Wednesday, November 25, 2020

Macroscopic Superposition States in Isolated Quantum Systems

Happy Thanksgiving! :-)
Macroscopic Superposition States in Isolated Quantum Systems   
Roman V. Buniy and Stephen D.H. Hsu 
For any choice of initial state and weak assumptions about the Hamiltonian, large isolated quantum systems undergoing Schrodinger evolution spend most of their time in macroscopic superposition states. The result follows from von Neumann's 1929 Quantum Ergodic Theorem. As a specific example, we consider a box containing a solid ball and some gas molecules. Regardless of the initial state, the system will evolve into a quantum superposition of states with the ball in macroscopically different positions. Thus, despite their seeming fragility, macroscopic superposition states are ubiquitous consequences of quantum evolution. We discuss the connection to many worlds quantum mechanics.
It may come as a surprise to many physicists that Schrodinger evolution in large isolated quantum systems leads generically to macroscopic superposition states. For example, in the familiar Brownian motion setup of a ball interacting with a gas of particles, after sufficient time the system evolves into a superposition state with the ball in macroscopically different locations. We use von Neumann's 1929 Quantum Ergodic Theorem as a tool to deduce this dynamical result. 

The natural state of a complex quantum system is a superposition ("Schrodinger cat state"!), absent mysterious wavefunction collapse, which has yet to be fully defined either in logical terms or explicit dynamics. Indeed wavefunction collapse may not be necessary to explain the phenomenology of quantum mechanics. This is the underappreciated meaning of work on decoherence dating back to Zeh and Everett. See talk slides linked here, or the introduction of this paper.

We also derive some new (sharper) concentration of measure bounds that can be applied to small systems (e.g., fewer than 10 qubits). 

Related posts:

Fun fact: Professor Buniy was a postdoc in my group at Oregon. Before coming to the US for graduate school in theoretical physics he was among the last group of young men to serve in the Soviet Army (Strategic Missile Forces IIRC!)

I suppose he has a document like this one:

Here he is in 2011, working on the null energy condition and instabilities in quantum field theories: 

Monday, November 23, 2020

Bruno Maçães on the election and Trump 2024


Post-election observations from Bruno Maçães. 

TrumpTV? Spectacle over Substance in 21st century American politics? Ivanka 2024? The Meme Industrial Complex?

If Bruno is correct the best we can hope for in the US is managed decline -- which is at least better than unmanaged decline!

Wednesday, November 18, 2020

Polls, Election Predictions, Political Correctness, Bounded Cognition (2020 Edition!)

Some analysis of the crap polling and poor election prediction leading up to Nov 2020. See earlier post (and comments): Election 2020: quant analysis of new party registrations vs actual votes, where I wrote (Oct 14)
I think we should ascribe very high uncertainty to polling results in this election, for a number of reasons including the shy Trump voter effect as well as the sampling corrections applied which depend heavily on assumptions about likely turnout. ... 
This is an unusual election for a number of reasons so it's quite hard to call the outcome. There's also a good chance the results on election night will be heavily contested.
Eric Kaufmann is Professor of Politics at Birkbeck College, University of London.
UnHerd: ... Far from learning from the mistakes of 2016, the polling industry seemed to have got things worse. Whether conducted by private or public firms, at the national or local, presidential or senatorial, levels, polls were off by wide margins. The Five Thirty-Eight final poll of polls put Biden ahead by 8.4 points, but the actual difference in popular vote is likely to be closer to 3-4 points. In some close state races, the error was even greater. 
Why did they get it so wrong? Pollsters typically receive low response rates to calls, which leads them to undercount key demographics. To get around this, they typically weight for key categories like race, education or gender. If they get too few Latinos or whites without degrees, they adjust their numbers to match the actual electorate. But most attitudes vary far more within a group like university graduates, than between graduates and non-graduates. So even if you have the correct share of graduates and non-graduates, you might be selecting the more liberal-minded among them. 
For example, in the 2019 American National Election Study pilot survey, education level predicts less than 1% of the variation in whether a white person voted for Trump in 2016. By contrast, their feelings towards illegal immigrants on a 0-100 thermometer predicts over 30% of the variation. Moreover, immigration views pick out Trump from Clinton voters better within the university-educated white population than among high school-educated whites. Unless pollsters weight for attitudes and psychology – which is tricky because these positions can be caused by candidate support – they miss much of the action. 
Looking at this election’s errors — which seems to have been concentrated among white college graduates — I wonder if political correctness lies at the heart of the problem
... According to a Pew survey on October 9, Trump was leading Biden by 21 points among white non-graduates but trailing him by 26 points among white graduates. Likewise, a Politico/ABC poll on October 11 found that ‘Trump leads by 26 points among white voters without four-year college degrees, but Biden holds a 31-point lead with white college graduates.’ The exit polls, however, show that Trump ran even among white college graduates 49-49, and even had an edge among white female graduates of 50-49! This puts pre-election surveys out by a whopping 26-31 points among white graduates. By contrast, among whites without degrees, the actual tilt in the election was 64-35, a 29-point gap, which the polls basically got right.
See also this excellent podcast interview with Kaufmann: Shy Trump Voters And The Blue Wave That Wasn’t 

Bonus (if you dare): this other podcast from the Federalist: How Serious Is The 2020 Election Fraud?

Added: ‘Shy Trump Voters’ Re-Emerge as Explanation for Pollsters’ Miss
Bloomberg: ... “Shy Trump voters are only part of the equation. The other part is poll deniers,” said Neil Newhouse, a Republican pollster. “Trump spent the last four years beating the crap out of polls, telling people they were fake, and a big proportion of his supporters just said, ‘I’m not participating.’” 
In a survey conducted after Nov. 3, Newhouse found that 19% of people who voted for Trump had kept their support secret from most of their friends. And it’s not that they were on the fence: They gave Trump a 100% approval rating and most said they made up their minds before Labor Day. 
Suburbanites, moderates and college-educated voters — especially women — were more likely to report that they had been ostracized or blocked on social media for their support of Trump. ... 
... University of Arkansas economist Andy Brownback conducted experiments in 2016 that allowed respondents to hide their support for Trump in a list of statements that could be statistically reconstructed. He found people who lived in counties that voted for Clinton were less likely to explicitly state they agreed with Trump. 
“I get a little frustrated with the dismissiveness of social desirability bias among pollsters,” said “I just don’t see a reason you could say this is a total non-issue, especially when one candidate has proven so difficult to poll.”

Tuesday, November 17, 2020

The East Is Red, The Giant Rises

Apologies for my recent inactivity. I've been busy finishing several projects and also distracted by our recent election.

Possibly the biggest global impact of this election is on US-China relations.

It seems likely that Biden will be our next president (although I am interested to see what closer inspection of the election reveals), and based on this I think odds have shifted in favor of a continued rise of the PRC in global economic and military power. I now think that the US lacks the will to counter China's continued rise: their main potential failure mode over the next 20 years is internal, not likely a consequence of external pressure. (Although of course there is still a chance the US and China will blunder into a war, with terrible consequences for the whole world.) 

Note I am not saying the US-China cold war or supply chain decoupling are off, just that the US is unlikely to put sufficient pressure on China to significantly retard its development over the next 20 years. This will have to be re-evaluated in 2024, of course, but we may pass the tipping point.

In 2004 I made some forecasts of where China would be in 2020. These forecasts were met with skepticism then but have mostly been correct. See

Benchmarks in China development: emergence of a middle class

Sustainability of China economic growth

My main assumptions were that the differential in growth rates between China and developed countries would average about 5 percent per year -- e.g. 7% vs 2%, and that China would largely close the technology gap.

A growth differential of +2-3% between now and 2050 would lead to a PRC economy which is about twice as large as the US economy (PPP). In 2004 I expected the PPP and nominal measures of Chinese GDP to narrow (I said over the next ~30 years, so I still have about 15 years for that to happen). If that occurs by 2050 then the PRC economy would be about twice as large as the US economy in nominal terms as well. GDP per capita in China would still be only half that of the US, but a 2-1 total GDP ratio has huge implications for geopolitics, the military balance of power, etc. (Note I am not even factoring in COVID-related impacts on the two economies, which are strongly in favor of PRC.) 

Another metric which should be carefully monitored is the ratio of STEM human capital between the two countries, which will continue to move significantly in China's favor.

I displayed the IMF figures below in my 2004 post on sustainability of Chinese economic growth. I felt that +20y along the trajectories described was realistic for PRC, and I was correct.

It would be interesting to see updated 2020 versions.


See also 

In my earlier post on Beijing I emphasized the issue of scale in China -- massive scale that is evident in the video above. 
I traveled in SE Asia before the 1997 currency / economic crisis. At that time there was plenty of evidence of a bubble in those countries -- unused infrastructure and real estate built on spec, few signs of real technological or productive capability, etc. China had aspects of that 10 years ago, but now it's apparent that earlier infrastructure investment is being put to good use. 
As I walked around Beijing I strained to find things around me -- buildings, solar panels, batteries, cars, high speed trains, electronics, software infrastructure, even airplanes -- that couldn't be sourced in China. Other than a few specific tech stacks that will get serious attention in coming years (e.g., CPUs) I was not able to think of many areas in which China has not caught up technologically. 
See Can the US derail China 2025?
There is a consistent Western cognitive bias concerning China: a severe underestimate of her capabilities and the capabilities of her people. This bias persists and analysts should carefully recalibrate in light of their previous predictions and the actual outcomes. Separate from this bias is an overall lack of knowledge and a willingness to accept lazy generalizations...

Saturday, October 31, 2020

Precision Embryo Genotyping and CRISPR Chromosome Deletions (Genomic Prediction)

This recent Cell paper received a lot of attention as it suggests that CRISPR editing can result in chromosome loss. It was cited in the recent National Academies' report Heritable Human Genome Editing (2020) as an example of unexpected consequences / side-effects from CRISPR.
Allele-Specific Chromosome Removal after Cas9 Cleavage in Human Embryos  
Correction of disease-causing mutations in human embryos holds the potential to reduce the burden of inherited genetic disorders and improve fertility treatments for couples with disease-causing mutations in lieu of embryo selection. Here, we evaluate repair outcomes of a Cas9-induced double-strand break (DSB) introduced on the paternal chromosome at the EYS locus, which carries a frameshift mutation causing blindness. We show that the most common repair outcome is microhomology-mediated end joining, which occurs during the first cell cycle in the zygote, leading to embryos with non-mosaic restoration of the reading frame. Notably, about half of the breaks remain unrepaired, resulting in an undetectable paternal allele and, after mitosis, loss of one or both chromosomal arms. Correspondingly, Cas9 off-target cleavage results in chromosomal losses and hemizygous indels because of cleavage of both alleles. These results demonstrate the ability to manipulate chromosome content and reveal significant challenges for mutation correction in human embryos. 
BioRxiv preprint 

My Genomic Prediction colleagues Jia Xu, Diego Marin, and Nathan Treff are co-authors of the paper. GP's precision embryo genotyping capabilities were necessary to determine that a paternal chromosome is sometimes deleted in the embryo due to CRISPR. In GP's standard embryo testing process both parents are genotyped as well as the embryo. The parental genotypes are used to error correct the embryo genotype: DNA amplification starting from just a few biopsied cells introduces noise, but it can be removed. GP can determine whether specific alleles from a parent are present in the embryo. Detection of the deletion of an entire chunk of chromosome would be fairly straightforward.

Thursday, October 29, 2020

Othram helps solve cold case: killer of Siobhan McGuinness (age 5) identified after 46 years

Othram, a DNA forensics company I co-founded, has helped to solve another cold case. 

Montana Girl, 5, Was Abducted Near Home and Found Dead in Drain — and Killer ID'd 46 Years Later 
For 46 years, the family of Siobhan McGuinness waited to find out who killed the spunky 5-year-old back in 1974 
On a frigid February afternoon in 1974, Siobhan McGuinness was walking the short distance home from a friend’s house in Missoula, Montana, when she vanished. Two days later, the 5-year-old’s body was found in a snow-covered drain culvert near the exit for Turah on I-90, just outside the city limits. She had been sexually assaulted. She also sustained trauma to her head and stab wounds to her chest, according to the FBI. 
Detectives at the time searched tirelessly for the little girl’s killer, but came up empty. The case went cold for decades. 
On Monday, authorities announced that after 46 years, the Missoula County Sheriff’s Office Cold Case Squad, detectives from the Missoula Police Department and others had finally identified the man who took the life of the spunky child who was always smiling. Richard William Davis was 32 when he was traveling through the area at the time of Siobhan’s murder, Missoula Police Chief Jason White said at a press conference on Monday. ... 
Using DNA left behind at the crime scene, specialists at private technology company Othram Inc. were able to create a genealogical profile of the suspect, which led them to Davis, the company says in a press release.

See Othram: the future of DNA forensics

The existing FBI standard (CODIS) for DNA identification uses only 20 markers (STRs -- previously only 13 loci were used!). By contrast, genome wide sequencing can reliably call millions of genetic variants. 

For the first time, the cost curves for these two methods have crossed: modern sequencing costs no more than extracting CODIS markers using the now ~30 year old technology. 

What can you do with millions of genetic markers? 

1. Determine relatedness of two individuals with high precision. This allows detectives to immediately identify a relative (ranging from distant cousin to sibling or parent) of the source of the DNA sample, simply by scanning through large DNA databases. ...

If you have contacts in law enforcement, please alert them to the potential of this new technology.

Sunday, October 25, 2020

David Goldman (Spengler): China's Plan to Sino-Form the World

The latest from the always entertaining David Goldman, who writes (wrote?) the Spengler column at Asia Times.

In the lecture below, Goldman summarizes the main themes of his new book You Will Be Assimilated: China’s Plan to Sino-Form the World.


In this next interview (on the China-Iran deal of summer 2020) Goldman drops his guard a bit and waxes poetic with anti-Chinese rhetoric, as he discusses Israel, Iran, and China.

He refers to the Chinese (speaking broadly) as philo-semitic, but then jokes that this means anti-semites who like jews! In light of that remark I wonder how one should characterize Goldman's views on China and the Chinese: philo-sinic or just plain anti-Chinese?

Saturday, October 24, 2020

Composite Polygenic Risk Score predicts longevity

The paper below (senior author at Johns Hopkins University) builds a composite polygenic risk score for mortality (longevity). Outliers (top vs bottom 5%) differ by about 5 years in life expectancy. 

I expect longevity prediction to improve considerably with more and better data to analyze. See also Live Long and Prosper: Genetic Architecture of Complex Traits and Disease Risk Predictors:
We found that genetic risks are largely uncorrelated for different conditions. This suggests that there can exist individuals with, e.g., low risk simultaneously in each of multiple conditions, for essentially any combination of conditions. There is no trade-off required between different disease risks ... One could speculate that a lucky individual with exceptionally low risk across multiple conditions might have an unusually long life expectancy.

If I read the graph below correctly, in their late 70s a positive outlier (male) has ~90% chance of surviving (not sure of timescale, might be next few years? See comments), whereas for a negative outlier the odds are only ~75%.
Combined Utility of 25 Disease and Risk Factor Polygenic Risk Scores for Stratifying Risk of All-Cause Mortality 
Allison Meisner, Prosenjit Kundu, Yan Dora Zhang, Lauren V. Lan, Sungwon Kim, Disha Ghandwani, Parichoy Pal Choudhury, Sonja I. Berndt, Neal D. Freedman, Montserrat Garcia-Closas, Nilanjan Chatterjee 
The American Journal of Human Genetics doi: 10.1016/j.ajhg.2020.07.002 
While genome-wide association studies have identified susceptibility variants for numerous traits, their combined utility for predicting broad measures of health, such as mortality, remains poorly understood. We used data from the UK Biobank to combine polygenic risk scores (PRS) for 13 diseases and 12 mortality risk factors into sex-specific composite PRS (cPRS). These cPRS were moderately associated with all-cause mortality in independent data: the estimated hazard ratios per standard deviation were 1.10 (95% confidence interval: 1.05, 1.16) and 1.15 (1.10, 1.19) for women and men, respectively. Differences in life expectancy between the top and bottom 5% of the cPRS were estimated to be 4.79 (1.76, 7.81) years and 6.75 (4.16, 9.35) years for women and men, respectively. These associations were substantially attenuated after adjusting for non-genetic mortality risk factors measured at study entry. The cPRS may be useful in counseling younger individuals at higher genetic risk of mortality on modification of non-genetic factors.

Thursday, October 22, 2020

Replications of Height Genomic Prediction: Harvard, Stanford, 23andMe

These are two replications of our 2017 height prediction results (also recently validated using sibling data) that I neglected to blog about previously.

1. Senior author Liang is in the Deptartments of Epidemiology and Biostatistics at Harvard.
Efficient cross-trait penalized regression increases prediction accuracy in large cohorts using secondary phenotypes 
Wonil Chung, Jun Chen, Constance Turman, Sara Lindstrom, Zhaozhong Zhu, Po-Ru Loh, Peter Kraft and Liming Liang 
Nature Communications volume 10, Article number: 569 (2019) 
We introduce cross-trait penalized regression (CTPR), a powerful and practical approach for multi-trait polygenic risk prediction in large cohorts. Specifically, we propose a novel cross-trait penalty function with the Lasso and the minimax concave penalty (MCP) to incorporate the shared genetic effects across multiple traits for large-sample GWAS data. Our approach extracts information from the secondary traits that is beneficial for predicting the primary trait based on individual-level genotypes and/or summary statistics. Our novel implementation of a parallel computing algorithm makes it feasible to apply our method to biobank-scale GWAS data. We illustrate our method using large-scale GWAS data (~1M SNPs) from the UK Biobank (N = 456,837). We show that our multi-trait method outperforms the recently proposed multi-trait analysis of GWAS (MTAG) for predictive performance. The prediction accuracy for height by the aid of BMI improves from R2 = 35.8% (MTAG) to 42.5% (MCP + CTPR) or 42.8% (Lasso + CTPR) with UK Biobank data.

2. This is a 2019 Stanford paper. Tibshirani and Hastie are famous researchers in statistics and machine learning. Figure is from their paper.

A Fast and Flexible Algorithm for Solving the Lasso in Large-scale and Ultrahigh-dimensional Problems 
Junyang Qian, Wenfei Du, Yosuke Tanigawa, Matthew Aguirre, Robert Tibshirani, Manuel A. Rivas, Trevor Hastie 
1Department of Statistics, Stanford University 2Department of Biomedical Data Science, Stanford University 
Since its first proposal in statistics (Tibshirani, 1996), the lasso has been an effective method for simultaneous variable selection and estimation. A number of packages have been developed to solve the lasso efficiently. However as large datasets become more prevalent, many algorithms are constrained by efficiency or memory bounds. In this paper, we propose a meta algorithm batch screening iterative lasso (BASIL) that can take advantage of any existing lasso solver and build a scalable lasso solution for large datasets. We also introduce snpnet, an R package that implements the proposed algorithm on top of glmnet (Friedman et al., 2010a) for large-scale single nucleotide polymorphism (SNP) datasets that are widely studied in genetics. We demonstrate results on a large genotype-phenotype dataset from the UK Biobank, where we achieve state-of-the-art heritability estimation on quantitative and qualitative traits including height, body mass index, asthma and high cholesterol.

The very first validation I heard about was soon after we posted our paper (2018 IIRC): I visited 23andMe to give a talk about genomic prediction and one of the PhD researchers there said that they had reproduced our results, presumably using their own data. At a meeting later in the day, one of the VPs from the business side who had missed my talk in the morning was shocked when I mentioned few cm accuracy for height. He turned to one of the 23andMe scientists in the room and exclaimed 

I thought WE were the best in the world at this stuff!?

Saturday, October 17, 2020

Down the Rabbit Hole: Mark Lane, the Zapruder film, and the JFK Conspiracy

Putting these here for future reference. From comments:
At minimum the evidence is strong for a CIA JFK coverup -- see last video, for example. It doesn't mean they did it, ofc. Johnson pressured Warren to lead the commission with the argument that if the public became convinced the Soviets/Cubans were behind it WW3 would result. This could have affected CIA actions post-Dallas as well. But I suspect something more sinister on the part of certain elements of CIA, and there is tons of evidence to that effect leaking out over the years. 
I enjoy listening to Mark Lane speak even if he turns out to be incorrect in some or many of his allegations. I think he destroys Buckley in their debate: Lane the Rationalist and Buckley a good example of motivated or biased reasoning. 
I've followed Spygate for 4 years now, with the media covering it up and FBI/CIA refusing to produce documents, Barr probably acting to protect the institutions, FISA court obviously corrupt, etc. The JFK matter has a very familiar feel to it. [ Should add the Epstein matter, which unfolded in plain sight over 20y, as another example. ]
Mark Lane, at the peak of his powers, discusses the Warren Commission report with William F. Buckley (1966):


 Mark Lane, near the end of his life:


Astonishing 2014 claims about the Zapruder film in CIA hands in the days after Dallas: the creation of two different briefing boards, one seen by CIA director John McCone, the other given to the Warren Commission. The interview is remarkable.


Horne and Brugioni strike me as very credible. CIA NPIC's main activity was interpreting U2 spy plane photographs, and had some of the most advanced photographic technology of the era. They were a logical choice to have a first look at the Zapruder film, but Brugioni did not learn until decades later that the CIA modified the film (removing certain frames, esp. near #313 which shows Kennedy's head exploding) and only gave a full briefing to McCone while witholding information from the Warren Commission. 
While serving as chief analyst of military records at the Assassination Records Review Board in 1997, Douglas Horne discovered that the Zapruder Film was examined by the CIA's National Photographic Interpretation Center two days after the assassination of President Kennedy. 
In this film, Horne interviews legendary NPIC photo interpreter Dino Brugioni, who speaks for the first time about another NPIC examination of the film the day after the assassination. Brugioni didn't know about the second examination and believes the Zapruder Film in the archives today is not the film he saw the day after the assassination.

Bonus: Interview with son of E. Howard Hunt (CIA, convicted Watergate Plumber), including audio of Hunt's confession. Note link to Cord Meyer, also see Mary Meyer 1964 execution in Georgetown...

James Jesus Angleton -- "A Wilderness of Mirrors"

Note Added in response to a question in the comments:
I suggest you invest an hour or two in 
1. Brugioni interview: establishes that a conspiracy at the highest level of CIA to alter the film evidence was in place within ~24h of the shooting. Hard to explain unless there was very strong motivation already... bureaucracies usually can't react that fast when *surprised* by events. 
2. Interview with Hunt's son, concerning his deathbed confession of being aware of (and playing a minor role in) the assassination conspiracy. Hunt is a well-known CIA figure who was involved in lots of covert ops including Watergate. You don't have to accept this as fully credible of course, but you can't say that conspiracy didn't happen because otherwise information would have leaked out. It may very well have leaked out! But few pay attention because of the groupthink against "conspiracy theory" (this term was literally invented and promulgated by CIA to discourage public attention to what it was doing during the Cold War).   
I would say I am very confident of an active cover up post assasination, less confident of a CIA role in the killing. 
Other facts that have leaked out (now confirmed by official documents and the official CIA historian) include the fact that CIA was very closely monitoring Oswald starting in 1959 and that his file was closely held by none other than CIA prince of darkness James Jesus Angleton. Now look into the unsolved killing of Angleton's friend Mary Meyer (who was having an affair with JFK when he was shot) in 1964 and you are off to the races... Their common friend Ben Bradlee (WaPo editor of Watergate fame) wrote in his memoirs of catching Angleton, having broken into Meyer's house, with her diary... 
BTW, over the years it was wrongly reported that RFK did NOT believe in a conspiracy against his brother. The evidence is pretty convincing now that he always believed in a conspiracy but didn't admit it in public.

Wednesday, October 14, 2020

Election 2020: quant analysis of new party registrations vs actual votes

I think we should ascribe very high uncertainty to polling results in this election, for a number of reasons including the shy Trump voter effect as well as the sampling corrections applied which depend heavily on assumptions about likely turnout. 

Graphs below are from a JP Morgan quant analysis of changes in number of registered voters by party and state, and the correlation with actual votes in subsequent election. Of course it is possible that negative covid impact has largely counteracted the effect discussed below (which is an integrated effect over the last 4 years) -- i.e., Trump was in a strong position at the beginning of 2020 but has declined since then. 

This is an unusual election for a number of reasons so it's quite hard to call the outcome. There's also a good chance the results on election night will be heavily contested.

The author of this analysis is Marko Kolanovic, Global Head of Macro Quantitative and Derivatives Strategy at J.P. Morgan. He graduated from New York University with a PhD in theoretical high-energy physics.

Anyone with high conviction about the election is welcome to post their analysis in the comments.

Sunday, October 11, 2020

US and China: A New Cold War (video interview with Lanxin Xiang)


This is an excellent discussion of the US-China geopolitical situation with Professor Lanxin Xiang. Xiang was trained at SAIS (JHU PhD), and currently holds an academic position in Geneva while directing a research institute in Shanghai.

He has a uniquely deep understanding of both Western and Chinese perspectives on globalization, economic development, US-China competition. 

Interestingly, he recently translated Skidelsky's biography of Keynes.

Two related articles in Asia Times by the Brazilian journalist Pepe Escobar:

Bonus: Bill Owens interview. See comments about Huawei at ~50m.


Wikipedia: William A. Owens (born May 8, 1940) is a retired admiral of the United States Navy and who served as Vice Chairman of the Joint Chiefs of Staff from 1994 to 1996.[1][2] Since leaving the military in 1996, he served as an executive or as a member of the board of directors of various companies, including Nortel Networks Corporation.

Sunday, October 04, 2020

Othram Helps Solve 1974 Cold Case: Carla Walker Murder

Othram, a DNA forensics company I co-founded, has solved another cold case. 

Carla Walker of Fort Worth TX was tortured, raped, and murdered in 1974. Finally the killer has been identified and arrested.

This was an open and high profile case just a few months ago. See this April 2020 episode of The DNA of Murder (Oxygen channel), hosted by Paul Holes, the detective who caught the Golden State Killer.

Who Killed Carla Walker? In 1974, 17-year-old Carla Walker’s reported abduction out of the arms of her boyfriend sent a Texas town on a massive manhunt. She was discovered murdered in a culvert three days later. Paul Holes interviews the only witness, Carla’s boyfriend. 
Walker and her boyfriend, Western Hills High School football quarterback Rodney McCoy, attended a Valentine’s dance on Feb. 16, 1974. After the dance, they met up with friends and then stopped by a Fort Worth bowling alley. 
McCoy has always maintained that a man approached the couple while they were sitting inside his car at the bowling alley parking lot and pointed a gun at him. He was beaten unconscious, and when he awoke, he found his cheerleader girlfriend missing.


See Othram: the future of DNA forensics

The existing FBI standard (CODIS) for DNA identification uses only 20 markers (STRs -- previously only 13 loci were used!). By contrast, genome wide sequencing can reliably call millions of genetic variants. 

For the first time, the cost curves for these two methods have crossed: modern sequencing costs no more than extracting CODIS markers using the now ~30 year old technology. 

What can you do with millions of genetic markers? 

1. Determine relatedness of two individuals with high precision. This allows detectives to immediately identify a relative (ranging from distant cousin to sibling or parent) of the source of the DNA sample, simply by scanning through large DNA databases. ...

If you have contacts in law enforcement, please alert them to the potential of this new technology.

Genomic Prediction and Embryo Selection (video panel discussion)


This is a recent panel discussion on genomic prediction, and applications in IVF and health systems (e.g., early screening of high risk individuals for breast cancer, heart disease). 

Jamie Metzl and Simon Fishel are my co-panelists. Metzl is the author of the best seller Hacking Darwin: Genetic Engineering and the Future of Humanity. Fishel was part of the team that produced the first IVF baby in 1978, and has been a leader in IVF research ever since. 

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 risks scores will become common in some health systems and in IVF. Reasonable people will wonder why the technology was ever controversial at all, just as in the case of IVF.

Previous discussion: Sibling Validation of Polygenic Risk Scores and Complex Trait Prediction (Nature Scientific Reports)

Monday, September 28, 2020

Feynman on AI

Thanks to a reader for sending the video to me. The first clip is of Feynman discussing AI, taken from the longer 1985 lecture in the second video.

There is not much to disagree with in his remarks on AI. He was remarkably well calibrated and would not have been very surprised by what has happened in the following 35 years, except that he did not anticipate (at least, does not explicitly predict) the success that neural nets and deep learning would have for the problem that he describes several times as "pattern recognition" (face recognition, fingerprint recognition, gait recognition). Feynman was well aware of early work on neural nets, through his colleague John Hopfield.  [1] [2] [3]

I was at Caltech in 1985 and this is Feynman as I remember him. To me, still a teen ager, he seemed ancient. But his mind was marvelously active! As you can see from the talk he was following the fields of AI and computation rather closely. Of course, he and other Manhattan project physicists were present at the creation. They had to use crude early contraptions for mechanical calculation in bomb design computations. Thus, the habit of reducing a complex problem (whether in physics or machine learning) to primitive operations was second nature. Already for kids of my generation it was not second nature -- we grew up with early "home computers" like the Apple II and Commodore, so there was a black box magic aspect already to programming in high level languages. Machine language was useful for speeding up video games, but not everyone learned it. The problem is even worse today: children first encounter computers as phones or tablets that already seem like magic. The highly advanced nature of these devices discourages them from trying to grasp the underlying first principles.  

If I am not mistaken the t-shirt he is wearing is from the startup Thinking Machines, which built early parallel supercomputers.

Just three years later he was gone. The finely tuned neural connections in his brain -- which allowed him to reason with such acuity and communicate with such clarity still in 1985 -- were lost forever.

Monday, September 21, 2020

Foreign Observers of US Empire

Four recommended discussions, with perspectives largely absent from US media and establishment sources. 

1. US, Russia, China, Iran: Geopolitics and Realpolitik, discussed by a former UK diplomat, a professor at Tehran University, and a Brazilian journalist who covers Eurasia, living in Thailand.


2. Carl Zha, Caltech alumnus and China watcher. TikTok, WeChat, Huawei, semiconductors. The insidious role of US intelligence agencies in the tech war. Part 2.


3. Columbia economic historian Adam Tooze: World Order, Then And Now, ChinaTalk Podcast. Among other topics: State Capitalism, or National Socialism? Why Carl Schmitt is widely studied among Chinese intellectuals. The US won the cold war in Europe, but perhaps not in Asia...  More Tooze

4. The New Great Game: Bruno Maçães and diplomat, writer and former National Security Adviser Shivshankar Menon discuss Asia’s search for a constructive new equilibrium in the wake of growing tensions between China and its neighbours.


Bonus! Energy, Geopolitics, And The New Map: A Book Talk With Daniel Yergin.


Manhattan Institute: 

The shale revolution brought about not only an American competitive advantage in the global oil and gas market, but also an entirely new geopolitical dynamic. Energy is the bedrock of every industrial economy, and even minor shifts in production and prices have had resounding impacts on international diplomacy. 

Today, the global energy landscape differs drastically from a decade ago. The U.S. now leads the world in oil production thanks to fracking, and the world is reacting. But even as Russia pivots to China, and Middle Eastern producers try to recalibrate, every oil-producing country faces the same questions about the future of energy: Will renewable energy reign? And how will international relationships fare with this new map? These issues will become even more controversial during the presidential campaigns.

See also Remarks on the Decline of American Empire for earlier discussion of the impact of fracking on geopolitics.

Saturday, September 19, 2020

When Machine Learning Met Genetic Engineering | CogX 2019 (video)


I recently came across this video on YouTube. 

Hard to believe it's been over a year since the conference. 2020 versions of these meetings were all killed by the pandemic.

I'm in London again to give the talk below and attend some meetings, including Founders Forum and their Healthtech event the day before.
CogX: The Festival of AI and Emerging Technology
King's Cross, London, N1C 4BH

When Machine Learning Met Genetic Engineering

3:30 pm Tuesday June 11 Cutting Edge stage


Stephen Hsu
Senior Vice-President for Research and Innovation
Michigan State University

Helen O’Neill
Lecturer in Reproductive and Molecular Genetics

Martin Varsavsky
Executive Chairman
Prelude Fertility

Azeem Azhar (moderator)
Exponential View

Regent's Canal, Camden Town near King's Cross.

CogX speakers reception, Sunday evening:


Commanding heights of global capital:

Sunset, Camden locks:

Tuesday, September 15, 2020

Schrodinger's Cat and the Normaliens

Yesterday I had cause to look something up related to macroscopic superposition states ("Schrodinger cat states") in Serge Haroche's book Exploring the Quantum. Curiosity led me to Haroche's 2012 Nobel Lecture and autobiography, which I found fascinating. 

One wonders how long an elitist, highly meritocratic and undeniably productive system like the French Grandes Ecoles can continue to function in the current political climate. Quel dommage.
... I was fascinated by astronomy and by calculus, the notion of derivatives and simple differential equations which describe so directly and so well the laws of dynamics obeyed by moving bodies. This was the time of the first artificial satellites, the sputniks which orbited the earth and launched the American-Soviet race to the moon. 
I marveled at the fact that I was able, with the elementary calculus I knew, to compute the escape velocity of rockets, the periods of satellites on their orbits and the gravitational field at the surface of all the planets … I understood then that nature obeys mathematical laws, a fact that did not cease to astonish me. I knew, from that time on, that I wanted to be a scientist. For that, I embarked in the strenuous and demanding “classes préparatoires” of the famed Lycée Louis-Le-Grand, one of the preparatory schools which train the best French students for the contest examinations leading to the “Grandes Ecoles.” They are the engineering and academic schools, which since the French Revolution, have formed the scientific elite of France. These were two years of intensive study where I learned a lot of math and of classical physics. I eventually was admitted in 1963 to the Ecole Polytechnique (ranking first in the national examination, to the great pride of my parents) and at the Ecole Normale Supérieure (ENS). I chose to enter the latter because, at that time, it offered a much better opportunity to embark in a scientist career. 
The years as a student at ENS (1963–1967) have left me wonderful memories, contrasting sharply with the strenuous training of the preparatory school. Here, in the middle of the Latin Quarter, I was free to organize my time as I wished, to meet and discuss with students working in all kinds of fields in science or humanities and to enjoy all the distractions and cultural activities Paris has to offer. And I was paid for that, since the “Normaliens” as the ENS students are called, are considered civil servants and receive a generous stipend! These were my formative years as a scientist. Coming so to speak from the physics of the 19th century which was taught in the classes préparatoires, I was immediately thrown into modern physics and the quantum world by the classes of exceptional teachers. Alfred Kastler gave us a lyrical description of the dance of atomic kinetic moments, and gave atoms and photons a near poetic existence. Jean Brossel brought us back to Earth by describing the great experiments thanks to which quantum concepts were established, instilling in us the austere passion for precision. And Claude Cohen-Tannoudji revealed the theory’s formalism to us with extraordinary depth and clarity. I still remember three books I read avidly at the time: Quantum Mechanics by Albert Messiah, where I truly understood the depth and beauty of the quantum theory; Principlesof Nuclear Magnetism by Anatole Abragam, who introduced me to the subtle world of atomic magnetic moments; and Feynman’s Lectures on Physics, which was a revelation.
See also 

Saturday, September 12, 2020

Orwell: 1944, 1984, and Today

George Orwell 1944 Letter foreshadows 1984, and today:
... Already history has in a sense ceased to exist, i.e. there is no such thing as a history of our own times which could be universally accepted, and the exact sciences are endangered as soon as military necessity ceases to keep people up to the mark. Hitler can say that the Jews started the war, and if he survives that will become official history. He can’t say that two and two are five, because for the purposes of, say, ballistics they have to make four. But if the sort of world that I am afraid of arrives, a world of two or three great superstates which are unable to conquer one another, two and two could become five if the fuhrer wished it. That, so far as I can see, is the direction in which we are actually moving ... 
... intellectuals are more totalitarian in outlook than the common people. On the whole the English intelligentsia have opposed Hitler, but only at the price of accepting Stalin. Most of them are perfectly ready for dictatorial methods, secret police, systematic falsification of history etc. so long as they feel that it is on ‘our’ side.
I am sure any reader can provide examples of the following from the "news" or academia or even from a national lab:
there is no such thing as a history of our own times which could be universally accepted  
the exact sciences are endangered  
two and two could become five
dictatorial methods ... systematic falsification of history etc. so long as they feel that it is on ‘our’ side.

Of course, there is nothing new under the sun. It takes only a generation for costly lessons to be entirely forgotten...

Wikipedia: Trofim Denisovich Lysenko ...Soviet agronomist and biologist. Lysenko was a strong proponent of soft inheritance and rejected Mendelian genetics in favor of pseudoscientific ideas termed Lysenkoism.[1][2] In 1940, Lysenko became director of the Institute of Genetics within the USSR's Academy of Sciences, and he used his political influence and power to suppress dissenting opinions and discredit, marginalize, and imprison his critics, elevating his anti-Mendelian theories to state-sanctioned doctrine. 
Soviet scientists who refused to renounce genetics were dismissed from their posts and left destitute. Hundreds if not thousands of others were imprisoned. Several were sentenced to death as enemies of the state, including the botanist Nikolai Vavilov. Scientific dissent from Lysenko's theories of environmentally acquired inheritance was formally outlawed in the Soviet Union in 1948. As a result of Lysenkoism and forced collectivization, 15-30 million Soviet and Chinese citizens starved to death in the Holodomor and the Great Chinese Famine. ...


In 1964, physicist Andrei Sakharov spoke out against Lysenko in the General Assembly of the Academy of Sciences of the USSR: "He is responsible for the shameful backwardness of Soviet biology and of genetics in particular, for the dissemination of pseudo-scientific views, for adventurism, for the degradation of learning, and for the defamation, firing, arrest, even death, of many genuine scientists."

Saturday, September 05, 2020

Adam Tooze: American Power in the Long 20th Century


London Review of Books (LRB) lecture:
The history of American power, as it is commonly written, is a weighty subject, a matter of military and economic heft, of ‘throw-weight’, of resource mobilisation and material culture, of ‘boots on the ground’. In his lecture, Adam Tooze examines an alternative, counterintuitive vision of America, as a power defying gravity. This image gives us a less materialistic, more fantastical and more unstable vision of America’s role in the world.
The Q&A at 1h03min is probably the best (at least most concise) part of the talk. I don't find the Geithner anecdote quite as important / symbolic as Tooze does. Geithner is expressing the point that financial markets and economies are heavily affected by animal spirits, investor confidence, etc. Geithner understands well how much the power of central banks depends on purely psychological multiplier effects.

From a YouTube comment, this outline:
1:10 - Tim Geithner; U.S. Treasury: America had been “defying gravity" 
5:50 - U.S. was the “gravity” of world 
11:07 - U.S. is now also subject to the “gravity” of world 
13:28 - 100 years of 9 historic U.S. events; Overview 
14:44 - Adam Tooze; Historian “Ordering rather than Order, and the Disordering effects of efforts at Ordering.” 
16:28 - Start at the beginning of 1800’s 
17:12 - 1898 U.S. Imperialist power 
17:50 - 1916 U.S. Globalist power 
18:47 - Woodrow Wilson; U.S. President 
22:46 - 1920s Republican domestic priority of Financial Austerity and Tax cuts. 
25:59 - Great American Financial shocks/panics; 1857, 1873, 1893, 1896, 1907, 1920, 1929 26:49 - 1920s Great Depression 
27:18 - 1930s U.S. Hyper militaristic power 
31:51 - World War 2; One World, One War (1942) 
33:48 - Post World War 2, Bretton Woods economic conference. 
36:24 - Marshall Plan not the same as Bretton Woods... 
41:10 - Cold War: Asia 
43:30 - U.S. President Nixon abandons the Gold peg in 1971. Which results in inflation in G7 countries and Switzerland. 
44:10 - Keynesian era 50s to 60s. Start of Neoliberalism or the Paul Volcker shock 1979. 
45:07 - Cold War: Europe 1980s, Reagan & Gorbachev 
47:13 - Concluding phase of the talk 
1:01:56 - Challenges in 2019 and going forward; China and Climate Change 
1:03:20 - Q&A
Also recommended: Tooze on US-China geopolitical competition (August 6 2020 Sinica podcast). This discussion focuses more on the present and future than the past and may be of more interest to readers.

This conversation with Tyler Cowen is excellent, with more focus on Europe.

This is part 3 of a discussion at the Paris School of Economics. Thomas Piketty is on the panel and his remarks are in part 2, following Tooze's presentation in part 1. I recommend part 3 as the most interesting. Topics covered include MMT, inequality, central banks, current sources of systemic risk. Note this discussion took place before the Covid19 pandemic. Tooze mentions individual hedge fund compensation in the hundreds of millions or billions of dollars. Typically in such cases a big chunk of this compensation is really returns from the individual's own net worth which is co-invested with the fund. So it's not directly comparable to other forms of compensation, such as salary or bonus.

Friday, August 28, 2020

PRC ASBM Test in South China Sea


This is an interesting discussion of PRC Anti-Ship Ballistic Missiles (ASBM), including the DF21, DF26, and DF17 systems. You can set the captions to English if necessary. (Google realtime speech to text and translation have improved significantly in the last year or so.)

In response to US activity in the South China Sea and elsewhere, PRC recently conducted a test of DF21 and DF26 in the open ocean. Reportedly, a US "Cobra Ball" RC135S missile intelligence aircraft was present to monitor the activity. 

The YouTube video discusses PRC ASBM capabilities, including 

1. Infrared and radar final targeting
2. Maneuver capability
3. Capability of the missile to receive (ground based) over-the-horizon radar and satellite information while in flight. 

These are the frequent subject of speculation in Western sources: "There is a long kill chain and we are not sure whether it is operational..." etc.

Assuming that PRC ASBM have these capabilities, which seems quite plausible to me, this test was presumably a demonstration for the US, to make sure that our military appreciates the PLARF ability to hit a moving target (e.g., US aircraft carrier) at sea. Once this mutual understanding is in place, FONOPs in the South China Sea become mere theatrics for the dim witted.

See related posts

The Future of the U.S. Aircraft Carrier: Fearsome Warship or Expensive Target? (Heritage panel; video) 

Machine intelligence threatens overpriced aircraft carriers (first principles analysis of final targeting problem)

A2AD fait accompli? (Yaogan satellite surveillance of the western Pacific)

Tuesday, August 25, 2020

The Inheritors and The Grisly Folk: H.G. Wells and William Golding on Neanderthals

Some time ago I posted about The Grisly Folk by H.G. Wells, an essay on Neanderthals and their encounters with modern humans. See also The Neanderthal Problem, about the potential resurrection of early hominids via genomic technology, and the associated ethical problems. 

The Grisly Folk: ... Many and obstinate were the duels and battles these two sorts of men fought for this world in that bleak age of the windy steppes, thirty or forty thousand years ago. The two races were intolerable to each other. They both wanted the eaves and the banks by the rivers where the big flints were got. They fought over the dead mammoths that had been bogged in the marshes, and over the reindeer stags that had been killed in the rutting season. When a human tribe found signs of the grisly folk near their cave and squatting place, they had perforce to track them down and kill them; their own safety and the safety of their little ones was only to be secured by that killing. The Neandertalers thought the little children of men fair game and pleasant eating. ...

William Golding was inspired by Wells to write The Inheritors (his second book, after Lord of the Flies), which is rendered mostly (until the end, at which point the perspective is reversed) from the Neanderthal point of view. Both Wells and Golding assume that Neanderthals were not as cognitively capable as modern humans, but Golding's primitives are peaceful quasi-vegetarians, quite unlike the Grisly Folk of Wells.

The Inheritors 
Golding considered this his finest novel and it is a beautifully realised tale about the last days of the Neanderthal people and our fear of the ‘other’ and the unfamiliar. The action is revealed through the eyes of the Neanderthals whose peaceful world is threatened by the emergence of Homo sapiens. 
The struggle between the simple Neanderthals and the malevolent modern humans ends in helpless despair ... 
From the book jacket: "When the spring came the people - what was left of them - moved back by the old paths from the sea. But this year strange things were happening, terrifying things that had never happened before. Inexplicable sounds and smells; new, unimaginable creatures half glimpsed through the leaves. What the people didn't, and perhaps never would, know, was that the day of their people was already over."

See this episode of the podcast Backlisted for an excellent discussion of the book. 

I am particularly interested in how Golding captures the perspective of pre-humans with limited cognitive abilities. He conveys the strangeness and incomprehensibility of modern humans as perceived by Neanderthals. In this sense, the book is a type of Science Fiction: it describes a first encounter with Aliens of superior capability.

We are approaching the day when modern humans will encounter a new and quasi-alien intelligence: it may be AI, or it may be genetically enhanced versions of ourselves.

On a scientific note, can someone provide an update to this 2013 work: "... high quality genome sequence obtained from the toe of a female Neanderthal who lived in the Altai mountains in Siberia. Interestingly, copy number variation at 16p11.2 is one of the structural variants identified in a recent deCODE study as related to IQ depression"? Here is an interesting follow up paper: Nature 2016 Aug 11; 536(7615): 205–209.



Saturday, August 15, 2020

Othram helps identify murder victim from ~20 cells equivalent DNA sample

Othram, a DNA forensics company I co-founded, continues to solve cold cases around the world. 

Murder victim Rodney Peter Johnson was identified from a sample of only 0.2 nanograms of DNA (equivalent of 20 cells). Mr. Johnson had last been seen in 1987, when he was 25 years old. His body was discovered in 1994 by a fisherman in Lake Stickney, near Everett WA. It was badly decomposed and could not be identified.

The Johnson family has waited decades for closure. Press conference video.

See Othram: the future of DNA forensics

The existing FBI standard (CODIS) for DNA identification uses only 20 markers (STRs -- previously only 13 loci were used!). By contrast, genome wide sequencing can reliably call millions of genetic variants. 

For the first time, the cost curves for these two methods have crossed: modern sequencing costs no more than extracting CODIS markers using the now ~30 year old technology. 

What can you do with millions of genetic markers? 

1. Determine relatedness of two individuals with high precision. This allows detectives to immediately identify a relative (ranging from distant cousin to sibling or parent) of the source of the DNA sample, simply by scanning through large DNA databases. ...

If you have contacts in law enforcement, please alert them to the potential of this new technology.

Cheap Document Camera

I built this using a $35 1080p web camera and a $20 LED lamp I already had in my office. 

I've tested on Google Meet and Zoom, it allows me to display equations and quick sketches to collaborators and students. There are much fancier purpose-built document cameras with similar functionality, but these are mostly sold out on Amazon, due to the increase in remote work and online teaching. The particular web cam I am using (see link above) has a manual focus, in case the software auto-focus is unsatisfactory.

Both Google Meet and Zoom allow to switch from the default internal camera on my laptop to the external web cam (a simple toggle in Settings). The web cam is auto-detected on both Mac OS and Chrome -- I did not have to install any drivers.

The plastic clip I used to attach the web cam to the lamp is from the kitchen (Bed Bath and Beyond). Tape would also work as the web cam is very light.

Here is the rig in action, using Google Meet. I write on the pad and my colleague can see it very clearly.

Wednesday, August 12, 2020

U.S.-China Decoupling: Separating Myth From Reality (Georgetown panel)


This is a good panel on US-China decoupling, from June 2020. I especially recommend the discussion between 1h and 1h30m.

Regarding semiconductors: How fast will SMIC close the gap with TSMC? It's now a huge priority. 

Chip design in China advanced much faster than most US observers expected in the past few years, and I think semiconductor fabrication will also advance quickly in the future. Fabs are huge, complex infrastructure investments, which they tend to do well. (According to Goodrich, 60 fabs under construction right now in China.) I also expect them to be good at fine-tuning the production process, pulling in engineering talent from Taiwan and S. Korea as necessary. The most difficult technology hurdle will be the advanced lithography machines that still depend on US and European intellectual property. 
Georgetown US-China Dialogue 2020 
Wang Tao is a managing director and head of Asia Economic Research at UBS investment bank in Hong Kong. She covers macroeconomic and policy issues in Asia and China. 
Jörg Wuttke is the chief representative in China of BASF, a large German chemical company. He is also the president of the European Union Chamber of Commerce in China. 
Dan Wang is a Beijing-based technology analyst at Gavekal Dragonomics, an economic research firm. His focus is on China's technology progress—especially on semiconductors—as well as the unfolding tech war related to the Committee on Foreign Investment in the United States, export controls, and Huawei. 
Jimmy Goodrich is vice president for global policy at the Semiconductor Industry Association (SIA). In this role, he leads SIA’s global policy team and its research and analysis of foreign semiconductor policies and capabilities. Jimmy is also the executive committee chair of the United States Information Technology Office (USITO) in Beijing, representing SIA in his capacity.

Related: China's eRMB, a blockchain based digital currency linked 1-1 to the yuan, seems to be flying under the radar. In my opinion this has huge possibilities -- in the future, anyone with the app (an eRMB account) can transact in RMB whether they are in Germany or Iran. This development is an inevitable consequence of the US weaponizing SWIFT...  

Ray Dalio Warns of U.S.-China ‘Capital War’ That Would Hit Dollar (Bloomberg)


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