StarZero All shows Try the podcast clipper →

Justin Johnson

Co-founder, World Labs · 1 appearance on the record.

computed by AI from the episodes · how this works → · full disclaimer →

founderscientistacademic@jcjohnss ↗LinkedIn ↗web.eecs.umich.edu/~justincj ↗

Justin Johnson is a co-founder of World Labs, a spatial intelligence startup building generative 3D world models. He was previously a computer science professor at the University of Michigan and a research scientist at FAIR.

7statements → 4claims → 3claims resolved → 67%fully supported → 3.71/5average certainty → 2.14/5average debate potential → 6said about them ↓

2 supported 0 partly supported 1 contradicted 1 not checkable as stated how the 4 claims stand · each chip opens the sources

4 assertions · 3 insights · every statement was checked. The predictions and assertions are the 4 claims: statements the public record can support or contradict. 3 are resolved, and 1 names no date, number or outcome precise enough to check. Everything else (opinions, insights, what ifs, disclosures) can never be settled by the record, so it carries no assessment.

The record, in short

What the tape says about how Justin argues and how the claims held up. Everything they said, and everything said about them, is in the tabs below.

Their most notable supported claim

Assertion Supported
Johnson: Gaussian splats render in real time on nearly any client device
“Gaussian splats are really cool because you can render them in real time really efficiently. So you can render on your iPhone, render, render everything. And that's how we get that sort of precise camera control because The splats can be rendered real time on …”
Justin Johnson Nov 25, 2025 ▶ 34:46 After LLMs: Spatial Intelligence and World Models — Fei-Fei Li & Justin Johnson, World Labs

Their most notable contradicted claim

Assertion Contradicted
Johnson: Nvidia Blackwell offers roughly same performance per watt as Hopper
“Like, if you look at the numbers, like, even going from Hopper to Blackwell, like, the performance per watt is about the same. They mostly make the number of transistors go up, and they make the chip size go up, and they make the power usage go up. But even fr…”
Justin Johnson Nov 25, 2025 ▶ 13:01 After LLMs: Spatial Intelligence and World Models — Fei-Fei Li & Justin Johnson, World Labs

Everything Justin Johnson said on Latent Space that made the record, most notable first. Filter by type, assessment or year in the ledger →

Assertion Contradicted
Johnson: Nvidia Blackwell offers roughly same performance per watt as Hopper
“Like, if you look at the numbers, like, even going from Hopper to Blackwell, like, the performance per watt is about the same. They mostly make the number of transistors go up, and they make the chip size go up, and they make the power usage go up. But even fr…”
Justin Johnson Nov 25, 2025 ▶ 13:01 After LLMs: Spatial Intelligence and World Models — Fei-Fei Li & Justin Johnson, World Labs
Insight
Johnson: Pixels offer a more lossless world representation than tokenized text
“And then like you actually lose something if you translate to this like purely tokenized representations that we use in LLMs, right? Like you lose the font, you lose the line breaks, you lose sort of the two D arrangement on the page. And for a lot of cases, f…”
Justin Johnson Nov 25, 2025 ▶ 22:11 After LLMs: Spatial Intelligence and World Models — Fei-Fei Li & Justin Johnson, World Labs
Assertion Not checkable as stated
Johnson: Academic labs can no longer train state-of-the-art AI on few GPUs
“Like five or 10 years ago, you really could train state-of-the-art models in the lab even with just a couple of GPUs. But, you know, because that technology was so successful and scaled up so much, then you can't train state-of-the-art models with a couple of …”
Justin Johnson Nov 25, 2025 ▶ 9:51 After LLMs: Spatial Intelligence and World Models — Fei-Fei Li & Justin Johnson, World Labs
Assertion Supported
Johnson: Gaussian splats render in real time on nearly any client device
“Gaussian splats are really cool because you can render them in real time really efficiently. So you can render on your iPhone, render, render everything. And that's how we get that sort of precise camera control because The splats can be rendered real time on …”
Justin Johnson Nov 25, 2025 ▶ 34:46 After LLMs: Spatial Intelligence and World Models — Fei-Fei Li & Justin Johnson, World Labs
Insight
Johnson: Physical theory-building stems from interactive falsification, not model modality
“Because we're constantly interacting with the world, we're constantly having to build theories about what's happening in the world around us, and then falsify or add evidence to those theories. And I think that that kind of process writ large and scaled up is …”
Justin Johnson Nov 25, 2025 ▶ 54:35 After LLMs: Spatial Intelligence and World Models — Fei-Fei Li & Justin Johnson, World Labs
Insight
Johnson: Transformers are natively models of sets, not sequences
“Transformers are actually not a model of sequences. A transformer is natively a model of sets.”
Justin Johnson Nov 25, 2025 ▶ 56:45 After LLMs: Spatial Intelligence and World Models — Fei-Fei Li & Justin Johnson, World Labs
Assertion Supported
Johnson: AI compute per model has scaled one million-fold since 2012
“And if you think about, you know, AlexNet required this jump from CPUs to GPUs, but even from AlexNet to today, we're getting about a thousand times more performance per card than we had in AlexNet days. And now it's common to train models, not just on one GPU…”
Justin Johnson Nov 25, 2025 ▶ 4:13 After LLMs: Spatial Intelligence and World Models — Fei-Fei Li & Justin Johnson, World Labs

The other half of the tape: Justin Johnson's own voice is left out of every number here. Other people bring the name up 5 times in 3 episodes on Latent Space. 1 statement on the record names them. every mention, with the transcript →

Who brings them up most Shawn Wang 1Michael Royzen 1

Statements about Justin Johnson, by other people (1)

Disclosure
Li: World Labs was founded to build spatial intelligence beyond LLMs
“I think around, you know, more than two years ago, for sure, I think both independently, both of us have been looking at the development of the large models and thinking about What's beyond language models and this idea of building world models, spatial intell…”
Fei-Fei Li Nov 25, 2025 ▶ 2:14 After LLMs: Spatial Intelligence and World Models — Fei-Fei Li & Justin Johnson, World Labs

Every mention by year

tap a year for its mentions
0021312023202420252026episodesmentions
0112023202420252026episodes it came up in
001.50.5312023202420252026episodesmentions per episode
2026 1 mention in 1 episode
2025 3 mentions in 1 episode
2023 1 mention in 1 episode

Appearances (1)

EpisodeDateSpeaking time
After LLMs: Spatial Intelligence and World Models — Fei-Fei Li & Justin Johnson, World Lab Nov 25, 2025 22m
Made with StarZero

Turn any episode into a week of clips.

This entire site, over 200 episodes transcribed, diarized, checked and made playable, runs on the StarZero media pipeline. Drop in your own episode and the podcast clipper finds the moments worth sharing, cuts them, captions them, and reframes them for every feed.

Try the podcast clipper Learn more