Curriculum Vitae

Researcher in reinforcement learning, generative modeling, LLM post-training and alignment, diversity, creativity, and interpretable AI.

First author of an ICML 2026 paper and Machine Learning PhD researcher at the National University of Singapore, developing reinforcement-learning post-training methods for generative models and language-model reasoning. Research spans policy optimization, reward-proportional generation, multimodal generation, and diversity/mode-collapse mitigation.

abhijeet@nus.edu.sg · Google Scholar · LinkedIn

Education

Aug 2024–Jul 2029 (expected)

PhD, Machine Learning

National University of Singapore, Singapore

  • Thesis: Diversity and Creativity in Generative AI
  • Supervisor: Dr. Dianbo Liu

Aug 2016–May 2021

Dual Degree (Bachelor's & Master's), Biotechnology

Indian Institute of Technology Madras, Chennai, India

Experience

Feb 2024–present

Research Assistant

Artificial Scientific Intelligence Lab, National University of Singapore, Singapore

  • Identified and characterized frequency amplification in expected-return optimization, then developed Inverse Probability Scaling (IPS) to recover reward-proportional terminal distributions under the analyzed dynamics; resulted in a first-author ICML 2026 paper.
  • Developed and implemented RL post-training in PyTorch/Hugging Face for set-valued causal, spatial, and symbolic reasoning with Gemma-3 4B; improved valid-outcome recovery from 16.0% to 43.9%, 31.6% to 90.0%, and 9.5% to 60.7% across experimental settings.
  • Designed multimodal RL pipelines in which Qwen3-0.6B/GPT-2 policies conditioned a frozen Stable Diffusion v1.4 generator; developed and evaluated CLIP/DINOv2-based density-aware reward scaling, improving Image Vendi score by 32–161% relative to GRPO across settings.
  • Extended the research program to larger outcome spaces through MIPS (under review at ICLR 2027), using trajectory-based marginal-probability estimation for massive discrete spaces, and DARS (under review at AAAI 2027), using density-aware reward scaling for continuous spaces.
  • Co-developed a mechanistic-interpretability study using CLIP ViT-L/14, sparse Matryoshka Transcoders, and LMM-based feature interpretation; evaluated physical-plausibility failure modes over 5,000 images per model.
  • Integrated density-aware reward scaling with GRPO for multimodal navigation and LLM-based text-to-image prompt adaptation.
  • Developed methods for LLM post-training and alignment, focused on reward design, diverse generation and reasoning-oriented evaluation.
  • Built an RL agent that edits discrete VQ-VAE latent codes using classifier-confidence and discriminator-realism feedback.

Aug 2023–Dec 2023

Machine Learning Engineer

VAO Labs, San Francisco, CA, USA

  • Built LayoutLM and OCR document-understanding pipelines for structured information extraction.
  • Fine-tuned T5-family models for document question answering and answer retrieval.
  • Built Llama-based applications for querying large enterprise datasets in natural language.

Apr 2022–Jul 2023

Research Assistant

Computational Neuroscience Lab, IIT Madras, Chennai, India

  • Designed a brain-inspired visual attention model that learns saccadic image-scanning policies for object counting with Q-learning and recurrent neural networks.
  • Co-invented a System for Monitoring Parkinson's Disease; patent granted to IIT Madras.
  • Developed computer-vision and reinforcement-learning systems for neurological healthcare applications.

Jun 2021–Dec 2021

Software Developer

IIFL, Mumbai, India

  • Developed full-stack software with ASP.NET, SQL Server, Angular, JavaScript and jQuery.
  • Integrated, tested and documented changes using TFS and Azure in an agile workflow.

Publications

Patents

A System for Monitoring Parkinson's Disease

Indian patent, granted to IIT Madras. Co-inventor. Certificate

Skills

Programming
Python, SQL, C/C++, JavaScript, R, Bash
ML & generative modeling
PyTorch, TensorFlow, Hugging Face Transformers, Stable Diffusion, CLIP, DINOv2, VQ-VAE, latent-variable models, representation learning
RL & LLMs
Policy-gradient RL, GRPO, reward design/scaling, RLHF, supervised fine-tuning, instruction tuning, LoRA/PEFT, 4-bit NF4, bfloat16, alignment, reasoning evaluation; Gemma, Qwen, Llama, GPT-2
Mechanistic interpretability
Sparse autoencoders, Matryoshka Transcoders
Applied AI
Stable-Baselines, RLlib, scikit-learn, OpenCV, FastAPI, Flask, OCR, document understanding
Experimentation & MLOps
Weights & Biases, MLflow, distributed training, Git, Docker, Linux, Google Cloud Platform