Obfuscation is a Wheelbarrow: How to Build Long-Sought Cryptography Using Complexity Theory

Over the past 50 years, cryptographers have constructed a number of surprising and important primitives like public-key encryption, which allows strangers to communicate privately even if eavesdroppers hear everything they say. However, there are still many basic primitives that cryptographers believe should exist but have not yet been able to construct.

In this talk, I’ll describe a powerful new complexity-theoretic approach to constructing cryptographic primitives. This approach has already led to multiple long-sought constructions, including public-key encryption with “optimal” security. A key idea is to use “circuit obfuscators” (I’ll explain what these are) to transfer statements from complexity theory to cryptography.

No background in cryptography assumed. Based on joint work with Alex Lombardi (https://eprint.iacr.org/2025/1087).