[whymauri]

I used to work at a drug discovery startup. A simple model generating directly from latent space 'discovered' some novel interactions that none of our medicinal chemists noticed e.g. it started biasing for a distribution of molecules that was totally unexpected for us.

Our chemists were split: some argued it was an artifact, others dug deep and provided some reasoning as to why the generations were sound. Keep in mind, that was a non-reasoning, very early stage model with simple feedback mechanisms for structure and molecular properties.

In the wet lab, the model turned out to be right. That was five years ago. My point is, the same moment that arrived for our chemists will be arriving soon for theoreticians.

[wenc]

A lot of interesting possibilities lie in latent space. For those unfamiliar, this means the underlying set of variables that drive everything else.

For instance, you can put a thousand temperature sensors in a room, which give you 1000 temperature readouts. But all these temperature sensors are correlated, and if you project them down to latent space (using PCA or PLS if linear, projection to manifolds if nonlinear) you’ll create maybe 4 new latent variables (which are usually linear combinations of all other variables) that describe all the sensor readings (it’s a kind of compression). All you have to do then is control those 4 variables, not 1000.

In the chemical space, there are thousands of possible combinations of process conditions and mixtures that produce certain characteristics, but when you project them down to latent variables, there are usually less than 10 variables that give you the properties you want. So if you want to create a new chemical, all you have to do is target those few variables. You want a new product with particular characteristics? Figure out how to get < 10 variables (not 1000s) to their targets, and you have a new product.

[whymauri]

At the end of the generative funnel we had a filter and it used (roughly) the mechanism you're describing.

https://www.pnas.org/doi/10.1073/pnas.1611138113

You summarized it very well!

[timClicks]

It's been a while since I've played in the area, but is PCA still the go to method for dimensionality reduction?

[siavosh]

In terms of terminology, is it accurate to interpret the latent variables as the “world model” of the neural network?

[svantana]

Interesting! Depending on your definition, "automated invention" has been a thing since at least the 1990's. An early success was the evolved antenna [1].

1. https://en.wikipedia.org/wiki/Evolved_antenna

[hhh]

IBM has done this with pharmaceuticals for ages no? That’s why they have patents on what would be the next generation of ADHD medications e.g. 4F-MPH?

[kmarc]

Reminds me of this story on the Babbage podcast a month ago:

https://www.economist.com/science-and-technology/2025/07/02/...

My understanding is, iterating on possible sequences (of codons, base pairs, etc) is exactly what LLMs, these feedback-looped predictor machines, are especially great at. With the newest models, those that "reason about" (check) their own output, are even better at it.

[apimade]

Warning the below comment comes from someone who has no formal science degree, and just enjoys reading articles on the topic.

Similar for physicists, I think there’s a very confusing/unconventional antenna called the “evolved antenna” which was used on a NASA spacecraft. The idea behind it was supported from genetic programming. The science or understanding “why” the way the antenna bends at different areas supporting increased gain is not well understood by us today.

This all boils down to empirical reasoning, which underlies the vast majority of science (or science adjacent fields like software engineering, social sciences etc).

The question I guess is; does LLMs, “AI”, ML give us better hypothesis or tests to run to support empirical evidence-based science breakthroughs? The answer is yes.

Will these be substantial, meaningful or create significant improvements on today’s approaches?

I can’t wait to find out!

[pojzon]

If AI comes up with new drugs or treatments - does it mean its a public knowledge and cant be copyrighted ?

Wouldnt that mean a fall of US pharmaceutical conglomate based on current laws about copyright and AI content?

[jillesvangurp]

You are confusing copyright and patents, which are two very different things. And yes, companies or people wielding AIs can patent anything that hasn't been claimed by others before.

[selkin]

Drugs discovered by humans are not under the protections of copyright as well.

[ACCount37]

Hallucinations or inhuman intuition? An obvious mistake made by a flawed machine that doesn't know the limits of its knowledge? Or a subtle pattern, a hundred scattered dots that were never connected by a human mind?

You never quite know.

Right now, it's mostly the former. I fully expect the latter to become more and more common as the performance of AI systems improves.

[brandonb]

This is really cool. Have you (or your colleagues) written anything about what you learned about ML for drug discovery?

[lukev]

Ok but I have to point out something important here. Presumably, the model you're talking about was trained on chemical/drug inputs. So it models a space of chemical interactions, which means insights could be plausible.

GPT-5 (and other LLMs) are by definition language models and though they will happily spew tokens about whatever you ask, they don't necessarily have the training data to properly encode the latent space of (e.g) drug interactions.

Confusing these two concepts could be deadly.

[Difwif]

Seems short sighted to me. LLMs could have any data in their training set encoded as tokens. Either new specialized tokens are explicitly included (e.g: Vision models) or the language encoded version of everything that usually exists (e.g: the research paper and the csv with the data).

To improve next token prediction performance on these datasets and generalize requires a much richer latent space. I think it could theoretically lead to better results from cross-domain connections (ex: being fluent in a specific area of advanced mathematics, quantum mechanics, and materials engineering is key to a particular breakthrough)