Thursday, April 18, 2024

Glenn Luk: China’s economic evolution, GDP, and high speed rail — Manifold #58


Glenn Luk has worked as an investment banker, private equity investor, and startup founder. He has closely analyzed aspects of the Chinese economy, including its GDP and high speed rail system. 

Steve and Glenn discuss: 
(00:00) - Introduction 
(01:21) - Glenn Luk's Background: HK, Taiwan, China 
(07:59) - Evolution of Chinese Companies and Economy 
(14:58) - From Banking to Private Equity and Venture Capital 
(23:08) - Founding a Healthcare Startup and Entrepreneurial Ventures 
(26:35) - China's Development and Economic Policies 
(41:17) - Comparing US and China's Economies and Cultures 
(47:12) - Demographics and Consumer Behavior in China 
(49:09) - China's Economy: Beyond GDP 
(56:34) - High Speed Rail: huge success, or white elephant? 
(01:17:26) - Future of China's Economy 

Glenn Luk on Twitter: 

Glenn on High Speed Rail: 

Munger and Ricardo: 

Audio-only and transcript: 

Friday, April 05, 2024

Replica Wormholes and Quantum Hair

Replica Wormholes and Quantum Hair
Xavier Calmet, Stephen D.H. Hsu 
We discuss recent applications of Euclidean path integrals to the black hole information problem. In calculations with replica wormholes as the next-to-leading order correction to the Gibbons-Hawking saddlepoint, the radiation density matrix approaches a pure state at late times, following the Page curve. We compare unitary evaporation of black holes (in real time), mediated by calculable quantum hair effects, with the replica wormhole results. Both replica wormhole and quantum hair approaches imply that radiation states are macroscopic superpositions of spacetime backgrounds, invalidating firewall and monogamy of entanglement constructions. Importantly, identification of modes inside the horizon with radiation modes (i.e., large scale nonlocality across the horizon) is not required to provide a physical picture of unitary evaporation. Radiation modes can encode the interior information while still remaining independent degrees of freedom.

Wormholes dominate the Gibbons-Hawking saddlepoint of the Euclidean path integral after the Page time. This is because wormholes can connect the interiors of any two black holes i,j. At late times the number of such pairs grows as the dimensionality of the radiation Hilbert space squared. 

The wormholes connect BHs with macroscopically different recoil trajectories. This means the radiation approaches a pure state that is a macroscopic superposition - very similar to what our quantum hair expressions indicate.

Thursday, April 04, 2024

Casey Handmer: Terraform Industries and a Carbon-Neutral Future — Manifold #57


Casey Handmer (PhD Caltech, general relativity) is the founder of Terraform Industries. He is one of the most capable and ambitious geo-engineers on planet Earth! 

Terraform Industries is scaling technology to produce cheap natural gas with sunlight and air. Using solar energy, they extract carbon from the air and synthesize natural gas, all at the same site. 

March 2024: "Terraform completes the end to end demo, successfully producing fossil carbon free pipeline grade natural gas from sunlight and air. We also achieved green hydrogen at <$2.50/kg-H2 and DAC CO2 at <$250/T-CO2, two incredible milestones." 


Casey Handmer’s website: 

Terraform Industries: 

Nerds on Patrol [Episode 3] - Terraform Industries: 

Steve and Casey discuss: 

0:00 Introduction 
00:31 Casey's early life and background, from Australia to Caltech 
07:55 The academic path and transition to tech entrepreneurship 10:40 Terraform Industries 
15:21 Solar costs, efficiency, and global Impact 
24:25 A world powered by Terraform methane 
31:27 The entrepreneurial journey: challenges and insights 
35:01 Investor dynamics and strategic decisions for Terraform 
41:28 The hard Reality of manufacturing and innovation 
44:11 Navigating intellectual property and strategic partnerships 
45:49 The moral and technical challenges of carbon neutrality 
55:48 Looking ahead: Terraform's next milestones and the solar revolution

Transcript and Audio-only version:

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