a16z crypto show

By a16z crypto, Robert Hackett, Sonal ChokshiBusiness Entrepreneurship Technology Arts Visual Arts

a16z crypto show episodes

August 13 The 'Useless' Theory Behind Modern SNARKs (ft. Gödel Prize Winner Noam Nisan)
More than 30 years ago, Gödel Prize Winner Noam Nisan helped develop a proof technique that he never expected anyone to use in the real world.
At the center of that breakthrough was the sum-check protocol — an elegant technique that emerged from Noam Nisan’s early work on interactive proofs. At the time, even Nisan assumed ideas like these were far too theoretical to become practical technology. Today, sum-check sits at the heart of some of the fastest modern SNARKs, proof systems that are increasingly important to blockchains and verifiable computation.
In this episode of First Principles, a16z crypto Head of Research Tim Roughgarden and research partner Justin Thaler sit down with Noam Nisan to trace the unlikely journey from theory to infrastructure. They explore how interaction and randomness changed the very definition of a mathematical proof; the deceptively simple “two into one” insight behind sum-check; the rapid sequence of discoveries that culminated in IP = PSPACE; and why Justin believes sum-check may be close to the optimal tool for building practical SNARKs.
But Nisan’s career also tells a broader story about how research responds to technological change. When the web arrived in the 1990s, he deliberately left a field in which he was already a leading researcher to understand a new problem: How do you get independent actors on the internet to cooperate when they have different incentives? That question helped give rise to algorithmic game theory — and, decades later, brought Nisan back to questions around blockchain fees, token economics, and protocol design.
Highlights
0:00 — Intro
1:28 — Noam Nisan and the origins of verifiable computation
2:58 — Why Noam Nisan left complexity theory
7:52 — POPcorn, distributed computing, and early blockchain-like ideas
11:10 — The birth of algorithmic game theory
16:14 — Justin Thaler discovers the sum-check protocol
25:05 — From arithmetization to LFKN
27:06 — The story behind IP = PSPACE
30:40 — Why sum-check matters for modern SNARKs
31:15 — What is a SNARK?
38:52 — The key idea behind sum-check: turning two into one
44:03 — When SNARKs went from theory to practice
46:03 — Why blockchains were the breakthrough use case
50:36 — Noam Nisan’s move into blockchain economics
56:15 — EIP-1559, transaction fees, and efficient blockspace
1:02:07 — From theoretical computer science to real-world systems
1:08:49 — Boiling down the sum-check protocol: Two become one
1:10:58 — Is the sum-check protocol optimal?

About First Principles

First Principles is a series from a16z crypto exploring the foundational ideas behind modern computing, cryptography, and blockchains through conversations with the researchers who developed them — and the people extending those ideas today.

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1 hr 16 min
August 10 How Zero-Knowledge Proofs Were Invented (ft. Co-Inventor and Turing Award Winner Shafi Goldwasser)
How can you prove that something is true without revealing why it is true?

That question gave rise to zero-knowledge proofs, one of the most important breakthroughs in modern cryptography. What began as an attempt to solve a seemingly playful problem — playing poker securely over the telephone — ultimately changed how computer scientists think about proofs, privacy, and verification. In this episode of First Principles, Turing Award–winning cryptographer Shafi Goldwasser joins a16z crypto Head of Research Tim Roughgarden and Research Partner Justin Thaler to tell the origin story of zero-knowledge proofs and interactive proof systems.

Goldwasser recounts how she, Silvio Micali, and Charles Rackoff developed a new kind of proof involving interaction, randomness, and a small probability of error. Their work introduced the idea that a prover could convince a verifier that a statement is true while revealing no additional information. The conversation follows those ideas through some of theoretical computer science’s deepest results, including interactive proofs, IP = PSPACE, probabilistically checkable proofs, the sum-check protocol, and SNARKs.

These concepts now power blockchain rollups, privacy-preserving applications, and systems for verifying computation without repeating all the work. They also explore why breakthrough ideas are often initially rejected, how toy problems can lead to foundational theories, why abstraction and narrative matter in scientific research, and whether AI systems should be required to prove their answers.

Highlights
0:00 — Intro
3:36 — How mental poker inspired zero-knowledge proofs: Proving that something is true without revealing the underlying information
6:30 — The simulation paradigm and the meaning of “zero knowledge”
8:33 — Why the original paper was repeatedly rejected
10:33 — How interactive proofs became more powerful than conventional proofs
13:36 — The road to modern SNARKs
19:02 — Why the sum-check protocol is so useful for verifiable computation
25:31 — Why many so-called “zk proofs” are not actually zero knowledge
34:06 — Why toy examples, playfulness, and narratives can produce deep theory
37:23 — The role of rigor and computational assumptions in cryptography
42:44 — Applying zero-knowledge proofs to law, evidence, and secret software
45:23 — Training AI systems to provide proofs alongside their answers
54:27 — Why genuinely new ideas are often difficult for experts to recognize

About First Principles

First Principles is a special limited series from a16z crypto about the scientific roots of modern computing — especially blockchains — told through rare conversations with the pioneers who helped shape the foundational ideas behind distributed systems, consensus protocols, economics, mechanism design, cryptography, zero knowledge, and more.

People often tell the story of the Bitcoin whitepaper as if it appeared out of nowhere. But the ideas behind Bitcoin — and blockchains more broadly — come from decades of computer science, economics, mathematics, and cryptography. First Principles is a guide to that lineage, as told by the people who helped build it.

Links
Shafi Goldwasser
MIT CSAIL: http://people.csail.mit.edu/shafi/
Simons Institute: https://simons.berkeley.edu/people/shafi-goldwasser

Tim Roughgarden
a16z crypto: https://a16zcrypto.com/team/tim-roughgarden/
Website: https://timroughgarden.org/ "X: https://x.com/Tim_Roughgarden

Justin Thaler
a16z crypto: https://a16zcrypto.com/team/justin-thaler/
Website: https://people.cs.georgetown.edu/jthaler/
X: https://x.com/SuccinctJT

a16z crypto
Subscribe: https://www.youtube.com/@a16zcrypto
Website: https://a16zcrypto.com/
X: https://twitter.com/a16zcrypto
Newsletter: https://a16zcrypto.substack.com/

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58 min
August 01 Marc Andreessen and Chris Dixon: Why America Needs CLARITY
a16z Cofounder and General Partner Marc Andreessen and a16z crypto Founder and Managing Partner Chris Dixon on why the CLARITY ACT matters.
Congress is debating once-in-a-generation market structure legislation that could determine where financial and internet infrastructure gets built. Chris and Marc join host Robert Hackett to discuss why regulatory clarity matters, what the current policy environment has cost the United States, and what is at stake for developers, entrepreneurs, consumers, and the country’s technological leadership.
Marc also looks back at his influential 2014 essay “Why Bitcoin Matters,” when supporting crypto was still a deeply contrarian position, and reflects on how the technology and the political debate around it have evolved since.
The discussion explores the lessons of earlier technology revolutions, the importance of giving builders clear rules, and why crypto policy is ultimately about much more than a single industry. It is about who gets to shape the future of money, markets, and the internet.
Highlights
00:00 Intro
05:31 From crypto subculture to financial infrastructure
08:37 Why crypto needs rules now
12:20 The regulatory war on crypto
15:41 How CLARITY could prevent another FTX
22:42 Why criminals using crypto may be easier to catch
26:20 Privacy, blockchains, and the invention of HTTPS
30:41 Government ethics and crypto
34:52 The banking lobby’s stablecoin fight
37:05 Why every major bank is building on blockchains
41:04 Developer liability as a killshot
45:23 How CLARITY provides oversight
49:30 What happens if CLARITY fails?
50:50 Regulation vs. innovation
54:12 Why America should lead
55:36 What CLARITY could unlock
Links
Marc Andreessen: https://twitter.com/pmarca
Chris Dixon: https://twitter.com/cdixon
Robert Hackett: https://twitter.com/rhackett
Why Bitcoin matters: https://a16z.com/why-bitcoin-matters/
What builders need to know about the CLARITY Act: https://a16zcrypto.com/posts/article/clarity-act-what-why-matters
Subscribe: https://www.youtube.com/@a16zcrypto
Site: https://a16zcrypto.com/
X: https://twitter.com/a16zcrypto
Newsletter: https://a16zcrypto.substack.com/
As always, none of the following should be taken as investment, business, legal, or tax advice. Please see https://a16z.com/disclosures for more important information, including a link to a list of our investments.

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59 min
July 27 How AI is Changing the Way We Build Companies (ft. Guy Wuollet and Noah Citron)
For the first time, companies can treat AI token spending almost like headcount: allocate more money, deploy more intelligence, and potentially get more work done.
That shift could change much more than engineering productivity. It could reshape how companies form, how teams are managed, how businesses are financed, and who is best positioned to build them.
In this episode, a16z crypto General Partner Guy Wuollet and Head of Engineering Noah Citron join host Robert Hackett to explore the economics of the AI-native company.
They discuss why engineering teams may soon manage token budgets like P&Ls; how AI enables companies to scale labor up and down almost instantly; and whether the future belongs to smaller, leaner businesses run by people who are unusually good at directing agents.
The conversation also covers software-engineering “pod shops,” AI as variable labor, the future of consulting and private equity, and why stablecoins and blockchains may become the default financial infrastructure for AI agents and businesses.
Finally, they ask a larger question: If AI has created so much new intelligence, why has it not yet produced an obvious jump in economic growth? And in a world where everyone can access powerful models, will intelligence matter less than grit, judgment, and agency?
Highlights
00:00 — Intro
4:01 — Why token spending is starting to resemble headcount
4:51 — Deciding how much spend is too much spend
9:04 — The agentic A/B test: How to quantify "return on tokens"
12:05 — The software-engineering "pod shop"
25:13 — Paying deference to the Machine God
26:06 — The rise (or not) of lean, AI-native microbusinesses
28:05 — Everyone's a manager? The new style of thinking for engineers
30:48 — Why AI agents may naturally use stablecoins
34:33 — When AI productivity will appear in GDP
47:49 — Why grit and agency may matter more than IQ
51:38 — How AI could create new paths for startups
54:53 — Innovation, commoditization, and creative destruction
Links:
Guy Wuollet: https://x.com/guywuolletjr
Noah Citron: https://x.com/noahcitron
Robert Hackett: https://x.com/rhackett
Subscribe: https://www.youtube.com/@a16zcrypto
Website: https://a16zcrypto.com/
X: https://twitter.com/a16zcrypto
Newsletter: https://a16zcrypto.substack.com/
As always, none of the following should be taken as investment, business, legal, or tax advice. Please see a16z.com/disclosures for more important information, including a link to a list of our investments.

Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.
59 min
July 24 The Story Behind RSA: The Invention That Secured the Internet (ft. Turing Award Winner Ron Rivest)
Before the internet could become a place to bank or transact, it needed a way for strangers to know who they were talking to, and whether a message could be trusted.
Turing Award winners Ron Rivest, Adi Shamir, and Leonard Adleman helped invent it.
In this episode of First Principles, Rivest tells the story of how they developed RSA, the first practical public-key cryptosystem. Their breakthrough made it possible to encrypt information, verify identities, and authenticate messages across an open network without requiring participants to meet or exchange a secret in advance — laying essential groundwork for the secure internet and, decades later, blockchains.
Rivest joins Tim Roughgarden, Head of Research at a16z crypto and Professor of Computer Science at Columbia University, and Dan Boneh — Professor of Computer Science at Stanford University, a16z crypto Senior Research Advisor, and the “B” in BLS signatures — for a conversation about the origins and future of modern cryptography.
They trace the field from its early days, when most cryptographic research was classified and even the meaning of “security” had not been formally defined, through the publication of the Diffie-Hellman paper and the open problem that ultimately led to RSA. Rivest recounts the night the core idea came together, why the difficulty of factoring made the system plausible, and why no one initially knew whether it would survive sustained attempts to break it.
The conversation also explores the other cryptographic primitives that underpin blockchains and the modern internet. Rivest explains why digital signatures interested him even more than encryption, how he designed the MD family of cryptographic hash functions, and why standards such as RSA, DSA, and SHA were shaped as much by politics, patents, and government pressure as by mathematics.
Finally, Rivest shares his unusually candid views on quantum computing, post-quantum security, and the deeper theoretical possibility that P could equal NP. Either development could threaten the foundations of modern cryptography — but, as Rivest argues, cryptographers have a responsibility to prepare for even the worst-case scenarios.
Highlights
00:00 – Intro: the two problems that could break modern cryptography
01:10 – Why Ron Rivest’s work underpins the internet and blockchains
08:10 – Before public-key cryptography, there was no theory of security
11:05 – The open problem that led to RSA
13:55 – The night Ron Rivest discovered the core idea behind RSA
17:55 – Why digital signatures were the real breakthrough
19:14 – The RSA challenge — and a prediction that was off by quadrillions of years
28:33 – How government pressure shaped cryptographic standards
30:36 – Designing the hash functions that made digital signatures practical
33:26 – The Fiat–Shamir transformation, explained
38:04 – Building a cryptography company before the web existed
42:31 – Will quantum computers ever become powerful enough to break RSA?
48:02 – The cryptography securing the internet, elections, and everyday life
50:11 – What surprised Dan: Quantum giveth and quantum taketh away
About First Principles
First Principles is a special limited series from a16z crypto about the scientific roots of modern computing — especially blockchains — told through rare conversations with the pioneers who helped shape the foundational ideas behind distributed systems, consensus protocols, economics, mechanism design, cryptography, zero knowledge, and more.
People often tell the story of the Bitcoin whitepaper as if it appeared out of nowhere. But the ideas behind Bitcoin — and blockchains more broadly — come from decades of computer science, economics, mathematics, and cryptography. First Principles is a guide to that lineage, as told by the people who helped build it.
Subscribe to follow along:
https://www.youtube.com/playlist?list=PLjQ9HCQMu_8yIg60YAq67HDdvp7E_T5e8
Hear more from:
Ron Rivest: https://people.csail.mit.edu/rivest/
Tim Roughgarden: https://twitter.com/Tim_Roughgarden
Dan Boneh: https://twitter.com/danboneh
Follow a16z crypto:
X: https://twitter.com/a16zcrypto
LinkedIn: https://www.linkedin.com/showcase/a16zcrypto/posts/
YouTube: https://www.youtube.com/@a16zcrypto
Substack: https://a16zcrypto.substack.com/subscribe/
As always, none of the following should be taken as investment, business, legal, or tax advice. Please see a16z.com/disclosures for more important information, including a link to a list of our investments.

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55 min
July 17 Why auction design matters (ft. Nobel economist Paul Milgrom)
Long before onchain markets made mechanism design a daily engineering problem, Nobel Prize winner Paul Milgrom was asking how prices actually form — and how better auction rules could reshape actual markets.
His work helped transform auction theory from an elegant branch of economics into a practical toolkit for allocating scarce resources, from wireless spectrum to digital ads to financial markets.
In this episode of First Principles, Tim Roughgarden, Head of Research at a16z crypto, sits down with Milgrom alongside Scott Kominers — Harvard Business School professor and a16z crypto research partner — for a conversation about auctions, information, price discovery, and the design of complex markets.
Together, they explore Milgrom’s foundational work on auction theory, the famous Milgrom-Weber paper, the Grossman-Stiglitz paradox and the Glosten-Milgrom model of market microstructure, and why understanding how prices form matters for everything from prediction markets to decentralized finance.
They also discuss Milgrom’s work designing the FCC spectrum auctions — including the auctions that helped allocate wireless spectrum for technologies like mobile broadband and 5G — and the later FCC incentive auction, a massive market design challenge that combined economics, computer science, policy, and real-world implementation.
Highlights
00:00 Intro: economics assumptions that are “just wrong”
02:19 Scott Kominers on the genius of Paul Milgrom
05:35 The price discovery problem economics forgot
07:48 The auction theory breakthrough of the 1980s
17:15 Why market microstructure matters for DeFi
24:17 When math teaches economics something new
29:22 Designing auctions people can actually use
32:40 How theory became spectrum auction design
36:22 The floppy disk that helped convince the FCC
41:05 What changed when auctions moved online
45:28 The auction that reorganized television
57:25 Why the best auctions feel simple
1:07:30 What economics and computer science can learn from each other
1:13:22 Futures markets for compute
1:15:12 Paul Milgrom’s advice for builders
About First Principles
First Principles is a special limited series from a16z crypto about the scientific roots of modern computing — especially blockchains — told through rare conversations with the pioneers who helped shape the foundational ideas behind distributed systems, consensus protocols, economics, mechanism design, cryptography, zero knowledge, and more.
People often tell the story of the Bitcoin whitepaper as if it appeared out of nowhere. But the ideas behind Bitcoin — and blockchains more broadly — come from decades of computer science, economics, mathematics, and cryptography. First Principles is a guide to that lineage, as told by the people who helped build it.
Subscribe to follow along:
https://www.youtube.com/playlist?list=PLjQ9HCQMu_8yIg60YAq67HDdvp7E_T5e8
Hear more from
Tim Roughgarden: https://twitter.com/Tim_Roughgarden
Scott Kominers: https://twitter.com/skominers
Follow a16z crypto
X: https://twitter.com/a16zcrypto
LinkedIn: https://www.linkedin.com/showcase/a16zcrypto/posts/
YouTube: https://www.youtube.com/@a16zcrypto
Substack: https://a16zcrypto.substack.com/subscribe/

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1 hr 18 min
July 14 Why markets fail — and how to fix them (ft. Nobel economist Alvin Roth)
Long before crypto made coordination programmable, Nobel Prize winner Alvin Roth was designing markets where coordination could save lives.
In this episode of First Principles, Roth tells the story of how he helped build systems for some of the hardest matching problems in the world, from where doctors train and where students go to school to how kidney donors can reach the patients who need them.
He joins Tim Roughgarden, Head of Research at a16z crypto, and Scott Kominers — Harvard Business School professor, a16z crypto research partner, and one of Roth’s former students — for a conversation about how market design moves from theory into the real world. They explore how economic theory becomes practical engineering, whether that's matching riders to Ubers, doctors to medical residencies, students to New York City high schools, or organ donors to people whose lives depend on it.
They also cover how these same problems show up in today’s crypto networks. Roth explains why markets are not just natural forces, but engineered systems; why the details of timing, congestion, incentives, and trust can make or break a marketplace; and why some of the most important markets are the ones where simply exchanging money can’t do the work.
This is a conversation about economics at its most practical and profound: how to design systems that coordinate people, solve real problems, and sometimes save lives.
00:00 Intro: Why market design matters
04:18 The economist as engineer
08:09 When theory meets the real world
07:02 Fixing the medical residency match
15:32 Why markets unravel
18:22 Redesigning NYC high school admissions
28:05 The hidden problem of congestion
34:47 How kidney exchange saves lives
45:26 How the internet changed market design
48:25 Airbnb, Uber and smarter marketplaces
51:28 Repugnant transactions and moral economics
53:32 When markets need social support
54:32 The unexpected effects of criminalizing surrogacy
01:04:58 Preference signals and the job market
01:18:53 A broken market: resettling refugees and other migrants

Hear more from:
Tim Roughgarden: https://twitter.com/Tim_Roughgarden
Scott Kominers: https://twitter.com/skominers

Follow a16z crypto:
X: https://twitter.com/a16zcrypto
LinkedIn: https://www.linkedin.com/showcase/a16zcrypto/posts/
YouTube: https://www.youtube.com/@a16zcrypto
Substack: https://a16zcrypto.substack.com/subscribe/ *

** As always, none of the following should be taken as investment, business, legal, or tax advice. Please see a16z.com/disclosures for more important information, including a link to a list of our investments.

Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.
1 hr 26 min
June 25 Leslie Lamport on the Science of Distributed Systems
Before blockchains could reach consensus, Leslie Lamport had to define what agreement even meant when computers fail, lie, or disappear.
In this episode of First Principles: The Scientific Roots of Blockchain Technology, Turing Award-winning computer scientist Leslie Lamport joins Tim Roughgarden Head of Research at a16z crypto and Professor of Computer Science at Columbia University, and a16z crypto Research Partner Ittai Abraham to trace the ideas that helped define modern distributed computing.
Lamport’s work formalized some of the field’s deepest questions: how to reason about concurrent systems, how distributed systems can agree despite failures, and how to prove that protocols do what they are supposed to do. His work on logical clocks, state machine replication, the Byzantine Generals problem, and Paxos has shaped everything from cloud infrastructure to the consensus protocols underlying modern blockchains.
The conversation begins with Lamport’s early work on concurrency and the origins of the Byzantine Generals Problem, and then turns to fault tolerance: what happens when machines crash, behave unpredictably, or even act maliciously? We also cover the feedback loop between theory and practice, the long arc of fundamental research, and how blockchains are inheriting and extending decades of distributed systems work.
Highlights
00:00 – Intro: The problem every blockchain is built to solve
02:52 – Why concurrent systems are surprisingly tricky
04:40 – The origins of the bakery algorithm
07:37 – What does it mean for a protocol to be “correct”?
12:03 – The origins of the Byzantine Generals problem — and what happens when some computers fail
17:49 – How Paxos emerged from an attempted impossibility proof
23:47 – Why theory and practice need each other
33:48 – Government funding, DARPA, and the long arc of foundational research
About First Principles
First Principles is a special limited series from a16z crypto about the scientific roots of modern computing — especially blockchains — told through rare conversations with the pioneers who helped shape the foundational ideas behind distributed systems, consensus protocols, economics, mechanism design, cryptography, zero knowledge, and more.
People often tell the story of the Bitcoin whitepaper as if it appeared out of nowhere. But the ideas behind Bitcoin — and blockchains more broadly — come from decades of computer science, economics, mathematics, and cryptography. First Principles is a guide to that lineage, as told by the people who helped build it.

Hear more from:
Tim Roughgarden: https://twitter.com/Tim_Roughgarden
Ittai Abraham: https://twitter.com/ittaia

Follow a16z crypto:
X: https://twitter.com/a16zcrypto
LinkedIn: https://www.linkedin.com/showcase/a16zcrypto/posts/
YouTube: https://www.youtube.com/@a16zcrypto
Substack: https://a16zcrypto.substack.com/subscribe/

***
As always, none of the following should be taken as investment, business, legal, or tax advice. Please see a16z.com/disclosures for more important information, including a link to a list of our investments.

Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.
37 min
June 22 Before Blockchains, There Was State Machine Replication (ft. Barbara Liskov and Tim Roughgarden)
Every blockchain today leans on replication ideas worked out in the 1980s, by a Turing Award winner who wasn’t thinking about how it might apply to money at all.
In this episode of First Principles, a16z crypto Head of Research and Columbia professor Tim Roughgarden speaks with Barbara Liskov, MIT professor, Turing Award winner, and one of the most influential computer scientists in programming languages, data abstraction, fault tolerance, and distributed computing. a16z crypto research partner Ittai Abraham joins the conversation.
The discussion traces Liskov’s path from programming languages and modularity to distributed systems research; from CLU and Argus to viewstamped replication; and from benign failures to Practical Byzantine Fault Tolerance, or PBFT — a protocol family whose ideas now shape many modern blockchain systems. Liskov explains why modularity matters, how systems researchers thought about replication in the 1980s, why view changes were such a key idea, and how PBFT extended earlier work to handle malicious behavior on the internet.
The conversation also explores the bridge between theory and practice, the importance of proofs and specifications, and why the next generation of systems research may be reshaped by AI. First Principles is a special, limited series from a16z crypto about the scientific roots of modern computing — especially blockchains — told through rare conversations with the pioneers who helped shape the foundational ideas behind distributed systems, consensus protocols, economics, mechanism design, cryptography, zero-knowledge, and more. People often tell the story of the Bitcoin whitepaper as if it appeared out of nowhere. But the ideas behind Bitcoin — and behind blockchains more broadly — come from decades of computer science, economics, mathematics, and cryptography.
First Principles is a guide to that lineage, as told by the people who helped build it.
Highlights:
00:00 Intro: How do systems stay reliable when parts fail?
01:18 Barbara Liskov’s path from programming languages to distributed systems
05:45 Why modularity is “everything”
07:22 The replication problem: keeping data available across many machines 09:58 Viewstamped replication and the “ledger” before blockchains
16:32 Why good research starts with what you don’t understand
18:10 Leslie Lamport, Paxos, and the inevitability of ideas in the right time, in the right place
21:48 Practical Byzantine Fault Tolerance: what changes when replicas can lie
19:35 How PBFT bridged theory and practical systems
22:38 Why you should never trust an individual replica
28:39 Why blockchains are state machine replication in the wild
31:27 AI, verification, and the future of computer science

Follow:
Tim Roughgarden: https://twitter.com/Tim_Roughgarden
Ittai Abraham: https://twitter.com/ittaia

Follow a16z crypto: X: https://twitter.com/a16zcrypto
LinkedIn: https://www.linkedin.com/showcase/a16zcrypto/posts/
YouTube: https://www.youtube.com/@a16zcrypto
Substack: https://a16zcrypto.substack.com/subscribe/

*** As always, none of the following should be taken as investment, business, legal, or tax advice. Please see a16z.com/disclosures for more important information, including a link to a list of our investments.

Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.
36 min
June 22 How Bitcoin Rewired a Classic Computer Science Problem (ft. Tim Roughgarden and Ittai Abraham)
Bitcoin often gets credited with inventing trustless consensus. It didn’t.
The problem was named decades earlier — in the world of distributed computing — and researchers spent years studying how machines could reach agreement even when some participants were faulty, adversarial, or corrupt. What Bitcoin did was something different: It solved a classic Byzantine agreement problem in a radically new, permissionless setting. And it took the research world years to fully recognize what Satoshi had done.
In this episode of First Principles, a16z crypto Head of Research and Columbia professor Tim Roughgarden is joined by a16z crypto research partner Ittai Abraham — one of the world’s leading researchers in Byzantine agreement and consensus protocols, a founding member of VMware’s blockchain project, and founder of the technical blog Decentralized Thoughts — to unpack the scientific roots of blockchain consensus.
Together, Tim and Ittai trace the line from classic distributed systems research to Bitcoin, proof-of-stake, Tendermint, Casper, DAG-based protocols, Solana’s Alpenglow, and the modern race for higher throughput and lower latency. Along the way, they explain why concepts like Byzantine fault tolerance, state machine replication, safety, liveness, and partial synchrony are not just academic abstractions — they are the language and design principles behind today’s blockchain protocols.
This conversation kicks off First Principles: The Scientific Roots of Blockchain Technology — a special, limited series from a16z crypto on the scientific ideas behind modern computing — especially blockchains — told through conversations with the pioneers who helped create them, including Barbara Liskov, Leslie Lamport, and more. Hosted by Tim Roughgarden, the series explores the foundational concepts behind distributed systems and consensus protocols; economics, mechanism and market design; and cryptography, from digital signatures to zero knowledge. People often tell the story of the Bitcoin whitepaper as if it appeared out of nowhere.
But the ideas behind Bitcoin — and behind blockchains more broadly — come from decades of computer science, economics, mathematics, and cryptography. First Principles is a guide to that lineage, told by the people who helped build it.
Highlights
00:00 Introduction to First Principles: The Scientific Roots of Blockchain Technology
00:56 Why consensus matters for blockchains
02:30 Byzantine agreement: The old computer science problem Bitcoin made practical
04:34 Blockchains as a shared system of record: State machine replication and blockchain state
06:41 How two research worlds — distributed computing and crypto — began to converge
07:49 Proof of work vs. proof of stake
09:27 Why Ethereum’s move to proof-of-stake took years
11:08 When crypto rediscovered decades of distributed systems research
11:50 Why BFT became practical 12:49 Throughput, latency, and modern consensus design
14:05 DAG-based protocols and faster blockchains
15:25 Peace time vs. war time: why modern blockchains need two modes
16:47 Theory, practice, and the future of blockchain research

Follow:
Tim Roughgarden: https://twitter.com/Tim_Roughgarden
Ittai Abraham: https://twitter.com/ittaia

Follow a16z crypto:
X: https://twitter.com/a16zcrypto
LinkedIn: https://www.linkedin.com/showcase/a16zcrypto/posts/
YouTube: https://www.youtube.com/@a16zcrypto
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20 min

About a16z crypto show

From the publisher's feed

The a16z crypto show explores how decentralized networks are reshaping money, ownership, and the architecture of the internet. We go beyond the hype to look at what’s actually working, what isn’t, and what comes next as crypto continues to go mainstream and blockchains become core infrastructure.