paperlist.ai

AI conference papers

AI conference paper library

Search papers from 30+ top conferences, including NeurIPS, ICLR, ICML, CVPR, ACL and AAAI. Filter by keyword, then open any paper for its abstract, authors and links.

NeurIPS 2026

Policy-Level Exploration for Coordinated Multi-Agent Reinforcement Learning

Yucong Zhang, Chao Yu

In multi-agent reinforcement learning (MARL), agents must not only discover high-reward behaviours but also reliably reproduce coordinated behaviours over time. A fundamental challenge arises from a mismatch between action-level stochastic exploration and temporally extended coordination. To address this issue, we propose a policy-level exploration framework with Deterministic Action Execution (DAE) for MARL, which shifts locally random action exploration to temporally extended policy selection via an option-based exploration mechanism. Specifically, at each time step, each agent selects a policy from a shared policy set\textemdash comprising one exploitation policy and multiple exploration policies\textemdash using a learned option policy, and actions are executed deterministically conditioned on the selected policy. By maintaining deterministic execution under temporally extended policy selection, DAE facilitates temporally coordinated behaviours across multiple time steps. Comprehensive experiments on four multi-agent tasks\textemdash Predator Prey, StarCraft II micro management challenge (SMAC), SMACv2, Google Research Football, and Multi-Agent Coordination benchmark (MACO)\textemdash demonstrate that DAE outperforms mainstream baselines, achieving superior sample efficiency and final learning performance.

NeurIPS 2026

Policy-DRIFT: Dynamic Reward-Informed Flow Trajectory Steering

Atharva Mahajan, Abhijeet Yashwant Vishwasrao, Yuning Wang, Ricardo Vinuesa

Skin-friction drag induced by wall-bounded turbulent flows accounts for a substantial fraction of energy consumption across commercial aerospace, wind energy, and marine transport. Its active reduction is one of the highest-value targets in engineering fluid dynamics. Deep reinforcement learning (DRL) has emerged as the leading approach for real-time flow control, yet its performance ceiling is set not by algorithmic capability but by reward structure, the naive scalar objective does not optimally reflect the underlying physics. Policy-DRIFT bypasses this ceiling by relocating reward information from policy gradients to generative model inference: a conditional flow matching model (CFM) constructs a physically-grounded manifold of realisable flow states spanning multiple control regimes, Terminal Reward Guidance (TRG) steers samples toward reward-maximising targets at inference, and a lightweight DRL policy, structurally decoupled from reward quality, tracks these full-field targets via root-mean-squared error (RMSE) minimisation. The test case is turbulent channel flow simulated using direct numerical simulation (DNS) at friction Reynolds number of $\mathrm{Re}_\\tau = 180$, which is the canonical benchmark for wall-bounded turbulence. Policy-DRIFT achieves $49\\%$ drag reduction approaching the theoretical upper bound, which is $\\approx 16\\%$ higher than the DRL benchmark, while consuming 37$\\times$ less actuation energy. Our approach combines generative methods with active flow control, marking a paradigm shift towards controlling complex physical systems efficiently.

NeurIPS 2026

Policy Regret Minimization in Partially Observable Markov Games

Lan Sang, Raman Arora, Thanh Nguyen-Tang

We study policy regret minimization in partially observable Markov games (POMGs) between a learner and a strategic adaptive adversary who adapts to the learner's past strategies. We develop a model-based optimistic framework that operates on the learner-observable process using *joint* MLE confidence set and introduce an Observable Operator Model-based causal decomposition that disentangles the coupling between the world and the adversary model. Under multi-step weakly revealing observations and a bounded-memory, stationary and posterior-lipschitz adversary and planner stability, we prove an $\mathcal{O}(\sqrt{T})$ policy regret bound. This work advances regret analysis from Markov games to POMGs and provides the first policy regret guarantee under imperfect information against an adaptive opponent.

NeurIPS 2026

Policy Optimization in Tabular MDPs: Data-dependent Regret under Unknown Transitions

Mingyi Li, Taira Tsuchiya, Kenji Yamanishi

We study policy optimization for online episodic tabular Markov decision processes with unknown transition kernels, aiming for best-of-both-worlds guarantees and multiple data-dependent regret bounds. Recent work (Dann et al., 2023; Li et al., 2026) has shown that policy optimization can adapt to both adversarial and stochastic losses with data-dependent bounds, including first-order, second-order, and path-length bounds, but only under known transitions. We resolve the open problem raised by Dann et al. (2023) by developing optimistic follow-the-regularized-leader algorithms that extend such guarantees to unknown transitions. The key ingredient is a new design of optimistic $Q$-function estimators together with a data-dependent transition bonus that controls estimator bias through the loss-prediction error. Our analysis further identifies an unavoidable transition-dependent complexity term that captures the intrinsic cost of estimating the transition kernel. As a result, we obtain first-order, second-order, and path-length bounds with this transition-dependent complexity term while simultaneously achieving gap-dependent $\mathrm{polylog}(T)$ regret in the stochastic regime.

NeurIPS 2026

Policy Gradient Algorithms in Average-Reward Multichain MDPs

Jongmin Lee, Ernest Ryu

While there is an extensive body of research analyzing policy gradient methods for discounted cumulative-reward MDPs, prior work on policy gradient methods for average-reward MDPs has been limited, with most existing results restricted to ergodic or unichain settings. In this work, we first establish a policy gradient theorem for average-reward multichain MDPs based on the invariance of the classification of recurrent and transient states. Building on this foundation, we develop refined analyses and obtain a collection of convergence and sample-complexity results that advance the understanding of this setting. In particular, we show that the proposed $\alpha$-clipped policy mirror ascent algorithm attains an $\epsilon$-optimal policy with respect to positive policies.

NeurIPS 2026

Polestar: Drift-Aware Cache Calibration and Token Commitment for Efficient Inference of Diffusion LLMs

Mingyu Lee, Akshat Ramachandran, Souvik Kundu, Tushar Krishna

The inference efficiency of diffusion large language models (dLLMs) is constrained by two challenges: bidirectional attention precludes efficient KV-cache reuse, while increasing decoding parallelism with static confidence thresholds can compromise generation quality. We observe that both challenges arise from a shared phenomenon: as tokens are decoded, their contextual integration through bidirectional attention causes token representations to drift (evolve) across decoding steps. This insight motivates Polestar, a training-free inference framework that uses token representation drift as a unified signal to jointly address both challenges. Polestar comprises two components: Polestar-Cache, which identifies stale KV-cache positions via drift and performs sparse KV-cache refreshes to enable efficient reuse, and Polestar-Commit, which detects sharp drift events to reliably identify commit-ready tokens. Across mathematics and coding benchmarks on several dLLM families, Polestar sets a new state of the art on the accuracy-throughput Pareto frontier, achieving up to 10.73% accuracy improvement, up to 3.7x higher throughput, and high decoding parallelism of 3.67 tokens per forward pass over existing baselines.

NeurIPS 2026

PolarScale: A Physics-Grounded Benchmark for Radiometrically Consistent RGB-to-Stokes Estimation

Beibei Lin, Tingting Chen, Xin Zhang, Wenhao Zhao, Dongjun Li, Zifeng Yuan

Polarization imaging provides rich physical cues beyond RGB imaging, yet acquiring such information typically requires specialized polarization-sensitive hardware that increases system cost and deployment complexity. Recent methods have proposed to infer polarization information directly from standard RGB images, providing a hardware-free alternative. While useful for describing relative polarimetric structure, these representations do not fully assess whether estimated images preserve the radiometric scale and intensity-dependent physical information needed for full Stokes reconstruction. To address this limitation, we introduce PolarScale, a physics-grounded benchmark for radiometrically consistent RGB-to-Stokes estimation. Instead of treating polarization inference from RGB images as conventional image-to-image translation, PolarScale evaluates how scale-independent descriptors, scale-dependent Stokes components, and radiometric scale jointly support physically meaningful Stokes reconstruction. Building upon this formulation, we propose three prediction strategies, namely direct, joint, and decoupled prediction, to study how scale-independent and scale-dependent polarimetric cues should be modeled across representative restoration-based and generative frameworks. Our analysis reveals that restoration-based frameworks outperform generative ones for radiometrically consistent polarization estimation (e.g., 28.61 vs. 26.14 dB PSNR). Furthermore, we find that jointly modeling scale-independent and scale-dependent parameters yields more stable physical representations than direct scale-dependent prediction (e.g., 28.61 vs. 26.81 dB PSNR). Overall, PolarScale provides a physics-grounded benchmark foundation for evaluating whether vision models can recover radiometrically consistent polarimetric signals from standard RGB images.

NeurIPS 2026

Polar Transformers: $SO(2)^K$-Equivariant Angular Attention for Cryo-EM Image-Set Processing

Joakim Andén, Justus Sagemüller

Many projection-based imaging modalities reconstruct unknown objects from collections of noisy projections related by unknown in-plane rotations, making effective estimation dependent on rotationally consistent alignment and aggregation. In cryogenic electron microscopy (cryo-EM), the extremely low signal-to-noise ratio (SNR) makes such multi-image integration essential. We introduce the *polar transformer*, a permutation-invariant architecture for *sets* of images built around an $\mathrm{SO}(2)^K$-equivariant *angular attention* mechanism that jointly aligns and aggregates information across images. This architecture leverages a stable polar representation in which we define polar CNN feature extractors and evaluate attention weights over all relative angular shifts efficiently via FFT-based correlations, guaranteeing equivariance to independent in-plane rotations of each image in the set. We evaluate the polar transformer on simulated cryo-EM images using denoising as a quantitative proxy. Across different regimes, polar transformers outperform strong single-image and image-set baselines, achieving a reduction of up to 40% in relative MSE at an SNR of 0.02 and improving downstream ab initio reconstruction resolution by 20%.

NeurIPS 2026

Poisoning Attacks on LLMs Require a Near-constant Number of Poison Samples

Alexandra Souly, Javier Rando, Ed Chapman, Xander Davies, Burak Hasircioglu, Ezzeldin Shereen, Carlos Mougan, Vasilios Mavroudis, Erik Jones, Chris Hicks, Nicholas Carlini, Yarin Gal, Robert Kirk

Poisoning attacks can compromise the safety of large language models (LLMs) by injecting malicious documents into their training data. Existing work has studied pretraining poisoning assuming adversaries control a percentage of the training corpus. However, for large models, even small percentages translate to impractically large amounts of data. This work demonstrates for the first time that poisoning attacks instead require a near-constant number of documents regardless of dataset size. We conduct the largest pretraining poisoning experiments to date, pretraining models from 600M to 13B parameters on chinchilla-optimal datasets (6B to 260B tokens). We find that 250 poisoned documents similarly compromise models across all model and dataset sizes, despite the largest models training on more than 20 times more clean data. We also run smaller-scale experiments to ablate factors that could influence attack success, including broader ratios of poisoned to clean data and non-random distributions of poisoned samples. Finally, we demonstrate the same dynamics for poisoning during fine-tuning. Altogether, our results suggest that injecting backdoors through data poisoning may be easier for large models than previously believed as the number of poisons required does not scale up with model size—highlighting the need for more research on defences to mitigate this risk in future models.

NeurIPS 2026

Poison-then-Hide: Finetuning-Activated Backdoor Attack on Pretrained Vision Encoders

Qixuan Jin, Abinitha Gourabathina, Vinith Suriyakumar, Walter Gerych, Marzyeh Ghassemi

Backdoor attacks threaten the integrity of machine learning models by allowing attackers to control model behavior through triggers. Models can be compromised during finetuning by backdoor attacks through either poisoned data or adversarial training objectives. Because existing finetuning-activated attacks assume limited domain shift or frozen encoder layers, they often fail under full-model finetuning. We target a stealthy finetuning-activated attack where a dormant backdoor is implanted in a pretrained encoder, and later activated by finetuning on clean downstream data. We propose Poison-then-Hide, a novel attack that remains effective when the entire model is finetuned in a domain transfer. Our approach consists of three components: trigger optimization, base encoder poisoning, and targeted unlearning to conceal the backdoor. We evaluate our method on six datasets and three model architectures, and achieve state-of-the-art (up to 97%) attack success rates. We find that two design choices - jointly learning the benign target task and the backdoor during encoder poisoning, and optimizing the trigger for attack robustness using an ensemble of simulated finetuned models - are critical to the attack's success. We demonstrate that standard detection and mitigation defenses cannot fully remove the backdoor, which can reappear after benign finetuning.

NeurIPS 2026

Pointwise Lipschitz Continuous Graph Algorithms

Quanquan C. Liu, Grigoris Velegkas, Yuichi Yoshida, Felix Zhou

In many real-world applications, it is undesirable to drastically change the problem solution after a small perturbation in the input as unstable outputs can lead to costly transaction fees, privacy and security concerns, reduced user trust, and lack of replicability. Despite the widespread application of graph algorithms, many classical algorithms are not robust to small input disturbances. Towards addressing this issue, we study the pointwise Lipschitz continuity of graph algorithms, a notion of stability introduced by Kumabe and Yoshida (2023, FOCS’23) and further studied in related settings (Kumabe and Yoshida, 2024, ICALP’24), (Kumabe and Yoshida, 2025, SODA’25), (Gima et al., 2025, ESA’25). Our main result is a linear programming (LP) based minimum S-T cut algorithm with a provably optimal Lipschitz constant, as witnessed by an accompanying lower bound. As a direct corollary, we give the first dynamic minimum S-T cut algorithm with non-trivial recourse bound. At the core of our techniques is a novel framework for analyzing the Lipschitz constant of regularized LP relaxations. Our framework crucially unlocks the use of weighted regularizers, which could not be analyzed through previous methods and leads to polynomial improvements in the Lipschitz constant compared to what is achievable through previous techniques. To demonstrate the flexibility of our methods, we also design an LP-based b-matching algorithm that improves on the state-of- the-art Lipschitz constant in certain input regimes when b ≡ 1. Moreover, our algorithm cleanly extends to the general case when b ≥ 1, whereas prior works are specialized to the case of b ≡ 1.

NeurIPS 2026

PointZero: 3D Point Track Completion for Learning Transferable 3D Dynamics

Bardienus Duisterhof, Kaifeng Zhang, Adam Hung, Bowen Wen, Stan Birchfield, Yunzhu Li, Deva Ramanan, Jeffrey Ichnowski

World models endow perceptual systems with the ability to predict how scenes evolve under interaction. They are most beneficial when trained on diverse volumes of data, to instill a rich prior into downstream applications. Existing methods for capturing 3D world models are typically scene-specific dynamics models, or require robot action labels - which excludes web video data from the training pool. We study 3D point track completion as a pre-trianing objective for learning transferable 3D dynamics without robot data. Given a single RGB-D observation and sparse partial 3D trajectories (tracks), we predict future 3D tracks of all observed points. We show this is a objective provides a rich dynamics prior, without requiring robot action labels. We contribute a diverse dataset of 2.9 million synthetic frames spanning deformable, articulated, and rigid objects, and use it to train PointZero. We show that a flexible and expressive transformer, PointZero, outperforms prior methods on the same data. We demonstrate the utility of our pre-training objective by fine-tuning PointZero for two downstream applications: (1) action-conditioned dynamics and (2) robot manipulation. When fine-tuned to condition on end-effector pose, PointZero outperforms the baselines on a recent action-conditioned 3D dynamics benchmark. When fine-tuned to predict robot actions, PointZero outperforms or matches the baselines on 6/7 simulated and real-world robot manipulation tasks. We furthermore evaluate training PointZero from scratch to isolate the benefits of our proposed architecture from those of our proposed pre-training objective and dataset. We release the dataset, model checkpoints, and full training recipe.

NeurIPS 2026

Point4D: Long-range 4D Motion Reconstruction

Minsik Jeon, Jay Karhade, Deva Ramanan, Shubham Tulsiani

We introduce Point4D, a feed-forward model for 4D reconstruction of long-range video sequences. Point4D is able to reliably infer dense per-point 3D trajectories across multi-hundred video sequences, unlike existing 4D methods that are limited to short input windows of at most a few dozen frames. A key innovation that enables this is our flexible 3D query-based motion decoder that decouples trajectory prediction from image-plane visibility. The predicted 3D endpoints are then directly re-queried in the next chunk without re-projection or matching. Furthermore, we show that extracting and reusing a visual across an arbitrary frame where the point is visible leads to superior performance than purely relying on the source patch. Overall, Point4D achieves state-of-the-art performance across diverse long-video tracking benchmarks spanning over 200 frames and substantially outperforms previous feed-forward 4D methods.

NeurIPS 2026

Point-to-Manifold Geometry: Flexibly Overcoming the Curse of Dimensionality in Neural Computational Units

Rohan Ghosh, Mehul Motani

The ability of neural networks to generalize is fundamentally shaped by their computational units. While the perceptron provides a first-order, linear inductive bias and the radial basis function (RBF) unit offers an isotropic curved bias, we identify a critical opportunity for a structured extension: the Generative Matching Unit (GMU). Each individual GMU captures complex dependencies by treating the forward pass as an inference problem; its internal generative model optimizes instance-specific latent parameters to compute a reconstruction error, effectively measuring a point-to-manifold distance as opposed to the point-to-point distance in RBFs. We focus on linear GMUs, which yield closed-form analytical expressions for fast computation and extend naturally to convolutional architectures. Our theoretical analysis demonstrates that linear GMUs are highly flexible universal approximators capable of recovering structured class posteriors. We prove that while a single GMU can exactly emulate an RBF kernel and two can emulate the decision boundary of a perceptron, emulating a single $k$-order GMU’s decision boundary requires a hidden layer of standard units that scales polynomially or exponentially with input dimensionality. Furthermore, we prove that the GMU’s point-to-manifold distance remains discriminative in high dimensions where standard Euclidean distances fail, offering unique robustness to the curse of dimensionality. Finally, we show that GMUs offer superior flexibility and efficiency in learning smooth manifold decision boundaries compared to MLPs and RBFs. Motivated by the theoretical results, we place GMUs in the first network layer like RBFs, where their role is to enhance linear separability for subsequent layers. This avoids the typical gradient collapse problem with stacking RBF-like units while ensuring the generalization benefits remain. We find that across extensive experiments involving 27 tabular datasets, five vision datasets evaluated across 34 test-time corruption settings, and 30 synthetic scenarios, GMU networks demonstrate statistically significant improvements in generalization and robustness.

NeurIPS 2026

Point Tracking Improves World Action Models

Jiarui Guan, Wenshuai Zhao, Yue Pei, Ziliang Chen, Arno Solin, Juho Kannala

Robot policy learning benefits from world-action models that capture environment dynamics, but pixel-level prediction entangles dynamics with nuisance factors such as lighting and texture, making learned representations vulnerable to task-irrelevant visual variation. We propose JOPAT, a JOint Pixel-And-Track World-Action Model that predicts latent visual observations, 2D point tracks with visibility, and actions in a single denoising diffusion transformer. The key insight is that tracks provide an explicit representation of motion that captures long-horizon dynamics and remains robust under occlusion or partial out-of-frame motion, offering greater utility than modeling pixel appearance alone. On LIBERO and real-world LeRobot tasks, JOPAT improves over pixel-based baselines, with the largest gains on long-horizon tasks involving occlusion, object interaction, and off-screen motion.

NeurIPS 2026

Point Clustering Encoders

Evangelos Chatzipantazis, Guillem Braso, Cristiano Saltori, Sérgio Agostinho, Kostas Daniilidis, Aljosa Osep, Laura Leal-Taixé

Learning expressive and transferable representations from unstructured 3D data remains a fundamental challenge. Existing backbones mirror the design of image-based networks by relying on symmetric U-Net architectures with large parametric decoders and feature skip connections. While successful in 2D, these designs are ill-suited for 3D domain where point coordinates, that define the underlying geometric manifold on which feature representations are learned, are sensitive to sensor-specific sampling patterns. In such architectures, skip connections allow low-level coordinate cues to bypass the semantic bottleneck, leading the model to overfit to local spatial patterns rather than learning robust, transferable semantic abstractions. We re-think this design and introduce Point Clustering Encoders (PCE), a minimal, decoder-free network that treats point cloud processing as a hierarchy of end-to-end learned spatial supertokens. At the core of PCE is our Time-Reversible Attention Pooling (TRAP) layer, which formalizes hierarchical downsampling as a time-reversible Markov chain. By coupling upsampling to the reverse chain, we eliminate the need for traditional decoders; the task of representation learning is fully delegated to the encoder. PCE not only surpasses state-of-the-art w.r.t. segmentation accuracy in indoor/outdoor datasets across a variety of tasks, but also reduces the number of trainable parameters, and can process scenes consisting of up to 6.5M points.

NeurIPS 2026

Point Cloud Sequence Encoding for Material-conditioned Graph Network Simulators

Philipp Dahlinger, Balazs Gyenes, Niklas Freymuth, Luca Geminiani, Tobias Würth, Johannes Mitsch, Nadja Klein, Luise Kärger, Gerhard Neumann

Graph Network Simulators (GNS) have emerged as powerful surrogates for complex physics-based simulation, offering inherent differentiability and orders-of-magnitude speedups over traditional solvers. However, GNSs typically assume access to the underlying material parameters, such as stiffness or viscosity, severely limiting their utility in realistic experimental settings. While recent meta-learning approaches address the parameter dependency by inferring properties from mesh trajectories, reconstructing a mesh from an observed scene is difficult. In this work, we introduce Point Cloud Encoding for Accurate Context Handling (PEACH), a novel framework that applies in-context learning on point clouds to adapt a learned simulator to unseen physical properties during inference. Our approach relies on a novel spatio-temporal point cloud sequence encoder, as well as two forms of auxiliary supervision to help improve simulation fidelity. We demonstrate that PEACH is capable of accurate zero-shot sim-to-real transfer on a challenging, dynamic scene. Experiments on simulation scenes show that PEACH even outperforms mesh-based baselines on simulation accuracy, while being much more practical for real-world deployment.

NeurIPS 2026

PoSafeNet: Structured Safety Learning via Compositional Projection

Kiwan Wong, Wei Xiao, Daniela Rus

Safe robot learning often involves multiple heterogeneous safety constraints that cannot always be satisfied simultaneously. Existing neural safety layers typically treat multi-constraint safety as a numerical optimization problem, enforcing all constraints through a single QP-based projection or relaxing conflicts with slack variables. This hides the semantic question of which constraints may be sacrificed under conflict inside solver geometry, penalty weights, or a fixed total hierarchy. We propose PoSafeNet, a poset-structured composable safety layer that makes these conflict semantics explicit. PoSafeNet encodes admissible safety override relations as a partial order and realizes each admissible execution by composing closed-form projections onto CBF-induced halfspaces. Across multi-obstacle navigation, constrained manipulation, and vision-based autonomous driving, PoSafeNet improves operational feasibility, computational efficiency, and task performance over dQP-based, slack-based, and hierarchical safety layers.

NeurIPS 2026

PoEM: Predicting New RL Outcomes from Existing Policies

Kimia Hamidieh, Giannis Daras, Antonio Torralba

Pre-trained models are routinely post-trained with reinforcement learning (RL) to maximize specific rewards, such as human alignment, correctness, or instruction following. This post-training process is computationally intensive, sometimes unstable, and has to be run from scratch every time the reward model changes or when we want to combine multiple rewards. We hence ask: given a new reward function, is it possible to predict the RL outcomes without actually running RL on it? We answer this in the affirmative by introducing PoEM, a framework to predict the outputs of RL on a new reward function using a set of models already post-trained on other rewards. First, we show that if the new reward function can be written as a linear combination of existing ones, then the new policy in log-space can be written as a linear combination of the existing log-policies. Surprisingly, even in cases where the rewards are not linearly connected, we observe that often log-policies from RL training span an approximately low-rank subspace across rewards. To our benefit, the weighting coefficients for this combination can be estimated using only the reward or basis policy outputs on the samples. We turn these observations into an algorithm that takes post-trained models and a new reward function, and approximates the target RL policy without actually running any additional RL training. We experimentally validate our approach across synthetic and real experiments, spanning both text and image modalities.

NeurIPS 2026

Plug-and-Play ADMM for Inverse Problems with Flow Matching Denoiser

Dibyanshu Kumar, Magda Gregorova

Plug-and-Play (PnP) methods with generative priors have achieved strong performance in inverse problems, with recent flow matching models enabling fast and scalable reconstruction. However, a key challenge in PnP methods is maintaining consistency between data fidelity updates and the learned generative prior, as data-consistency steps can move iterates away from the flow trajectory. We propose an ADMM-based PnP framework for flow matching priors that enforces stronger consistency between the measurement model and the prior through auxiliary variables and dual updates. In addition, we introduce a trajectory correction mechanism that restores consistency with the flow via a combination of deterministic and stochastic projections. Our method provides a more principled integration of flow priors within PnP frameworks, achieving high-quality reconstructions with reduced computational cost.

Keep browsing

More papers from top AI conferences

30+ top conferences, by conference, year, and topic.