think the ambassador was the only one who was not searched. And in normal peacetime I far outranked the admiral commanding the ship. Nobody objected, though. We were tired. We were pretty placid. And we were a defeated army.
From the epigraph:
Maybe if enough people know what happened to Vietnam, then my memories will never be lost. Maybe then they will be like tears before the rain. So listen. This is very important. This is what I remember. This is what happened to me. These are my tears before the rain. --Duong Gang Son
More from Son's oral history:
As we left Saigon, there was an American soldier standing at the back door of the plane, and he was shooting at the ground. He just kept shooting as we pulled away. And people were still crying inside the plane. I watched the soldier shooting and I wondered what he was shooting at. I think he was just trying to show American power one last time. ... But I can only guess. I don't think he knew what was happening, either. We were all confused. 
Anyway, that was my last look at my country. I saw Vietnam as we flew away and at the back door of the plane was a soldier with a gun shooting at it.


Tears before the Rain: An Oral History of the Fall of South Vietnam by Larry Engelmann 

CBS camera-man Mike Marriott was on the last plane to escape from Danang before it fell in the spring of 1975. The scene was pure chaos: thousands of panic-stricken Vietnamese storming the airliner, soldiers shooting women and children to get aboard first, refugees being trampled to death. Marriott remembers standing at the door of the aft stairway, which was gaping open as the plane took off. "There were five Vietnamese below me on the steps. As the nose of the aircraft came up, because of the force and speed of the aircraft, the Vietnamese began to fall off. One guy managed to hang on for a while, but at about 600 feet he let go and just floated off--just like a skydiver.... What was going through my head was, I've got to survive this, and at the same time, I've got to capture this on film. This is the start of the fall of a country. This country is gone. This is history, right here and now." 

In Tears Before the Rain, a stunning oral history of the fall of South Vietnam, Larry Engelmann has gathered together the testimony of seventy eyewitnesses (both American and Vietnamese) who, like Mike Marriott, capture the feel of history "right here and now." We hear the voices of nurses, pilots, television and print media figures, the American Ambassador Graham Martin, the CIA station chief Thomas Polgar, Vietnamese generals, Amerasian children, even Vietcong and North Vietnamese soldiers. 

Through this extraordinary range of perspectives, we experience first-hand the final weeks before Saigon collapsed, from President Thieu's cataclysmic withdrawal from Pleiku and Kontum, (Colonel Le Khac Ly, put in command of the withdrawal, recalls receiving the order: "I opened my eyes large, large, large. I thought I wasn't hearing clearly") to the last-minute airlift of Americans from the embassy courtyard and roof ("I remember when the bird ascended," says Stuart Herrington, who left on one of the last helicopters, "It banked, and there was the Embassy, the parking lot, the street lights. And the silence"). 

Kabul Update
: right on schedule...

See also Decline of the American Empire: Afghan edition (stay tuned for more).

Wednesday, August 11, 2021

Ten Years of Quantum Coherence and Decoherence

In 2010 I attended a meeting on Quantum Coherence and Decoherence in Benasque, Spain. I've reproduced part of my original blog post on the meeting below.


September 13, 2010  
Here are the slides for my talk today at Benasque: On the origin of probability in quantum mechanics.

At the end I took a poll of the workshop participants and found that over half agreed with the following statement. About 20 percent were strongly opposed. Note this is a meeting on quantum coherence and decoherence, so there are a lot of practical types here, including experimentalists.

It is plausible (but of course unproven) that unitary evolution of a pure state in a closed system can reproduce, for semi-classical creatures inside the system, all of the phenomenology of the Copenhagen interpretation.

As one insightful participant pointed out while I was taking the poll, this is really a mathematical question (if not entirely well-posed), not a physics question.

My recent paper with Roman Buniy: Macroscopic Superpositions in Isolated Systems answers the mathematical question about the dynamics of complex isolated systems under Schrodinger evolution. I had forgotten entirely about the poll in the intervening years (I only came across the blog post by accident recently), but the question persisted... Only in 2020 did I realize that von Neumann's Quantum Ergodic Theorem [1] [2] can be used to prove the result.

Some Benasque photos from 2010 :-)

Added from comments

There are really multiple issues here. Theorists will differ in their opinions on the following questions: 
1. (largely mathematical): Does the phenomenology of pure state evolution in a closed system (e.g., the universe) reproduce Copenhagen for observers in the system? 

This is a question about dynamical evolution: of the system as a whole, and of various interacting subsystems. It's not a philosophical question and, in my opinion, it is what theorists should focus on first. Although complicated, it is still reasonably well-posed from a mathematical perspective, at least as far as foundational physics questions go. 

I believe the evidence is strong that the answer to #1 is Yes, although the issue of the Born rule lingers (too complicated to discuss here, but see various papers I have written on the topic, along with other people like Deutsch, Zurek, etc.). It is clear from Weinberg's writing that he and I agree that the answer is Yes, modulo the Born rule. 

Define this position to be 

Y* := "Yes, possibly modulo Born" 

There are some theorists who do not agree with Y* (see the survey results above), but they are mostly people who have not thought it through carefully, in my opinion. I don't know of any explicit arguments for how Y* fails, and our recent results applying the vN QET strengthen my confidence in Y*. 

I believe (based on published remarks or from my personal interactions) that the following theorists have opinions that are Y* or stronger: Schwinger, DeWitt, Wheeler, Deutsch, Hawking, Feynman, Gell-Mann, Zeh, Hartle, Weinberg, Zurek, Guth, Preskill, Page, Cooper (BCS), Coleman, Misner, Arkani-Hamed, etc. 

But there is a generational issue, with many older (some now deceased!) theorists being reticent about expressing Y* even if they believe it. This is shifting over time and, for example, a poll of younger string theorists or quantum cosmologists would likely find a strong majority expressing Y*. 

[ Social conformity and groupthink are among the obstacles preventing broader understanding of question #1. That is, in part, why I have listed specific high profile individuals as having reached the unconventional but correct view! ]

2. Does this make you confident that the other branches really "exist"? They are "real"? 

Here we get into philosophical questions and you will get a range of answers. 

Many of the Y* theorists (including me) might say:

a. MW is the only logically complete version of QM we have. Copenhagen is not well-defined and inadequate for cosmology (cf density perturbations from inflation and galaxy formation). 

b. I find the existence of the other branches rather extravagant, and I leave open the possibility that there might be some more fundamental modification of QM that changes everything. But I have no idea what that model looks like and there are strong constraints on its properties from Bell, causality, etc. Even a small amount of nonlinearity in the Schrodinger equation leads to lots of causality violation, etc. etc. 
c. I believe that any practical experiment that tries to check whether unitary evolution always holds (i.e., the other branches are *in principle accessible*) will always find it to be the case. In particular this means we will realize and manipulate more and more complicated superposition states over time, and this raises the question of why you and I cannot be in a superposition state right now... 

Note it is possible that only one single decoherent branch of the universal wavefunction is actually realized by Nature ("is real"), and that quantum randomness is an illusion. Hartle and Gell-Mann were sort of hedging this way in some of their last papers on this topic. But remember Gell-Mann even hedged about the reality of quarks before they were directly observed in deep inelastic scattering. 

An aspect to this problem that few theorists appreciate is that a quantum theory of gravity is, at the global level, "timeless": it should be a theory of quantum amplitudes describing an entire spacetime geometry and quantum trajectories of other degrees of freedom on that manifold. As such the many branches of the universal wavefunction are realized "all at once" and concepts like observers must be emergent -- they cannot be fundamental aspects of the theory itself. 

Most of the action in quantum gravity (i.e., strings or loop qg) has been "local" in nature: what are the stringy excitations, compactification, local vacua, etc. The global wavefunction of the universe was already considered by Wheeler and DeWitt but there are still lots of unresolved issues.

Friday, August 06, 2021

Strategic Calculus of a Taiwan Invasion

It seems implausible to me that PRC would risk an invasion of Taiwan in the near term, absent a very strong provocation such as an outright declaration of independence. Mastro's recent article in Foreign Affairs: China's Taiwan Temptation made the case for potential near term conflict, and caused quite a stir among analysts.

My guess is that PRC already has the capability to take Taiwan, but not without significant risk. However, as long as they continue to believe that time is on their side an invasion seems unlikely.

Some comments:

1. PRC would have local air and naval superiority at the beginning of the conflict.

2. I am uncertain as to the details of lift/amphibious assault -- discussed by Goldstein on the panel. This is the main failure mode for PLA.

3. I am uncertain as to Taiwan's will to fight. A quick surrender is not excluded, in my opinion. It seems that most US planners do not understand this.

4. Most westerners fail to understand that this is a frozen civil war, with very strong and emotional commitments from the PRC side. The involvement of Japan in this conflict, given their history of aggression in Asia and previous colonial occupation of Taiwan, could easily get them nuked again (this time with much greater megatonnage). It is unclear whether the present leadership of Japan appreciates this sufficiently.

5. The interests of the average person in the US or Japan (or any Asian country) are best served by working very hard to avoid this conflict.

What is happening across the Taiwan Strait? 
In March, Admiral Philip Davidson, then commander of U.S. forces in the Pacific (INDOPACOM), said in a hearing before Congress that a Chinese attack on Taiwan could take place within six years. His successor, Admiral John Aquilino, agreed that such an attack could occur sooner “than most think.” More recently, however, the chairman of the joint chiefs of staff, General Mark Milley, testified that he believes that China has little intention to take Taiwan by force, and that the capability to do so remains a goal rather than a reality. 
On the other hand, the Chinese military has increased pressure on Taiwan in the past year, flying into the island’s air defense identification zone on numerous occasions. During one day in June, China flew 28 military aircraft toward Taiwan, the largest number in a single day, perhaps in response to G7 and NATO statements on China and Taiwan. 
On July 19, 2021, the National Committee hosted a virtual program with Lyle Goldstein and Oriana Skylar Mastro to discuss China/Taiwan/U.S. military relations. NCUSCR President Stephen Orlins moderated and NCUSCR Director Admiral Dennis Blair offered commentary. 
Lyle J. Goldstein is a research professor in the China Maritime Studies Institute (CMSI) at the Naval War College (NWC) and an affiliate of its new Russia Maritime Studies Institute. Founding director of CMSI and author of dozens of articles on Chinese security policy, he focuses on Chinese undersea warfare. On the broader subject of U.S.-China relations, Dr. Goldstein published Meeting China Halfway in 2015. Over the last several years, he has focused on the North Korea crisis. 
Dr. Goldstein received his bachelor’s degree in government from Harvard, his master’s degree in strategic studies and international economics from the Johns Hopkins University School of Advanced International Studies, and his doctoral degree in politics from Princeton. He speaks Russian as well as Chinese. 
Oriana Skylar Mastro is a center fellow at the Freeman Spogli Institute for International Studies at Stanford University where her research focuses on Chinese military and security policy, Asia-Pacific security issues, war termination, and coercive diplomacy; a senior non-resident fellow at the American Enterprise Institute; an inaugural Wilson Center China fellow; and a fellow in the National Committee’s Public Intellectuals Program. She has published widely, including in Foreign Affairs, International Security, International Studies Review, Journal of Strategic Studies, The Washington Quarterly, The National Interest, Survival, and Asian Security. Her 2019 book, The Costs of Conversation: Obstacles to Peace Talks in Wartime, won the 2020 American Political Science Association International Security Section Best Book by an Untenured Faculty Member. 
Dr. Mastro holds a B.A. in East Asian studies from Stanford University and an M.A. and Ph.D. in politics from Princeton University.

Added from comments
Russia is discussed by the panelists. My guess is that if PRC launched a surprise invasion of TW they would just sit it out. The panelists go so far as to speculate that Russia might collaborate with PRC in the planning of an invasion, and could even provide some geopolitical distraction in support of it. I'm not sure I believe that -- the risk of losing surprise due to information leakage from the Russian side would be a big negative against coordination. 
There would be huge repercussions from nuking Japan (PRC actually has a no first use policy), but the emotional effect of, e.g., seeing a large PLAN ship sunk by a Japanese missile would be very strong. Remember, to PRC it looks like a (very much still disliked) foreign power intervening in an internal Chinese dispute. Sort of like Britain helping the confederacy during our civil war, but much worse. At the beginning of a TW invasion PRC might issue some kind of very strong ultimatum of non-interference to all parties (US, Japan, etc.) and then feel justified if the ultimatum is not obeyed. 
Please don't confuse descriptive analysis with normative analysis. It's important to understand how this looks from the other side, in order to predict their behavior. 
PRC faced down the US on the Korean peninsula when they had NO nuclear deterrent. (The historical record is clear that the US seriously considered using nukes against PRC over Korea and over TW in the past.) This would be a fight over (in their minds) actual Chinese territory, not Korea, and today they have a very credible MAD deterrent.
Re: item #3 above, I would like to see a detailed analysis of Taiwan's senior military leadership and their political leanings. I suspect that among them are many descendants of KMT military officers (like my father and grandfather), who largely still support the KMT political party and not the pro-independence DPP. These officers might lead a military coup in the event of a PRC invasion -- especially if it is a reaction to a DPP proclamation of independence, or other US-backed provocation.


This interview with Professor Alexander Huang of Tamkang University (Taiwan) Graduate Institute of International Affairs and Strategic Studies addresses the possibility of direct participation by the US and Japan in defense of Taiwan. In my opinion, Huang is realistic and well-calibrated.  

This is a clear explanation of the status quo, with opinion poll results:

Wednesday, August 04, 2021

Glenn Diesen on Geostrategy and Greater Eurasia

This is a good discussion of Eurasian geopolitics, Russia-China relations, decline of US empire, multipolarity, etc. 

Note Diesen, originally from Norway and now a professor there, was previously professor at the Higher School of Economics in Moscow. I find his writing on Russia and Eurasian geostrategy much more realistic than what is produced by most US or European academics and analysts. His latest book:
Europe as the Western Peninsula of Greater Eurasia Geoeconomic Regions in a Multipolar World 
Will the increased economic connectivity across the Eurasian supercontinent transform Europe into the western peninsula of Greater Eurasia? The unipolar era entailed the US organising the two other major economic regions of the world, Europe and Asia, under US leadership. The rise of “the rest”, primarily Asia with China at the centre, has ended the unipolar era and even 500-years of Western dominance. China and Russia are leading efforts to integrate Europe and Asia into one large region. The Greater Eurasian region is constructed with three categories of economic connectivity – strategic industries built on new and disruptive technologies; physical connectivity with bimodal transportation corridors; and financial connectivity with new development banks, trading currencies and payments systems. China strives for geoeconomic leadership by replacing the US leadership position, while Russia endeavours to reposition itself from the dual periphery of Europe and Asia to the centre of a grand Eurasian geoeconomic constellation. Europe, positioned between the trans-Atlantic region and Greater Eurasia, has to adapt to the new international distribution of power to preserve its strategic autonomy.

Bonus: A good discussion of hypersonic missile technology and its strategic implications. See also LEO SAR, hypersonics, and the death of the naval surface ship. Effective ranges of hypersonic weapons that can be launched from land-based mobile TEL, submarine, small naval surface combatant, fighter jet, etc. are now in the thousands of kilometers. Combined with ubiquitous satellite imaging, we have a revolution in military affairs...

Monday, July 26, 2021

Farewell, Big Steve

Steven Weinberg, a giant of theoretical physics, passed on July 23, 2021 -- he was 88 years old. His best known work, for which he received the Nobel prize, proposed the unification of electromagnetic and weak forces, and formed a key component of the Standard Model of particle physics. But his lifetime of work ranged from cosmology to gravitation to quantum field theory to foundations of quantum mechanics. A brief autobiography.
Wikipedia: It is a story widely told that Steven Weinberg, who inherited Schwinger's paneled office in Lyman Laboratory (Harvard Physics department), there found a pair of old shoes, with the implied message, "think you can fill these?"
Indeed, it is true that almost no one on the planet could have filled Schwinger's shoes. But Big Steve did, and more.

Below I've reproduced a post from 2017, Steven Weinberg: What's the matter with quantum mechanics? 

The video of Weinberg's talk is from 2016, when he would have been 83 or so.

In this public lecture Weinberg explains the problems with the two predominant interpretations of quantum mechanics, which he refers to as Instrumentalist (e.g., Copenhagen) and Realist (e.g., Many Worlds). The term "interpretation" may be misleading because what is ultimately at stake is the nature of physical reality. Both interpretations have serious problems, but the problem with Realism (in Weinberg's view, and my own) is not the quantum multiverse, but rather the origin of probability within deterministic Schrodinger evolution. Instrumentalism is, of course, ill-defined nutty mysticism 8-)

Physicists will probably want to watch this at 1.5x or 2x speed. The essential discussion is at roughly 22-40min, so it's only a 10 minute investment of your time. These slides explain in pictures.

See also Weinberg on Quantum Foundations, where I wrote:
It is a shame that very few working physicists, even theoreticians, have thought carefully and deeply about quantum foundations. Perhaps Weinberg's fine summary will stimulate greater awareness of this greatest of all unresolved problems in science.
and quoted Weinberg:
... today there is no interpretation of quantum mechanics that does not have serious flaws. 
Posts on this blog related to the Born Rule, etc., and two of my papers:
The measure problem in many worlds quantum mechanics

On the origin of probability in quantum mechanics

Dynamical theories of wavefunction collapse are necessarily non-linear generalizations of Schrodinger evolution, which lead to problems with locality.

Among those who take the Realist position seriously: Feynman and Gell-Mann, Schwinger, Hawking, and many more.

Thursday, July 22, 2021

Embryo Screening for Polygenic Disease Risk: Recent Advances and Ethical Considerations (Genes 2021 Special Issue)

It is a great honor to co-author a paper with Simon Fishel, the last surviving member of the team that produced the first IVF baby (Louise Brown) in 1978. His mentors and collaborators were Robert Edwards (Nobel Prize 2010) and Patrick Steptoe (passed before 2010). In the photo above, of the very first scientific conference on In Vitro Fertilization (1981), Fishel (far right), Steptoe, and Edwards are in the first row. More on Simon and his experiences as a medical pioneer below. 

This article appears in a Special Issue: Application of Genomic Technology in Disease Outcome Prediction.
Embryo Screening for Polygenic Disease Risk: Recent Advances and Ethical Considerations 
L. Tellier, J. Eccles, L. Lello, N. Treff, S. Fishel, S. Hsu 
Genes 2021, 12(8), 1105 
Machine learning methods applied to large genomic datasets (such as those used in GWAS) have led to the creation of polygenic risk scores (PRSs) that can be used identify individuals who are at highly elevated risk for important disease conditions, such as coronary artery disease (CAD), diabetes, hypertension, breast cancer, and many more. PRSs have been validated in large population groups across multiple continents and are under evaluation for widespread clinical use in adult health. It has been shown that PRSs can be used to identify which of two individuals is at a lower disease risk, even when these two individuals are siblings from a shared family environment. The relative risk reduction (RRR) from choosing an embryo with a lower PRS (with respect to one chosen at random) can be quantified by using these sibling results. New technology for precise embryo genotyping allows more sophisticated preimplantation ranking with better results than the current method of selection that is based on morphology. We review the advances described above and discuss related ethical considerations.
I excerpt from the paper below. 

Some related links: 

Over a million babies are born each year via IVF [1,2]. It is not uncommon for IVF parents to have more than one viable embryo from which to choose, as typical IVF cycles can produce four or five. The embryo that is transferred may become their child, while the others might not be used at all. We refer to this selection problem as the “embryo choice problem”. In the past, selections were made based on criteria such as morphology (i.e., rate of development, symmetry, general appearance) and chromosomal normality as determined by aneuploidy testing. 
Recently, large datasets of human genomes together with health and disease histories have become available to researchers in computational genomics [3]. Statistical methods from machine learning have allowed researchers to build risk predictors (e.g., for specific disease conditions or related quantitative traits, such as height or longevity) that use the genotype alone as input information. Combined with the precision genotyping of embryos, these advances provide significantly more information that can be used for embryo selection to IVF parents. 
In this brief article, we provide an overview of the advances in genotyping and computational genomics that have been applied to embryo selection. We also discuss related ethical issues, although a full discussion of these would require a much longer paper. ...

 Ethical considerations:

For further clarification, we explore a specific scenario involving breast cancer. It is well known that monogenic BRCA1 and BRCA2 variants predispose women to breast cancer, but this population is small—perhaps a few per thousand in the general population. The subset of women who do not carry a BRCA1 or BRCA2 risk variant but are at high polygenic risk is about ten times as large as the BRCA1/2 group. Thus, the majority of breast cancer can be traced to polygenic causes in comparison with commonly tested monogenic variants. 
For BRCA carrier families, preimplantation screening against BRCA is a standard (and largely uncontroversial) recommendation [39]. The new technologies discussed here allow a similar course of action for the much larger set of families with breast cancer history who are not carriers of BRCA1 or BRCA2. They can screen their embryos in favor of a daughter whose breast cancer PRS is in the normal range, avoiding a potentially much higher absolute risk of the condition. 
The main difference between monogenic BRCA screening and the new PRS screening against breast cancer is that the latter technology can help an order of magnitude more families. From an ethical perspective, it would be unconscionable to deny PRS screening to BRCA1/2-negative families with a history of breast cancer. ...


On Simon Fishel's experiences as an IVF pioneer (see here):

Today millions of babies are produced through IVF. In most developed countries roughly 3-5 percent of all births are through IVF, and in Denmark the fraction is about 10 percent! But when the technology was first introduced with the birth of Louise Brown in 1978, the pioneering scientists had to overcome significant resistance. There may be an alternate universe in which IVF was not allowed to develop, and those millions of children were never born. 

Wikipedia: ...During these controversial early years of IVF, Fishel and his colleagues received extensive opposition from critics both outside of and within the medical and scientific communities, including a civil writ for murder.[16] Fishel has since stated that "the whole establishment was outraged" by their early work and that people thought that he was "potentially a mad scientist".[17] 

I predict that within 5 years the use of polygenic risk scores will become common in some health systems (i.e., for adults) and in IVF. Reasonable people will wonder why the technology was ever controversial at all, just as in the case of IVF.

Figure below from our paper. EHS = Embryo Health Score. 

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