Marco Cuturi

📢 We’re looking for a researcher in in cogsci, neuroscience, linguistics, or related disciplines to work with us at Apple Machine Learning Research! We're hiring for a one-year interdisciplinary AIML Resident to work on understanding reasoning and decision making in LLMs. 🧵

On Fitting Flow Models with Large Sinkhorn Couplings Flow models transform data gradually from one modality (e.g. noise) onto another (e.g. images). Such models are parameterized by a time-dependent velocity field, trained to fit segments connecting pai...

We also introduce two coupling approaches advocated this summer to improve FM training: using either very large sharp Sinkhorn couplings (arxiv.org/abs/2506.05526) or, even better, semidiscrete couplings (arxiv.org/abs/2509.25519), as proposed with Alireza Mousavi-Hosseini and
@syz.bsky.social

We have been working with Michal Klein on pushing a module to train *flow matching* models using JAX. This is shipped as part of our new release of the OTT-JAX toolbox (github.com/ott-jax/ott)

The tutorial to do so is here: ott-jax.readthedocs.io/tutorials/ne...

Afternoon talks by:
@marcocuturi.bsky.social
Elena Agliari
Jan Gerken

Thanks all for the great talks, conversations, and engagement! Fingers crossed we get to host this event a 4th time next year and see many of you back in Gothenburg 🤞🇸🇪

🚀 Excited to share LinEAS, our new activation steering method accepted at NeurIPS 2025! It approximates optimal transport maps e2e to precisely guide 🧭 activations achieving finer control 🎚️ with ✨ less than 32 ✨ prompts!

💻https://github.com/apple/ml-lineas
📄https://arxiv.org/abs/2503.10679

It's that time of the year! 🎁

The Apple Machine Learning Research (MLR) team in Paris is hiring a few interns, to do cool research for ±6 months 🚀🚀 & work towards publications/OSS.

Check requirements and apply: ➡️ jobs.apple.com/en-us/detail...

More❓→ ✉️ mlr_paris_internships@group.apple.com

While working on semidiscrete flow matching this summer (➡️ arxiv.org/abs/2509.25519), I kept looking for a video illustrating that the velocity field solving the Benamou-Brenier OT problem is NOT constant w.r.t. time ⏳... so I did it myself, take a look! ott-jax.readthedocs.io/tutorials/th...

LLMs are currently this one big parameter block that stores all sort of facts. In our new preprint, we add context-specific memory parameters to the model, and pretrain the model along with a big bank of memories.

📑 arxiv.org/abs/2510.02375

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Wow! Finally OT done on the entire training set to train a diffusion model!

Then there's always 𝜀 regularization. When 𝜀=∞, we recover vanilla FM. At this point we're not completely sure whether 𝜀=0 is better than 𝜀>0, they both work! 𝜀=0 has a minor edge in larger scales (sparse gradients, faster assignment, slightly better metrics), but 𝜀>0 is also useful (faster SGD)

Thanks for the nice comments! my interpretation is that we're using OT to produce pairs (x_i,y_i) to guide FM. With that, it's up to you to provide an inductive bias (a model) that gets f(x)~=y while generalizing. The hard OT assignment could be that model, but it would fail to generalize.

for people that like OT, IMHO the very encouraging insight is that we have evidence that the "better" you solve your OT problem, the more flow matching metrics improve, this is Figure 3

Thanks @rflamary.bsky.social! yes, exactly. We try to summarize this tradeoff in Table 1, in which we show that for a one-off preprocessing cost, we now get all (noise,data) pairings you might need during flow matching training for "free" (up to the MIPS lookup for each noise).

Flow Matching with Semidiscrete Couplings Flow models parameterized as time-dependent velocity fields can generate data from noise by integrating an ODE. These models are often trained using flow matching, i.e. by sampling random pairs of noi...

the paper is out: arxiv.org/abs/2509.25519

Michal also did a fantastic push to open source the semidiscrete solver prepared by Stephen and Alireza in the OTT-JAX library. We plan to open source the flow pipeline in JAX soon. Please reach out if interested!

This much faster than using Sinkhorn, and generates with higher quality.

As a bonus, you can forget about entropy regularization (set ε=0), apply things like correctors to guidance, and use it on consistency-type models, or even with conditional generation.

the great thing with SD-OT is that this only needs to be computed once. You only need to store a real number per data sample. You can precompute these numbers once & for all using stochastic convex optimization.

When training a flow model, you assign noise to data using these numbers.

In practice, however, this idea only begins to work when using massive batch sizes (see arxiv.org/abs/2506.05526). The problem is that the costs of running Sinkhorn on millions of points can quickly balloon...

Our solution? rely on semidiscrete OT at scales that were never considered before.

Our two phenomenal interns, Alireza Mousavi-Hosseini and Stephen Zhang @syz.bsky.social have been cooking some really cool work with Michal Klein and me over the summer.

Relying on optimal transport couplings (to pick noise and data pairs) should, in principle, be helpful to guide flow matching

🧵

The A recent paper from Apple researchers,

New Apple #ML Research Highlight: The "Super Weight:" How Even a Single Parameter can Determine an #LLM's Behavior machinelearning.apple.com/research/the...

you're right that the PCs' message uses space as a justification to accept less papers, but it does not explicitly mention that the acceptance rate should be lower than the historical standard of 25%. In my SAC batch, the average acceptance before their email was closer to 30%, but that's just me..

I see it a bit differently. The new system pushed reviewers aggressively to react to rebuttals. I think this is a great change, but this has clearly skewed results, creating many spurious grade upgrades. Now the system must be rebalanced in the other direction by SAC/AC for results to be fair..

scaling up the computation of optimal transport couplings to hundreds of thousands of 3k dimensional vectors made easy using sharding and OTT-JAX! check this notebook, it only takes a few lines of code thanks to JAX's native sharding abilities ott-jax.readthedocs.io/en/latest/tu...

FastVLM: Efficient Vision Encoding for Vision Language Models Vision Language Models (VLMs) enable visual understanding alongside textual inputs. They are typically built by passing visual tokens from a…

New Apple #ML Research Highlight: "FastVLM: Efficient Vision Encoding for Vision Language Models" machinelearning.apple.com/research/fas...

So pleased and proud to share with you what our team has been up to, on an ambitious journey to build a video foundation model for scientific domains ! ✨ 🚀 🎞️ 🧪 #ICCV2025 #AI4Science

Standard error of what now? The NeurIPS checklist corroborates the bureaucratic theory of statistics.

The NeurIPS paper checklist corroborates the bureaucratic theory of statistics.

Can LLMs access and describe their own internal distributions? With my colleagues at Apple, I invite you to take a leap forward and make LLM uncertainty quantification what it can be.
📄 arxiv.org/abs/2505.20295
💻 github.com/apple/ml-sel...
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Shun-ichi Amari | Kyoto Prize Shun-ichi Amari

www.kyotoprize.org/en/laureates...

甘利 俊一 栄誉研究員が「京都賞」を受賞 甘利 俊一栄誉研究員（本務：帝京大学 先端総合研究機構 特任教授）は、人工ニューラルネットワーク、機械学習、情報幾何学分野での先駆的な研究が評価され、第40回（2025）京都賞（先端技術部門　受賞対象分野：情報科学）を受賞しました。

Shunichi Amari has been awarded the 40th (2025) Kyoto Prize in recognition of his pioneering research in the fields of artificial neural networks, machine learning, and information geometry

www.riken.jp/pr/news/2025...

NEW PAPER ALERT: Recent studies have shown that LLMs often lack robustness to distribution shifts in their reasoning. Our paper proposes a new method, AbstRaL, to augment LLMs’ reasoning robustness, by promoting their abstract thinking with granular reinforcement learning.

Now that @interspeech.bsky.social registration is open, time for some shameless promo!

Sign-up and join our Interspeech tutorial: Speech Technology Meets Early Language Acquisition: How Interdisciplinary Efforts Benefit Both Fields. 🗣️👶

www.interspeech2025.org/tutorials

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