# Math junior flips for ‘bit flips’

Paul Ziquan Yang is using mathematical techniques to eliminate errors in computer hardware.

Over the summer, the rising junior math major worked with Robert Calderbank, Charles S. Sydnor professor of computer science, as part of the PRUV Fellowship program, a six-week mentorship sponsored by the Department of Mathematics. Yang now plans to continue to work with Calderbank in the fall and may turn the project into a senior thesis.

“Professor Calderbank has been a great source of encouragement and inspiration,” Yang said. “I used to be an engineering major at Pratt, and he was also the one who helped me make my mind to transfer to Trinity and focus on math because that suits me better. I have learned much more from him than just math.”

Yang, from Beijing, China, is studying coding theory, and focusing on how to repair incorrectly stored data. In a computer’s hardware, all information is stored in the form of bits—binary values of zero or one.

Within computers, something called a bit flip occasionally occurs where a value of one is replaced with zero or vice versa. In small amounts, these errors are harmless, but when they accumulate they can actually prevent machines from running correctly.

“Our aim is to add redundant information to a fixed list of binary bits so that we can detect the error and possibly correct it,” Yang said. “It’s sort of like cryptography but the aim is different.”

Cryptography is the study and use of mathematical techniques to secure communications and data in the presence of third parties. While cryptography is used to enforce the security of information, Yang employs similar mathematical methods to fix binary coding errors.

Yang noted that he is very excited about his research. “My favorite part is to see the interaction of various branches of math, and how research can connect these branches, even if they seem unrelated at first.”

His classes have provided him with both a theoretical and applied background for his research. His coursework has also trained him in the ways of thinking necessary to develop research questions.

Outside of his classes and research, Yang enjoys spending time with his friends and reading. He said he has also started taking tennis lessons for the first time, and is enjoying the sport more than he expected.

Yang said his long-term plan is eventually to become a professor. After graduation, he is planning on getting a Ph.D. in math, but is still unsure of what he would like to focus on in the field

“The research done at an undergraduate level doesn’t necessarily determine your subject at a graduate level,” Yang said. “I’ll see what interests me more over the next two years of courses.”