CSE’s Qipeng Liu Is Redefining Cryptography with Quantum Computing

Jan 16, 2024
New CSE Assistant Professor Qipeng Liu

Cryptography is as ancient as hieroglyphics. Forever evolving from these rudimentary origins, the process of hiding or coding private information has grown increasingly complex – think World War II ciphers, early computers, and today’s quantum computers. This latest frontier, quantum computing, is what brought Qipeng Liu to UC San Diego as a new assistant professor in the Department of Computer Science and Engineering.

“One of my research interests is to redefine cryptography in the age of quantum computing. Cryptography stands as one of the pivotal technologies in contemporary society, silently safeguarding our daily activities,” said Liu.

Liu is referring to the online activities that comprise day-to-day life in our modern, hyper-connected world. Whether you’re conducting a financial transaction, sending a personal email or text message, or simply logging into your social media account, cryptography protocols protect your personal information from anyone other than the intended parties.

According to Liu, the advent of quantum computers could destroy current cryptographic protocols. These protocols rely on calculations that are computationally intractable on classical computers. Now they’re insufficient.

“We need to rethink cryptography. Almost all hard problems used in building cryptography are no longer difficult with a quantum computer,” explained Liu.

While Liu has a broad interest in theoretical computer science, his research focuses on developing novel cryptographic solutions that utilize the power of quantum information and quantum computers. One avenue of his research could establish the theoretical foundations for creating unclonable software, potentially enhancing classical approaches to software copy-protection.

Liu arrived in San Diego last summer and says he’s done some of his best problem-solving while walking along the beach. With Fall term underway, he is eager to work collaboratively with other professors and students in computer science to pursue and advance knowledge in the field.

“UC San Diego offers one of the best computer science departments in the United States, and its theory group has world-class professors working in all areas of CS theory,” said Liu. “My research passions revolve around the convergence of theoretical computer science, cryptography, and quantum computing; the CSE department is home to leading experts in all these domains.”

Prior to joining UC San Diego, Liu was a Simons Quantum Postdoctoral Fellow at UC Berkeley. He earned his PhD in computer science at Princeton University, where he was awarded the Francis Robbins Upton Fellowship, the highest honor for incoming graduate students. Liu was also the recipient of the China National Scholarship while an undergrad at Tsinghua University in Beijing.

--By Kimberley Clementi