291 citations · 377 across the 15 of their papers we have counts for
5 papers · 2 filters
Space-Efficient Error Reduction for Unitary Quantum Computations
Bill Fefferman, Hirotada Kobayashi, Cedric Yen-Yu Lin +2
This paper develops general space-efficient methods for error reduction for unitary quantum computation. Consider a polynomial-time quantum computation with completeness and so…
A Complete Characterization of Unitary Quantum Space
Bill Fefferman, Cedric Yen-Yu Lin
Motivated by understanding the power of quantum computation with restricted number of qubits, we give two complete characterizations of unitary quantum space bounded computation. F…
On Quantum Obfuscation
Gorjan Alagic, Bill Fefferman
Encryption of data is fundamental to secure communication in the modern world. Beyond encryption of data lies obfuscation, i.e., encryption of functionality. It is well-known that…
Computational Security of Quantum Encryption
Gorjan Alagic, Anne Broadbent, Bill Fefferman +3
Quantum-mechanical devices have the potential to transform cryptography. Most research in this area has focused either on the information-theoretic advantages of quantum protocols…
Quantum Merlin Arthur with Exponentially Small Gap
Bill Fefferman, Cedric Lin
We study the complexity of QMA proof systems with inverse exponentially small promise gap. We show that this class can be exactly characterized by PSPACE, the class of problems sol…