Thursday, November 16, 2023

China's EV Market Dominance and the Challenges Facing Tesla — Manifold #48


TP Huang is a computer scientist and analyst of global technology development. 

He posts often on X:

The EV tipping point has arrived in China. Even most techology experts do not appreciate the coming huge impacts on global economics, manufacturing, energy transition, etc.


0:00 Introduction 
2:21 How TP Huang became interested in electric vehicles 
6:30 The perception and reality of Chinese products, future of Chinese auto market 
9:24 The impact of Tesla on the Chinese electric vehicle market 
14:41 Buying a car in China 27:05 China dominates with electric vehicle batteries 
30:44 The challenges facing Tesla in China 
40:11 The evolution of smart cars, autonomous vehicles, and self driving 
50:48 LIDAR technology and autonomous driving 
59:08 BYD, China’s energy independence, and power grid 
1:14:04 The downstream impact of China leading in tech and electric vehicles

Audio-only version and transcript: 

See earlier episodes:

TP on the US-China chip war

Taylor Ogan of Snow Bull Capital (Shenzhen) on EVs, LIDAR, manufacturing in China

Thursday, November 09, 2023

Hypersonic Weapons and Missile Defense

Detailed analysis of boost-glide (BGV) and Maneuverable Re-entry Vehicles (MaRV): physics of interception by US SM-2,3 etc.
Hypersonic Weapons: Vulnerability to Missile Defenses and Comparison to MaRVs 
David Wright and Cameron L. Tracy 
Laboratory for Nuclear Security and Policy, Department of Nuclear Science and Engineering, Massachusetts Institute of Technology 
Center for International Security and Cooperation (CISAC), Freeman Spogli Institute for International Studies, Stanford University
As I concluded long ago, current ship-based tech is not effective to defend even against older DF21 MaRV. See, e.g.,

LEO SAR, hypersonics, and the death of the naval surface ship

The study concludes that air launched BGV/MaRVs could attack ships from well over 1000km. Land or ship based launch would allow even greater range. There is currently no defense against such weapons. 

Russia and PRC both have systems of this type.

Defense requires interceptor missile speeds significantly greater than that of MaRV/BGV in terminal phase. 

This is under ideal conditions where sensors function perfectly - it is just kinematics.

Thursday, November 02, 2023

Taylor Ogan, Snow Bull Capital: China's tech frontier, the view from Shenzhen — Manifold #47


I really enjoyed this conversation. Taylor is a very unique investor who relocated his fund to Shenzhen in order to have direct access to information on Chinese tech companies.

Taylor Ogan is Chief Executive Officer of Snow Bull Capital, based in Shenzhen, China. 

Follow him on X @TaylorOgan

Steve and Taylor discuss: 
0:00 Introduction 
1:02 Taylor's background and why he moved his firm to China 
20:43 China post-pandemic and economic dynamism 
33:43 China dominance in electric vehicles; LIDAR 
56:55 Investment research: factory and site visits 
1:06:52 US-China competition - the future of innovation is in China

Audio-only version and transcript: 

Sunday, October 29, 2023

Thursday, October 26, 2023

Paradise Lost - Migdal, Polyakov, and Landau

This is a placeholder for a longer post I hope to expand on in the future, based on this essay: 

Migdal and Polyakov were two of the great Soviet physicists of their generation. Polyakov is on the upper left and Migdal the lower right.

Wikipedia: Migdal, Polyakov

The essay describes their education as young physicists. They were examined by Landau himself at age 15, and by age 19 had written a paper anticipating the Higgs Mechanism and the role of spontaneous symmetry breaking in gauge theory.

Migdal: Khalat was a genius of political intrigue. Being married into Inner Circle of the Soviet System (his wife Valya is the daughter of a legendary Revolution hero), he used all his connections and all the means to achieve his secret goal — assemble the best brains and let them Think Freely. 
On the surface, his pitch to the Party went as follows. “The West is attacking us for anti-Semitism. The best way to counter this slander is to create an Institute, where Jews are accepted, allowed to travel abroad and generally look happy. This can be a very small Institute, by standards of Atomic Project, it will have no secret military research, it will cost you very little, but it will help “Rasryadka” (Détente). These Jews will be so happy, they will tell all their Jewish friends in the West how well they live. And if they won’t –it is after all, us who decide which one goes abroad and which one stays home. They are smart kids, they will figure out which side of the toast is buttered.” 
As I put it, Khalat sold half of his soul to Devil and used the money to save another half. I truly respect him for that, now once I learned what it takes to create a startup and try to protect it against hostile world. 
As many crazy plans before it, this plan really worked. Best brains were assembled in Landau Institute, they were given a chance to happily solve problems without being forced to eat political shit like the whole country and – yes, they sometimes traveled abroad and made friends in the West. 
In a way the plan worked too well — we became so worldly and so free that we could no longer be controlled. And, needless to say, our friends in the West became closer to us that our curators in KGB.
I was in the 1990s generation of American physicists who had to contend on the job market with a stream of great theorists from the former Soviet Union. Both Migdal and Polyakov ended up at Princeton, and there were many others in their wake, closer to my age.

Sunday, October 22, 2023

Abdus Salam and the Pakistan Nuclear Weapons Program

After my conversation with Bharat Karnad about the Indian nuclear arsenal I became curious about Pakistan's nuclear program. 

I came across this historical analysis:

Abdus Salam: A Reappraisal. Part II Salam's Part in the Pakistani Nuclear Weapon Programme
Salam's biographies claim that he was opposed to Pakistan's nuclear weapon programme. This is somewhat strange given that he was the senior Science Advisor to the Pakistan government for at least some of the period between 1972 when the programme was initiated and 1998 when a successful nuclear weapon test was carried out. I look at the evidence for his participation in the programme.

Salam shared the Nobel Prize with Glashow and Weinberg. He is a leading theoretician, although many have questioned what, exactly, was his contribution to the formulation of the electroweak theory of particle physics that Glashow and Weinberg contributed to.

Currently Pakistan's arsenal is ~200 warheads and similar in size to India's. Their largest warhead is estimated to have a yield of ~40kt, compared to ~20kt for the Indians.

What interested me the most was Salam's role in the early stages of the project.

See the paper for more interesting details. Previously I was only aware of Riazuddin through his academic publications, not his weapons work.

I mentioned to Karnad that I had been surprised that some of the Iranin theoreticians assassinated by Israel over the last 10-15 years had quite abstract research interests. They didn't seem the type to be working on bombs - but I suppose you never know! 

Thursday, October 19, 2023

Bharat Karnad: India geostrategy, nuclear arsenal, and assassination of Homi Bhabha, the Oppenheimer of India — Manifold #46


Bharat Karnad is an Emeritus Professor in National Security Studies at the Center for Policy Research in Delhi. He was a member of India's first National Security Advisory Board and has authored several books on nuclear weapons and Indian security. 

Karnad's blog: 

Karnad on the death of Homi Bhabha and of other atomic weapons scientists: 

An excellent documentary film on the life of Indian theoretical physicist Homi Bhabha: 

Steve and Bharat discuss: 

0:00 Introduction 
0:58 Karnad's educational background, nuclear research, journalism career 
26:50 Refocusing India's defense posture from Pakistan to China 
45:21 Why don't India and China have better relations? 
53:33 India's nuclear arsenal 
1:04:31 The mysterious death of Homi Bhabha, India's Oppenheimer 
1:28:50 Land of subjugation, the caste system, and English as the language of Indian elites

Audio-only and transcript: 

Einstein, Yukawa, Wheeler, and Bhabha:

Karnad on the assassination:

Robert Trumbull Crowley, former Deputy Director of Clandestine Operations for the CIA. Recorded conversations (Conversations With The Crow) near the end of his life:

 ".. their head expert was fully capable of building a bomb and we knew what he was up to. He was warned several times but what an arrogant prick that one was. Told our people to fuck off and then made it clear that no one would stop him and India from getting nuclear parity"

Karnad on Manifold:

Wednesday, October 11, 2023

Quantum Hair During Gravitational Collapse (published version in Physical Review D)

This is a follow up to our earlier work on quantum gravitational corrections to the exterior graviton field of a compact object, also known as quantum hair. 

Here we follow the gravitational collapse of a dust ball and show that the quantum hair persists through the formation of a black hole horizon. The detailed calculations are possible due to an effective field theory formulation of quantum gravity in the long wavelength, low spacetime curvature limit.

Tuesday, October 10, 2023

SMPY 65: Help support the SMPY Longitudinal Study

The Study of Mathematically Precocious Youth (SMPY) needs your help to support the Age-65 phase of their unique longitudinal study. 

For decades, co-directed by David Lubinski and Camilla P. Benbow, SMPY has been a beacon of enlightenment, tracking five cohorts comprising over 5,000 remarkably gifted individuals. In doing so, we have unraveled the secrets to nurturing brilliance. However, we are confronted with a disconcerting reality: the effective methods to identify and cultivate intellectual talent are under siege, threatened by political ideology. 

Our 14-minute documentary and the 3-page feature in Nature underscore the dire need to provide our most gifted youths with the educational opportunities they deserve. They are the architects of solutions and the architects of the future itself. 

Here are some compelling longitudinal findings from SMPY's extensive research:
• Prodigies destined for eminent careers can be identified as early as age 13. 
• There is no plateau of ability; even within the top 1%, variations in mathematical, spatial, and verbal abilities profoundly impact educational, occupational, and creative outcomes. 
• The blend of specific abilities, such as mathematical, spatial, and verbal aptitudes, shapes the nature of one's accomplishments and career trajectory.

More information:




Indicate "Please designate this gift to Study of Mathematically Precocious Youth" in the Special Instructions.

Thursday, October 05, 2023

Yasheng Huang: China's Examination System and its impact on Politics, Economy, Innovation — Manifold #45


Yasheng Huang is the Epoch Foundation Professor of Global Economics and Management at the MIT Sloan School of Management. His new book is The Rise and Fall of the EAST: How Exams, Autocracy, Stability, and Technology Brought China Success, and Why They Might Lead to Its Decline. 

Steve and Yasheng discuss: 

0:00 Introduction 
1:11 From Beijing to Harvard in the 1980s 
15:29 Civil service exams and Huang's new book, "The Rise and Fall of the EAST" 
37:14 Two goals: Developing human capital and indoctrination 
48:33 Impact of the exam system 
57:04 China's innovation peak and decline 
1:12:23 Collaboration and relationship with the West 
1:21:31 How will the U.S.-China relationship evolve? 

Audio-only version, and transcript: 

Yasheng Huang at MIT 

Web site: 

Thursday, September 21, 2023

Hacking State 13 - Steve Hsu: Polygenic Embryo Selection, Improving LLMs, & Getting Nearly Cancelled


Alex Murshak is a Michigan State grad working as an AI engineer in Austin TX. This conversation is Episode 13 of his podcast Hacking State.

Episode description:

Steve and I speak about polygenic risk scoring and embryo selection, using AI to predict phenotype from genotype, in-vitro fertilization (IVF), egg freezing, eugenic public policy, addressing Christians' and right-wing traditionalists' concerns over reproductive technology, Superfocus AI's plan to eliminate hallucination in large language models (LLMs) by separating memory from inference, introspection for LLM error correction, and surviving the failed cancellation attempt at MSU.

Huawei and the US-China Chip War — Manifold #44


TP Huang is a computer scientist and analyst of global technology development. He posts often on X: 

Steve and TP discuss: 

0:00 Introduction: TP Huang and semiconductor technology 
5:40 Huawei’s new phone and SoC 
23:19 SMIC 7nm chip production in China: Yield and economics 
28:21 Impact on Qualcomm 
36:08 U.S. sanctions solved the coordination problem for China semiconductor companies 
42:48 5G modem and RF chips: impact on Qualcomm, Broadcom, Apple, etc. 
47:14 5G and Huawei 52:50 Satellite capabilities of Huawei phones 
56:46 Huawei vs Apple and Chinese consumers 
1:01:33 Chip War and AI model training

Thursday, September 07, 2023

Meritocracy, SAT Scores, and Laundering Prestige at Elite Universities — Manifold #43


I discuss 10 key graphs related to meritocracy and university admissions. Predictive power of SATs and other factors in elite admissions decisions. College learning outcomes - what do students learn? The four paths to elite college admission. Laundering prestige at the Ivies. 


Audio Only and Transcript: 

CLA and college learning outcomes

Harvard Veritas: Interview with a recent graduate 

Defining Merit - Human Capital and Harvard University

Chapter markers: 

0:00 Introduction 
1:28 University of California system report and the use of SAT scores admissions 
8:04 Longitudinal study on gifted students and SAT scores (SMPY) 
12:53 Unprecedented data on earnings outcomes and SAT scores 
15:43 How SAT scores and university pedigree influence opportunities at elite firms 
17:35 Non-academic factors fail to predict student success 
20:49 Predicted earnings 
24:24 Measured benefit of Ivy Plus attendance 
28:25 CLA: 13 university study on college learning outcomes 
32:34 Does college education improve generalist skills and critical thinking? 
42:15 The composition of elite universities: 4 paths to admission 
48:12 What happened to meritocracy? 
51:48 Hard versus Soft career tracks 
54:43 Cognitive elite at Ivies vs state flagship universities 
57:11 What happened to Caltech?

Wednesday, August 30, 2023

The World of Yesterday: Steve Hsu on polygenic scores, gene editing, human flourishing


I really enjoyed this long conversation with Dan Schulz, an MSU engineering grad who works in tech. Dan did his homework and we covered a lot of important topics.


(0:00:00) - Intro 
(0:00:33) -  Genomic Prediction 
(0:05:54) - IVF 
(0:12:34) - Phenotypic data 
(0:15:42) - Predicting height 
(0:28:27) - Pleiotropy 
(0:39:14) - Optimism 
(0:45:03) - Gene editing 
(0:48:27) - Super intelligent humans 
(1:01:27) - Regulation 
(1:06:36) - Human values 
(1:17:38) - Should you do IVF? 
(1:26:06) - 23andMe 
(1:29:03) - Jeff Bezos 
(1:34:29) - Richard Feynman 
(1:43:43) - Where are the superstar physicists? 
(1:45:37) - Is physics a good field to get into?

Thursday, August 24, 2023

Aella: Sex Work, Sex Research, and Data Science — Manifold #42


Aella is a sex worker, sex researcher, and data scientist. 

Interviews with ex-prostitutes on the pimp life (Las Vegas) 

An earlier Aella interview with Reason: 

Audio-only and Transcript:

Steve and Aella discuss: 

(00:00) - Introduction 
(01:22) - Aella's background and upbringing 
(12:45) - Aella's experiences as a sex worker and escorting 
(29:52) - Pimp culture 
(38:01) - Seeking Arrangement 
(43:50) - Cheating 
(46:50) - OnlyFans, farming simps 
(51:49) - Incels and sex work 
(56:24) - Porn and Gen-Z 
(01:12:43) - Embryo screening 
(01:21:43) - How far off is IVG?

Thursday, August 10, 2023

AI on your phone? Tim Dettmers on quantization of neural networks — Manifold #41


Tim Dettmers develops computationally efficient methods for deep learning. He is a leader in quantization: coarse graining of large neural networks to increase speed and reduce hardware requirements. 

Tim developed 4-and 8-bit quantizations enabling training and inference with large language models on affordable GPUs and CPUs - i.e., as commonly found in home gaming rigs. 

Tim and Steve discuss: Tim's background and current research program, large language models, quantization and performance, democratization of AI technology, the open source Cambrian explosion in AI, and the future of AI. 

0:00 Introduction and Tim’s background 
18:02 Tim's interest in the efficiency and accessibility of large language models 
38:05 Inference, speed, and the potential for using consumer GPUs for running large language models 
45:55 Model training and the benefits of quantization with QLoRA 
57:14 The future of AI and large language models in the next 3-5 years and beyond

Thursday, July 27, 2023

Paul Huang, the real situation in Taiwan: politics, military, China — Manifold #40


Paul Huang is a journalist and research fellow with the Taiwanese Public Opinion Foundation. He is currently based in Taipei, Taiwan. 

Sample articles: 

Taiwan’s Military Has Flashy American Weapons but No Ammo (in Foreign Policy): 

Taiwan’s  Military Is a Hollow Shell (Foreign Policy): 

Audio-only and transcript:

Steve and Paul discuss: 

0:00 Introduction 
1:44 Paul’s background; the Green Party (DPP) and Blue Party (KMT) in Taiwan 
4:40 How the Taiwanese people view themselves vs mainland Chinese 
15:02 Taiwan taboos: politics and military preparedness 
15:27 Effect of Ukraine conflict on Taiwanese opinion 
29:56 Lack of realistic military planning 
37:20 Is there a political solution to reunification with China? What influence does the U.S. have? 
51:34 The likelihood of peaceful reunification of Taiwan and China 
56:45 Honest views on Taiwanese and U.S. military readiness for a conflict with China

Thursday, July 13, 2023

Richard Hanania & Rob Henderson: The Rise of Wokeness and the Influence of Civil Rights Law — Manifold #39


Richard Hanania, Rob Henderson, and I were scheduled for a June 2023 panel as part of the University of Austin (UATX) Forbidden Courses series. I missed the panel due to travel issues, but we gathered on this podcast to recreate the fun! 


0:00 Introduction 
1:20 The University of Austin and forbidden courses 
17:37 Will woke campus culture change anytime soon? 
29:57 Common people vs elites on affirmative action 
35:42 Why it’s uncomfortable to disagree about affirmative action 
41:22 Fraud and misrepresentation in higher ed 
44:20 The adversity carveout in the Supreme Court affirmative action ruling 
50:10 Standardized testing and elite university admissions 
1:06:18 Divergent views among racial and ethnic groups on affirmative action; radicalized Asian American males 
1:10:00 Differences between East and South Asians in the West 
1:23:03 Class-based preferences and standardized tests 
1:31:57 Rob Henderson’s next move 


Richard Hanania’s new book: 

The Origins of Woke: Civil Rights Law, Corporate America, and the Triumph of Identity Politics 

Richard Hanania’s newsletter: 

The Center for the Study of Partisanship and Ideology: 

Rob Henderson’s newsletter: 

Rob Henderson’s new book: 

Troubled: A Memoir of Foster Care, Family, and Social Class 

Wednesday, July 05, 2023

Quantum Hair in Electrodynamics and Gravity (Eur. Phys. J. Plus)

This is the published version of the arxiv preprint previously discussed here.
We found it interesting that quantum hair can already be found using the familiar Euler-Heisenberg effective action, which results from integrating out the electron in QED. 

The paper also contains a general argument for why solutions to the semiclassical field equations resulting from the effective action (both in gravity and QED) carry more information about the state of the source than in classical physics. 

From the Conclusions: 
The quantum effective actions for both electrodynamics and gravity lead to field equations which couple a compact source (charge current or energy-momentum tensor) to external fields (electromagnetic or graviton field) in a manner which, generically, leads to quantum memory and quantum hair effects. External solutions of the field equations deviate, due to quantum corrections, from the familiar classical forms that satisfy the Gauss law. As a specific consequence, more information about the interior source configuration is encoded in the external field than in the classical theory. 
As specific applications, we considered semiclassical sources (large black hole, macroscopic charge distribution), which allowed us to solve the quantum corrected field equations by expanding around a classical solution. However, fully quantum statements regarding quantum hair are also possible, which do not, for example, require a semiclassical source. In [1–3] it was shown that the quantum state of a compact source (e.g., in an energy eigenstate or superposition thereof) determines certain aspects of the quantum state of its external field. In principle, measurements of the external fields can fully determine the interior state of a black hole.

Friday, June 30, 2023

Richard Sander (UCLA Law) on the Supreme Court Affirmative Action Ruling — Manifold #38


Richard Sander is Jesse Dukeminier Professor at UCLA Law School. AB Harvard, JD, PhD (Economics) Northwestern. 

Steve and Richard discuss the recent Supreme Court ruling in Students For Fair Admissions vs Harvard and UNC. 

Sander has studied the structure and effects of law school admissions policies. He coined the term "Mismatch" to describe negative consequences resulting from large admissions preferences. 

0:00 Introduction 
1:09 Richard Sander’s initial reaction to the Supreme Court ruling 
4:03 How data influenced the court’s decision 
7:58 Overview of the court’s ruling 
11:27 Carve outs in the court’s ruling 
16:59 The litigation landscape 
21:25 Workarounds to race-blind admissions and the UC system 
32:22 Remedies: What will happen with Harvard and UNC now? 
38:02 The landscape of college admissions 
44:47 Effects of the Supreme Court ruling beyond higher education 


SCOTUS decision on Affirmative Action:

Richard Sander on SCOTUS Oral Arguments: Affirmative Action and Discrimination against Asian Americans at Harvard and UNC, Manifold #23

Richard Sander: Affirmative Action, Mismatch Theory, and Academic Freedom, Manifold #6 

Wednesday, June 28, 2023

Embryo Selection: Healthy Babies vs Bad Arguments

Great article by Diana Fleischman, Ives Parr, Jonathan Anomaly, and Laurent Tellier.
Polygenic screening and its discontents 
... But monogenic and chromosomal screening can only address a part of disease risk because most health conditions that afflict people are polygenic, meaning they are not simply caused by one gene or by a chromosomal abnormality. Instead, they are caused by a huge number of small additive effects dispersed throughout the genome. For example, cancer, schizophrenia, and diabetes can be best predicted by models using tens of thousands of genes. 
A polygenic risk score (PRS) looks at a person’s DNA to see how many variants they have associated with a particular disease. Like BRCA1, polygenic risk scores are typically not determinative: “Polygenic screening is not a diagnosis: It is a prediction of relative future risk compared to other people.” In other words, someone with BRCA1 has a higher risk than someone without, and someone with a high breast cancer PRS has a higher risk than someone with a lower breast cancer PRS. But in principle, BRCA1 is just one gene out of thousands contributing to a PRS, with each bit contributing a small part of a total risk estimate. ... 


... Recently, a group of European scientists argued that polygenic screening should not be available to couples because it will lead to stigmatization, exacerbate inequalities, or lead to confusion by parents about how to weigh up information about risks before they decide which embryo to implant. These are indeed challenges, but they are not unique to embryo selection using polygenic scores, and they are not plausible arguments for restricting the autonomy of parents who wish to screen their embryos for polygenic traits. Furthermore, from an ethical perspective, it is unconscionable to deny polygenic screening to families with a history of any disease whose risk can be reduced by this lifesaving technology. 
Many new technologies are initially only available to people with more money, but these first adopters then end up subsidizing research that drives costs down and quality up. Many other medical choices involve complexity or might result in some people being stigmatized, but this is a reason to encourage genetic counseling and to encourage social tolerance. It is not a reason to marginalize, stigmatize, or criminalize IVF mothers and fathers who wish to use the best available science to increase the chances that their children will be healthy and happy.
This is a comment on the article:
1) They don't want to admit that some people are better than others, inherently. Boo hoo. 
2) You put a scorecard of embryos in front of everyone, and everyone has a pretty good ballpark estimate of which are better and which are worse. Nobody is going to pretend equality is true when they are choosing their kids genes. 
3) So bad feels. 
4) Must therefore retard all human progress and cause immense suffering because don't want to deal with bad feels. 
That's the anti-polygenic argument in a nutshell. I don't expect it to be very effective. At best it will cause it to take a bit longer before poor people have access.

Thursday, June 08, 2023

AI Cambrian Explosion: Conversation With Three AI Engineers — Manifold #37


In this episode, Steve talks to three AI engineers from his startup SuperFocus.AI. 

0:00 Introduction 
1:06 The Google memo and open-source AI 
14:41 Sparsification and the size of models: AI on your phone? 
30:16 When will AI take over ordinary decision-making from humans? 
34:50 Rapid advances in AI: a view from inside 
41:28 AI Doomers and Alignment 

Links to earlier episodes on Artificial Intelligence & Large Language Models: 

Oxford Lecture — #35: 

Bing vs. Bard, US-China STEM Competition, and Embryo Screening — #30: 

ChatGPT, LLMs, and AI — #29: 

Thursday, May 25, 2023

David Goldman: US-China competition, AI, Electric Vehicles, and Manufacturing — Manifold #36


David Paul Goldman is an American economic strategist and author, best known for his series of online essays in the Asia Times under the pseudonym Spengler with the first column published January 1, 2000. 

Steve and David discuss: 

0:00 Introduction 
2:22 David’s background in music, finance, and Asia 
16:55 Looking back at the financial crisis 
23:04 Rise of the Chinese economy 
29:44 How Huawei’s strength is tied to China’s economic power 
36:49 Competition in the global electric vehicles market 
38:06 Why David thinks European countries like Germany will become closer with China 
45:29 U.S. manufacturing is falling behind 
52:08 Potential for war and ongoing U.S.-China competition 
1:04:07 Predictions for Taiwan 


David Goldman in Wikipedia: 
Spengler column: 

You Will Be Assimilated: China's Plan to Sino-form the World 

Prisoner’s Dilemma: Avoiding war with China is the most urgent task of our lifetime 

David Goldman articles in Claremont Review:

Wednesday, May 17, 2023

Quantum Hair During Gravitational Collapse

This is a follow up to our earlier work on quantum gravitational corrections to the exterior graviton field of a compact object, also known as quantum hair. Here we follow the gravitational collapse of a dust ball and show that the quantum hair persists through the formation of a black hole horizon.

The detailed calculations are possible due to an effective field theory formulation of quantum gravity in the long wavelength, low spacetime curvature limit.
Quantum Hair During Gravitational Collapse 
X. Calmet, R. Casadio, S. Hsu, F. Kuipers 
We consider quantum gravitational corrections to the Oppenheimer-Snyder metric describing time-dependent dust ball collapse. The interior metric also describes Friedmann-Lemaitre-Robertson-Walker cosmology and our results are interpreted in that context. The exterior corrections are an example of quantum hair, and are shown to persist throughout the collapse. Our results show the quantum hair survives throughout the horizon formation and that the internal state of the resulting black hole is accessible to outside observers.



Thursday, May 11, 2023

Artificial Intelligence & Large Language Models: Oxford Lecture — Manifold #35


This week's episode is based on a lecture I gave to an audience of theoretical physicists at Oxford University. 

Audio-only version, transcript: 


0:00 Introduction 
2:31 Deep Learning and Neural Networks; history and mathematical results 
21:15 Embedding space, word vectors 
31:53 Next word prediction as objective function 
34:08 Attention is all you need 
37:09 Transformer architecture 
44:54 The geometry of thought 
52:57 What can LLMs do? Sparks of AGI 
1:02:41 Hallucination 
1:14:40 SuperFocus testing and examples 
1:18:40 AI landscape, AGI, and the future

Final slide:

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