The research arm of AI Wranglers

We find the optimum, and we care where it leads.

optimal* lab works where optimization meets machine learning, and points both at one question: how do we build AI that is safe, trustworthy and aligned with the people it serves? Our long-term mission is a safe and humane planet for all.

20+
papers at CORE A/A* venues
43
publications
5
papers at NeurIPS 2026
2026
EMNLP · AAMAS · SDM · CVPR-W · ACL-W · RSS-W

optimal*

Optimization · Machine Learning

  1. SSafetySystems that fail gracefully, and never in ways that hurt.
  2. TTrustworthinessModels whose behaviour holds up under scrutiny and shift.
  3. AAlignmentDoing what people actually intend, not merely what was optimised.
  4. RResearchRigorous, open and built on mathematics that lasts.

Research highlights

Recent work, told as stories

Pick a theme to see the work behind it. The same filter applies to every publication below.

Diffusion language models EMNLP 2026 · Main

TAP: Policy Interfaces for Diffusion Language Models

Diffusion language models do not write left to right: they refine a whole draft over many denoising steps. TAP asks how a policy should interface with that process, and proposes policy interfaces built for it.

Diffusion ModelsLanguage ModelsAlignment
Full story, figures and video: in production

Safe multi-agent planning AAMAS 2026

MA-SafeDiffuser: Safe Multi-Agent Planning with Diffusion Probabilistic Models

Several agents plan together by denoising their trajectories with a diffusion model, with safety treated as part of the plan rather than a check bolted on afterwards.

SafetyMulti-agentDiffusion ModelsRobotics
Full story, figures and video: in production

Safe offline RL AAMAS 2026

Safe Offline Reinforcement Learning using Diffusion Policies

Learning to act safely from logged experience alone, with no risky trial and error in the world, using diffusion models as expressive policies.

SafetyReinforcement LearningDiffusion Models
Full story, figures and video: in production

Vision-language alignment CVPR 2026 · VisCon

ConceptOT: Fine-Grained Vision-Language Alignment via Low-Rank Unbalanced Optimal Transport

Matching image regions to the words that describe them as an optimal transport problem: low-rank and unbalanced, so fine-grained concepts find their partners. A companion paper anchors visual concepts at test time with entropic OT.

VisionAlignmentOptimal Transport
Full story, figures and video: in production

World models for robots RSS 2026 · Workshop

A Planner-Centered Study of Robust Latent World Models

A robot that plans inside a learned world model is only as safe as that model is robust. This study judges latent world models by what matters to the planner that relies on them.

World ModelsRoboticsRobustness
Read the paperFull story, figures and video: in production

Optimization on manifolds SIAM J. Optimization 2023

Riemannian Hamiltonian Methods for Min-Max Optimization on Manifolds

Min-max problems, the mathematics behind adversarial training and robust learning, posed on curved spaces and solved with Riemannian Hamiltonian methods.

OptimizationRobustness
Full story, figures and video: in production

Publications

Selected publications

2026

  1. TAP: Policy Interfaces for Diffusion Language Models

    Preeti, A. Kushwaha, K. Ravish, P. Kumar

    EMNLP 2026Main Conference

  2. Quantizing Masked Diffusion Language Models: What Compresses, What Breaks, and What Transfers

    N. Mishra, P. Kumar

    EMNLP 2026Industry Track

  3. MA-SafeDiffuser: Safe Multi-Agent Planning with Diffusion Probabilistic Models

    K. Ravish, et al.

    AAMAS 2026

  4. Safe Offline Reinforcement Learning using Diffusion Policies

    A. Kushwaha, et al.

    AAMAS 2026

  5. Discrete Diffusion Language Models Are Training-Free Multi-Label Classifiers

    P. Kumar

    SDM 2026SIAM International Conference on Data Mining

  6. Test-Time Visual Concept Anchoring via Entropic Optimal Transport

    P. Kumar

    CVPR 2026 WorkshopVisCon

  7. ConceptOT: Fine-Grained Vision-Language Alignment via Low-Rank Unbalanced Optimal Transport

    P. Kumar

    CVPR 2026 WorkshopVisCon

  8. Speculative Refinement: A Hybrid Autoregressive Diffusion Decoding Strategy and Its Behavior Across Benchmarks

    A. Gupta, N. Mishra, K. Trivedi, P. Kumar

    ACL 2026 WorkshopGEM

  9. Semantically Aware Optimal Transport for Dense Label Transfer

    Preeti, et al.

    ACL 2026 WorkshopALVR

  10. Stable 3D Tokens for Foundation-Model Robot Planning

    P. Kumar

    RSS 2026 WorkshopRobot Planning in the Era of Foundation Models

  11. A Planner-Centered Study of Robust Latent World Models

    P. Kumar

    RSS 2026 WorkshopRobot Planning in the Era of Foundation Models

2025

  1. Alignment and Safety of Diffusion Models via Reinforcement Learning and Reward Modeling: A Survey

    P. Lamba, et al.

    arXiv 2025under submission

  2. A Survey of Safe Reinforcement Learning and Constrained MDPs: A Technical Survey on Single-Agent and Multi-Agent Safety

    A. Kushwaha, et al.

    arXiv 2025under submission

  3. Hierarchical Sparse Plus Low Rank Compression of LLM

    A. Gupta, et al.

    CODS 2025

  4. Fast and Efficient Modern BERT based Text-Conditioned Diffusion Model for Medical Image Segmentation

    Siddharth, et al.

    CVIP 2025

2024

  1. A Gauss-Newton Approach for min-max Problem in GAN

    N. Mishra, P. Jawanpuria, B. Mishra, P. Kumar

    IJCNN 2024

  2. Review of Extreme Multilabel Classification

    A. Dasgupta, S. Katyan, S. Das, P. Kumar

    arXiv 2024

  3. Qualitative Data Augmentation for Performance Prediction in VLSI circuits

    P. Srivastava, P. Kumar, Z. Abbas

    Integration, the VLSI Journal 2024Elsevier

  4. Data Augmentation for Performance Prediction in VLSI circuits

    P. Srivastava, P. Kumar, Z. Abbas

    ISCAS 2024

  5. A label-free sensing of creatinine using radio frequency-driven lab-on-chip (LOC) system

    S. Sinha, et al.

    Engineering Research Express 2024IOP Science

  6. A Label-Free Low-Cost Radio Frequency Driven Noninvasive Lab-on-Chip System for Creatinine Detection

    S. Sinha, et al.

    ICST 2024

2023

  1. Riemannian Hamiltonian methods for min-max optimization on manifolds

    A. Han, et al.

    SIAM J. Optimization 2023

  2. alphaElimination: Using deep reinforcement learning for sparse Gaussian Elimination

    A. Dasgupta, P. Kumar

    ECML 2023

  3. marl-jax: Multi-agent Reinforcement Learning framework for Social Generalization

    K. Mehta, A. Mahajan, P. Kumar

    ECML 2023

  4. Light-weight Deep Extreme Multilabel Classification

    I. Mishra, A. Dasgupta, B. Mishra, P. Jawanpuria, P. Kumar

    IJCNN 2023Best Paper Award

  5. Effects of Spectral Normalization in Multi-agent Reinforcement Learning

    K. Mehta, A. Mahajan, P. Kumar

    IJCNN 2023

  6. Angle based dynamic learning rate for gradient descent

    N. Mishra, P. Kumar

    IJCNN 2023

  7. Adaptive Consensus Optimization Method for GANs

    S. Danisetty, S. Mylaram, P. Kumar

    IJCNN 2023

  8. Enhancing ML model accuracy for Digital VLSI circuits using diffusion models

    P. Srivastava, Z. Abbas, P. Kumar

    NeurIPS 2023 Workshop

2022

  1. Hybrid Tokenization and Datasets for Solving Mathematics and Science Problems Using Transformers

    P. Mandlecha, et al.

    SDM 2022

  2. A Riemannian Approach to Extreme Classification Problems

    J. Naram, T. Sinha, P. Kumar

    CODS-COMAD 2022

  3. Nonnegative Low-Rank Tensor Completion via Dual Formulation with Applications to Image and Video Completion

    T. Sinha, J. Naram, P. Kumar

    WACV 2022

2021

  1. SCIMAT: Science and Mathematics Dataset

    S. Chatakonda, N. Kollepara, P. Kumar

    NeurIPS 2021 WorkshopDCAI

  2. Structured Low-Rank Tensor Learning

    J. Naram, T. Sinha, P. Kumar

    NeurIPS 2021 Workshop

  3. A Fast Parameter-Free Preconditioner for Structured Grid Problems

    A. Agarwal, S. Kakkar, P. Kumar

    SC 2021

  4. A Deflation Based Fast and Robust Preconditioner for Bundle Adjustment

    S. Das, et al.

    WACV 2021

  5. DXML: Distributed Extreme Multilabel Classification

    P. Kumar

    BDA 2021Springer

2020

  1. Multigrid Preconditioned Solver for Bundle Adjustment

    S. Katyan, et al.

    WACV 2020

2019

  1. Efficient FPGA Implementation of Conjugate Gradient Methods for Laplacian System using HLS

    FPGA 2019

2016

  1. Fast Preconditioned Solver for Truncated Saddle Point Problem in Nonsmooth Cahn-Hilliard Model

    Book chapter 2016

2015

  1. Multilevel Communication Optimal Least Squares Solver

    ICCS 2015

2013

  1. High Performance Solvers for Implicit Particle in Cell Simulation

    ICCS 2013

2010

  1. Modified tangential frequency filtering decomposition and its Fourier analysis

    Numerische Mathematik 2010

Roadmap

A living map of where our work sits

Each of our papers, the questions it answers, and the related work around it in the field, kept current as the field moves. The full interactive map is in development.

Coming soon
Optimization Diffusion models Language models World models · Robotics Multi-agent · RL Vision · OT

News

Lately

  1. Award

    Kiran Ravish named among the Top 100 ML Scientists in India by Amazon

    Kiran, a PhD student in the group, has publications at AAMAS, EMNLP and NeurIPS.

  2. NeurIPS

    Five papers accepted at NeurIPS 2026

    Across the Main Track and Workshops.

  3. EMNLP

    Two papers accepted at EMNLP 2026

    TAP in the Main Conference, and Quantizing Masked Diffusion Language Models in the Industry Track.

  4. AAMAS

    Two papers accepted at AAMAS 2026

    MA-SafeDiffuser, and Safe Offline Reinforcement Learning using Diffusion Policies.

  5. SDM

    Paper accepted at SIAM SDM 2026

    Discrete Diffusion Language Models Are Training-Free Multi-Label Classifiers.

  6. CVPR

    Two papers at the CVPR 2026 VisCon workshop

    ConceptOT, and Test-Time Visual Concept Anchoring via Entropic Optimal Transport.

  7. ACL

    Two papers at ACL 2026 workshops

    Speculative Refinement at GEM, and Semantically Aware Optimal Transport for Dense Label Transfer at ALVR.

  8. RSS

    Two papers at the RSS 2026 Robot Planning workshop

    Stable 3D tokens for foundation-model robot planning, and robust latent world models.

  9. Service

    ICML 2026 Silver Reviewer Award, and AAAI 2027 Program Committee

Portrait of Pawan Kumar

Head of the lab

Pawan Kumar

Pawan leads optimal* lab, with more than twenty publications at CORE A and A* venues across optimization, machine learning and AI safety. He did his PhD at INRIA, France (très honorable), followed by postdoctoral research at KU Leuven, Fraunhofer ITWM and FU Berlin, and is a researcher at IIIT Hyderabad, where he supervises PhD and Masters students.

Best Paper Award, IJCNN 2023 · ICML 2026 Silver Reviewer Award · Marie Curie Fellowship · Qualcomm Faculty Award