Conference Papers

• Fully-Succinct Multi-Key FHE & Rate-1 Simulatable Threshold Decryption from LWE

Abtin Afshar, Rishab Goyal

Crypto 2026

• Multi-Hop Multi-Key Homomorphic Signatures with Context Hiding from Standard Assumptions

Abtin Afshar, Jiaqi Cheng, Rishab Goyal,

PKC 2026

• On the (Im)possibility of Time-Lock Puzzles in the Quantum Random Oracle Model

Abtin Afshar, Kai-Min Chung, Yao-Ching Hsieh, Yao-Ting Lin, Mohammad Mahmoody,

Aciacrypt 2023

• Fine-Grained Non-Interactive Key-Exchange: Constructions and Lower Bounds

Abtin Afshar, Geoffroy Couteau, Mohammad Mahmoody, Elahe Sadeghi

Eurocrypt 2023

Preprints and Manuscripts

• Multi-Key FHE Almost as Fast as Single-Key FHE

Abtin Afshar, Rishab Goyal

Preprint

• Multi-Key FHE with Distributed Decryption: Optimal Share Size & New Trade-Offs

Abtin Afshar, Rishab Goyal

Manuscript

• Silent Distributed Cryptography for DNFs and Threshold Policies from Lattices

Abtin Afshar, Rishab Goyal, Saikumar Yadugiri

Preprint

• Encrypted RAM Delegation: Homomorphic NIZKs, Malicious MPC with Optimal Communication Complexity, and more

Abtin Afshar, Jiaqi Cheng, Rishab Goyal, Aayush Yadav, Saikumar Yadugiri

Preprint

• Verifiable Streaming Computation and Step-by-Step Zero-Knowledge

Abtin Afshar, Rishab Goyal

Preprint