collaborators

8 papers

cs.CL2026

ABBA-Adapters: Efficient and Expressive Fine-Tuning of Foundation Models

Raghav Singhal, Kaustubh Ponkshe, Rohit Vartak +1

Large Language Models have demonstrated strong performance across a wide range of tasks, but adapting them efficiently to new domains remains a key challenge. Parameter-Efficient F…

cs.LG2026

Safety Subspaces are Not Linearly Distinct: A Fine-Tuning Case Study

Kaustubh Ponkshe, Shaan Shah, Raghav Singhal +1

Large Language Models (LLMs) rely on safety alignment to produce socially acceptable responses. However, this behavior is known to be brittle: further fine-tuning, even on benign o…

cs.CL2025

Apertus: Democratizing Open and Compliant LLMs for Global Language Environments

Project Apertus, Alejandro Hernández-Cano, Alexander Hägele +100

We present Apertus, a fully open suite of large language models (LLMs) designed to address two systemic shortcomings in today's open model ecosystem: data compliance and multilingu…

cs.LG2025

Fed-SB: A Silver Bullet for Extreme Communication Efficiency and Performance in (Private) Federated LoRA Fine-Tuning

Raghav Singhal, Kaustubh Ponkshe, Rohit Vartak +2

Low-Rank Adaptation (LoRA) has become ubiquitous for efficiently fine-tuning foundation models. However, federated fine-tuning using LoRA is challenging due to suboptimal updates a…

cs.CL2025

Initialization using Update Approximation is a Silver Bullet for Extremely Efficient Low-Rank Fine-Tuning

Kaustubh Ponkshe, Raghav Singhal, Eduard Gorbunov +3

Low-rank adapters have become standard for efficiently fine-tuning large language models, but they often fall short of achieving the performance of full fine-tuning. We propose a m…

math.NA2025

Jacobian-Free Newton-Krylov with a globalization method for solving groundwater flow models of multi-layer aquifer systems

Raghav Singhal, Emin Can Dogrul, Zhaojun Bai

A Jacobian free Newton Krylov (JFNK) method with a globalization scheme is introduced to solve large and complex nonlinear systems of equations that arise in groundwater flow model…