Pinned Tweet
You know an event has landed when 200+ researchers, verification engineers, founders and investors stay in their seats from 4 PM to 11 PM on a Wednesday,
for a conversation about formal verification.
This is one of those things that happen only at SF !
(1/3)
The FV Summit retweeted
Its really hard to predict what AI will eventually become good at. Intuition says that domain where solutions are "driven" by human creativity will by the last to be solved by language models, but this is not well defined.
I think language models will/have perform(ed) really well in domain were verification is available.
If you can find a quick way of saying something is correct or incorrect you can have language models hill climb
code generation -> compiler
proof generation -> Lean4
......
The FV Summit retweeted
We should spend time talking about problems we haven’t solved yet.
I will be sharing a set of research problems that I believe are important for the formal community to make progress on today, and that we’re actively thinking about at Pramaana Labs
Some are problems we’ve made progress on, while others are still very much open questions for us. I’d love to share how we’re thinking about them, hear how others approach these challenges, and learn from the broader community.
This is an exciting space to be working in, and I’m sure there’s a lot we can learn from each other. If you’re in San Francisco and curious about the formal landscape, I’d love for you to join us! luma.com/6r0fofzz
And a huge thanks to Adi Baradwaj and Radoslav Kirov for inviting me
The FV Summit retweeted
Interpretability has been vastly under-explored relative to its importance.
As models become more deeply embedded in real workflows, we’ll need better means to ensure understandability, auditability and verifiability of the reasoning/inference.
The combination of mechanical interpretability along with formal methods is the way to go about this.
Research has been super exciting lately!
1) A potentially breakthrough approach to interpreting LLM weights: already-clean.goodfire.com/
2) Major advances in the formalization of mathematics, raising equally important questions about interpretability.
I think interpretability is going to be a really important research frontier. There are many ways to approach it, from understanding model weights to developing better ways to audit and verify model outputs.
Ultimately, these systems are built to interact with humans, and we need better ways to understand what they are doing, how they work, and whether we can trust their outputs.
Its an exciting time to be doing research, with so much happening across the community. And it feels like the perfect time to get together and discuss where things are heading.
🇭🇺 Ill be in Budapest 24th-29th October for EMNLP, where our paper on evaluating formally verified co-reasoning systems for education was accepted: drive.google.com/drive/folde….
I'd love to meet anyone interested in these topics. There's so much happening right now, and I'd love to exchange ideas with people from different backgrounds! I’m also always happy to chat about what we’re exploring at @PramaanaLabs ! If you'll be in Budapest, lets connect!
The most trustworthy AI systems will be the ones are independently auditable and generate run-time verification.
Formal methods are how we get there.
A really insightful post by @satyanadella. Language models are scaling intelligence at an unprecedented rate, which begs the question: how do we build trust around them?
There are two ways to establish trust:
1. Trust in an authority: relying on a system or institution because we believe it will make the correct decision.
2. Trust through auditability: being able to inspect a decision, understand its basis, and independently verify its correctness.
Today, individuals using LLMs are responsible for its outputs: the operator of the model is the authority in which we place our trust. Auditability too comes from the operator, often an explanation of the solution the model provided.
However, with intelligence scaling at an unprecedented rate; agentic swarms in the thousands; trillions of lines of AI generated code: the operators that hold trust and accountability can’t scale at the same rate.
We are in need of an independent mechanism for establishing trust in these systems.
This mechanism should sit outside the model itself. It should provide both a stamp of authority for accepting a decision and an auditable explanation of why that decision is correct.
Formal verification can provide the first: a machine-checkable guarantee that a result satisfies a precisely specified set of rules. Interpretable proofs can provide the second: a trace that anyone can inspect to understand the formal reasoning and verify the result.
@satyanadella puts it well “The most trustworthy system won’t be the one with the model we trust most. It will be the one that lets us trust the model the least.”
This is what we are building at Pramaana.
Come join us.
The FV Summit retweeted
Math is quietly becoming the backbone of the next generation of AI startups, and this is a great roundtable that throws light on how formal methods are moving from pure research into practical AI startups that need to prove their outputs.
Thank you @KanuGulati for highlighting us on the @twistartups podcast.
Jump to 05:45 where she talks about how we formalize taxes and code so AI can prove its work.
xitter.cf/twistartups/status/210…
More VCs now sit on the boards of startups going head-to-head, and the Factory vs. Cognition fight just showed how messy that can get. On a TWIST VC round table, guest host Deedy Das of Menlo Ventures, a Factory investor, is joined by Kanu Gulati of Khosla Ventures, which backs both companies, Chris Farmer of SignalFire, and Sheel Mohnot of Better Tomorrow Ventures.
Kanu explains how her firm walls off partners on rival deals, Chris argues overlap is inevitable as startups pivot, and Sheel asks whether founders will start turning that money down.
Plus we're also talking about whether personal AI agents like Instinct are really worth $10 billion, what the panel actually uses them for, and whether SaaS is still worth funding. All that and more on this week's VC roundtable.
@jason @lons @deedydas @MenloVentures @KanuGulati @khoslaventures @chriswfarmer @SignalFire @pitdesi @btv_vc
0:00 VC roundtable with guest host Deedy Das
1:58 Plaud: If your work depends on conversations - interviews, meetings, calls - you need a Plaud NotePin S. You can check it out at Plaud.ai/twist and use code TWIST for 10% off!
2:46 OpenAI's math results and what's left to invest in
5:45 Formalizing taxes and code so AI can prove its work
7:12 Why science breakthroughs still need the real world
10:19 Odoo: The all-in-one business platform. Your first app is free! Get started today at Odoo.com/twist
11:29 Can startups compete with the labs on compute?
13:37 Private data and vertical AI as the moat
19:29 Would you invest in AI training data companies?
21:09 Northwest Registered Agent: Got a new business idea? Northwest Registered Agent helps you bring it to life. Get a free domain, email, phone number, and more - with no purchase required! - Learn more at northwestregisteredagent.com…
27:04 What a great founder looks like in the AI era
29:48 Quo: Quo (formerly OpenPhone) gives you a clean, modern way to handle every customer call, text, and thread all in one place. Try it free at quo.com/TWiST
35:10 Is Instinct worth $10 billion?
42:06 Can Muse reach a billion daily users?
45:24 Favorite personal agent use cases
49:41 What happens when everyone's agent makes the same call
53:52 Factory vs. Cognition and VCs backing rivals
1:04:24 Is SaaS still worth venture money?
1:10:24 Where the panel gets its information
1:15:20 What a seed fund means in 2026
🎥 Watch the full episode here 👇
The FV Summit retweeted
OpenAI just released hundreds of new mathematical results, many of them backed by Lean proofs. I have mixed feelings about how this material was presented and what it means for the mathematical community.
But one thing is clear: this is not just about the intelligence of frontier models. It is also a statement about how verification enables frontier discoveries. Formal verification has never been more relevant.
We would not have frontier mathematical capability today without the large-scale community effort behind Lean 4 and Mathlib.
Domain experts, in this case mathematicians, still have to verify the translation of their field's foundational rules. As we are seeing with mathematics, when the rules are stated precisely, verification can scale intelligence.
Formalizing a field used to require two kinds of expert in one person: a formal expert and a domain expert. Today domain experts can do it on their own with the help of LLMs. The catch is that they need to be able to read, ratify and query the formal representation correctly.
We need to build interfaces and systems that let our lawyers, doctors, accountants and legislators encode their knowledge precisely. That is what will let intelligent models push the frontier across all surfaces of human knowledge.
If this interests you, reach out. I would love to chat.
The FV Summit retweeted
Look at the joy of a mind whose work is finally proven. Hardy's insistence on rigor gave Ramanujan that.
We're bringing the same feeling to AI outputs, knowing without uncertainty that something is true, to real-world domains.
Proof turns brilliance into something known and established forever. And shipping these proofs for every output is part of our design.
The FV Summit retweeted
The FTC just made the case for Responsible AI concrete. If harmful agent actions fall on the developer, we need defined guardrails to keep agentic AI under check.
The answer to this is formalized rule books and runtime verification of every task before it executes.
The FV Summit retweeted
Formal is the new frontier! We are already seeing the move from buggy software systems to ones we can prove are correct every time.
@PramaanaLabs will bring this to mission critical real world systems.
Drug discovery, tax, city plans, medical diagnosis, policy making will all have proofs of correctness.
I used Opus 5.5 to formally verify the Claude Agent SDK using Lean. A couple short prompts = 16 PRs fixing various bugs and race conditions. Video attached.
TLA+ also works well. I sometimes combine Lean and TLA+ to look for issues around data flow, concurrency, and state mgmt.
I don't know either language well, but Claude is excellent at both. This approach is super useful for formally modeling your code and finding bugs that a human probably wouldn't have spotted.
Is formal verification the future of coding (or at least, bug finding)?
The FV Summit retweeted
I used Opus 5.5 to formally verify the Claude Agent SDK using Lean. A couple short prompts = 16 PRs fixing various bugs and race conditions. Video attached.
TLA+ also works well. I sometimes combine Lean and TLA+ to look for issues around data flow, concurrency, and state mgmt.
I don't know either language well, but Claude is excellent at both. This approach is super useful for formally modeling your code and finding bugs that a human probably wouldn't have spotted.
Is formal verification the future of coding (or at least, bug finding)?
The FV Summit retweeted
There’s a lot of excitement about AI + formal verification right now.
I’ve worked on this since 2018. I share the excitement—but the progress has also made me rethink what formalization can solve.
What Happens When Formalization Becomes Cheap?
yangky11.github.io/blog/ai-a…
The FV Summit retweeted
Happy to share that the FACTS Leaderboard has been accepted as a spotlight at NeurIPS Evaluations & Datasets track!
One area of post-training research I worked on at Google DeepMind was model self-improvement: using Gemini to synthesize questions that remain hard for frontier models with search.
A key idea was to shape the retrieval neighborhood so Gemini could explore interesting, non-obvious connections across documents and synthesize grounded questions around those connections.
arxiv.org/abs/2512.10791
The FV Summit retweeted
"As AI and AI-assisted mathematicians produce more (purported) proofs than ever before, AI-assisted formalization takes part of the load off human reviewers. We expect it will become common to produce a formalized proof alongside any write-up intended for a human reader."
Checking that a major mathematical proof is correct can take years. Formalization—converting the mathematical reasoning into a form computer proof assistants like Lean can verify—can help.
Last month, Claude completed the first formalized proof of Fermat’s Last Theorem, one of the most famous theorems of all time. This was a project experts thought would take many years. It is the largest Lean proof ever written.
Fermat’s Last Theorem was first proven in 1995 by Sir Andrew Wiles, more than 350 years after it was conjectured. Our proof, which totals over 13 million lines of code, provides machine verification. More importantly, it proves over 29,000 other theorems that the proof requires, across many areas of math which had never before been formalized.
We see this as a major step in the long process of firming up the core of mathematical knowledge, building on work from three centuries of mathematicians and hundreds of contributors to Lean and Mathlib. We are optimistic that AI-assisted verification of mathematical proofs will help reduce the burden of refereeing mathematics in an era where more proofs are being produced than ever before.
You can read about the process on our Science Blog: anthropic.com/research/forma…
And see the complete proof on GitHub: github.com/anthropics/fermat…
The FV Summit retweeted
AI will be steered by formalisation. In every domain.
An update on Lean (auto)-formalization.
Speaking about my own research workflow, in 2026, we have gone from:
March: Lean formalization is not possible (for my papers).
May: Lean formalization is possible... but way too costly in time and tokens to be practical most of the time.
July: Lean formalization is now practical. I can probably formalize most of my papers now before they hit arxiv.
August: Lean formalization is now essential-- it increases efficiency of my workflow dramatically.
That is, the papers are getting written *informally* and finished much faster because of the Lean formalization.
The FV Summit retweeted
"We have to accept the possibility that all mathematics could fall to AI within some months, however unsettling that might seem."
The part of mathematics that is like playing Chess or Go, coming up with ever cleverer moves, will be conquered by AI. That is now evident.
The part of mathematics that is like inventing an entire new game like Chess _that humans would consider interesting_ is much harder but then humans do that very very rarely too. The "humans would consider interesting" could be considered a fundamental limit of AI or merely a face-saving formula to protect human ego but humans set the rules (for now!).
Where does programming fit here? It increasingly seems to me that a very large fraction of software code could be produced competently and _correctly_ by AI. The "correctly" part is being addressed with proof systems like Lean that are applied to mathematical theorem proving today but soon will be applied to verify the software code produced by AI.
The point is not that "AI will do it all". There will be humans involved in the process. The key question is "how many humans are needed" and the answer right now is sobering and unsettling.
All of us in software need to figure out how to stay relevant. Let me get back to work. Please wish us luck 🙏
We have to accept the possibility that all mathematics could fall to AI within some months, however unsettling that might seem.
ie AI better than all humans at math.
That's because math is not fundamentally "hard"... primates are just really bad at it. We did not evolve to be efficient at manipulating math symbols.
We think of Terrence Tao as a legend, and he is on a human scale -- multiple standard deviations better at math than me. But to an AI, going from Will-level ability to Terrence-level math ability just means something like a 10x bigger context window, 10x bigger RL run, and 10x more test-time compute.
Solving math in the past seemed to require some creative human spark we couldn't understand, but it's increasingly looking more like a mechanical search process over symbols. The aura and mystique mathematicians maintained for millennia can be reframed as them being extremely talented at this mechanical process. They can't compete with an alien creature trained exactly for this purpose, with compute specs far beyond Terrence.
By 2027 we'll be cranking out mathematical beauties each morning like Alan Turing cranking out Enigma codes before breakfast. We'll still be bottlenecked by compute for a few years, so the big discoveries will come gradually -- those will take the most computation.
Is this sad? Well like software engineering, those people who enjoy it for love of the craft or for their unique abilities compared to other humans will feel diminished. But those who love it for the end results will relish in a golden age of math.
Humans will still be the ones mapping the mathematical landscape. The AIs will act like the helicopters taking us wherever we want to go. You gotta pay to ride in compute.
You could map different human intellectual activities to whether it's "hard" in a computational sense. Human-level chess is easy, that's why computer solved it early. Moving limbs in physical space however is very hard. We're good at it bc we benefited from hundreds of millions of years of evolution.
Software engineering is somewhere in the middle, because it's intertwined with a messy complex physical world filled with computationally hard emotions and group dynamics.
So that's why weirdly we'll soon have AIs that dominate all humans on math, and yet we won't fully trust them as software engineers.
The FV Summit retweeted
In the last 2 days:
1) Fermats' last theorem has been formalized in Lean4 anthropic.com/research/forma…
2) A new prime gap of 186 has been discovered and formalized in Lean4 github.com/openai/PrimeGaps1…
We are now in an age where proof generation is abundant.
The blocker now is bringing this notion of proof beyond mathematics.
The challenge is taking knowledge from the heads of experts in domains like medicine, tax, law, physics, and government policy and making it precise enough for a machine to reason with. Today, many of these rules simply sit in the heads of people.
We call this problem domain formalization, and this will be the next frontier of formal automated reasoning
This will fundamentally change how we use computers to reason about the world.
The FV Summit retweeted
Isn’t it weird that we’ve built ultimate hacking machines, but none that can reliably defend against those hacks?
It turns out that there is a good reason for this; hacking requires generating one example that breaks the system, while security requires showing that there can be no example that ever breaks the system.
Language models are bad at any reasoning that involves exhaustively eliminating all possibilities under certain constraints.
The issue is that it’s hard to make an LLM understand the complete set of constraints. If you put them all in context, it may forget some of them or fail to reason about them consistently.
This “other half of reasoning” needs to be addressed.
For exhaustive search to be reliable, the rules governing the search need to be precisely defined.
Formalization for real-world domains is one way towards this goal.
We wrote more about this in our blog: pramaanalabs.ai/blog/the-oth… @PramaanaLabs
The FV Summit retweeted
I have decided to leave math academia.
Not because of burnout, the academic job market, or a loss of love for mathematics. Surprisingly, it is because of how much mathematics I could do with LLMs over the last few months.
For most of my life, pursuing mathematics felt like the obvious choice. It gave me a sense of purpose, rooted in the search for hidden truths in God’s Book.
Over the past few months, that conviction has been shaken. With LLMs, I could get several breakthroughs on problems I care deeply about and had worked on for years during my PhD. This progress might have taken years of my academic life if not for LLMs.
This could have strengthened my conviction that mathematics was my calling. Instead, it undermined it. With each passing week, my role in the discovery loop seemed to grow smaller.
What made mathematics meaningful to me was never just the final answer. It was the struggle: months or years of exploration, failed approaches, and deep thought before a hidden structure finally became visible. That struggle gave me a sense that the result was truly mine. Prompting my way to answers, without the struggle that once defined the process, no longer felt like the same vocation. The answer might be just as beautiful, but it did not feel earned in the same way.
I now believe that we are rapidly approaching a world in which most answers from God’s Book will be only a prompt away. Once I truly internalized that possibility, dedicating much of my life to finding those answers slightly earlier no longer felt as meaningful as it once had.
But one problem kept bothering me: How do we know the oracle is right?
Intelligence (and hence the amount of math papers) is becoming abundant and cheaper by the day. Trust is not.
The proofs produced by these systems can be highly sophisticated, and their errors can be extremely subtle. Determining whether an apparent breakthrough was actually correct sometimes took me days. Until it is verified, a beautiful proof is not different from slop.
That gap drew me toward formal verification and eventually toward formalizing math proofs in Lean, including proofs of several longstanding conjectures and Erdős problems discovered with the help of LLMs. I began to see verification as a central intellectual bottleneck. Intelligence is useful only when its outputs can be trusted.
So I am leaving math academia. I am shifting my attention from discovering answers to building systems that can certify them.
I am very excited to be joining @PramaanaLabs to work on this challenge. Over the next few years, I hope to help build a future in which increasingly powerful systems are not merely intelligent, but provably correct and reliable across problems far beyond mathematics.
The FV Summit retweeted
We formalized all of FIFA rules as a fun weekend experiment to see what verified AI would unlock in the field of sports!
It can tackle nuanced questions unlike any other model out there!
Do give @RefereeASI a shot!
Replying to @ranjan_vittal
No — the goal does not stand.
Here's why:
1) The ball went out of play, so play was stopped and the restart is a dropped ball.
2) The rules say a goal cannot be scored straight from a dropped ball — the ball has to be touched by at least two different players before a goal can count.
3) In this case only one player touched it (he dropped it and kicked it in himself), so that condition isn't met.
4) Because the ball went straight into the opponents' goal off just that one player, no goal is awarded.
5) The correct restart is a goal kick to the opposing team.
For comparison, you CAN score directly from a kick-off, free kick, penalty, goal kick, or corner — but never from a dropped ball.
Full details: formalizer-staging.web.app/p…
The FV Summit retweeted
Replying to @ranjan_vittal
No — the goal does not stand.
Here's why:
1) The ball went out of play, so play was stopped and the restart is a dropped ball.
2) The rules say a goal cannot be scored straight from a dropped ball — the ball has to be touched by at least two different players before a goal can count.
3) In this case only one player touched it (he dropped it and kicked it in himself), so that condition isn't met.
4) Because the ball went straight into the opponents' goal off just that one player, no goal is awarded.
5) The correct restart is a goal kick to the opposing team.
For comparison, you CAN score directly from a kick-off, free kick, penalty, goal kick, or corner — but never from a dropped ball.
Full details: formalizer-staging.web.app/p…



























