Research Interests: Quantum Information Science. I have worked on several topics in theoretical quantum information science: query complexity, computational complexity, communication complexity, universality, classical simulations, quantum channels, and quantum cryptography. My current projects include quantum cryptography (see my tutorial talk "Untrusted Quantum Devices"), quantum algorithms, and quantum error-correction. I am also interested in learning and exploring "post-quantum" cryptography, or classical cryptography secure against a quantum adversary. Most, if not all, widely used public key cryptography systems (such as RSA) are not secure under quantum attack. Thus as quantum computing becomes a reality, the subject of post-quantum cryptography will be more and more important.