NSME faculty spotlight:

Lecturer Peng Guo discusses his research in theoretical physics

By California State University, Bakersfield

April 5^th, 2021

From a young age, Dr. Peng Guo was drawn to two things: the world of science and sunny California. Working as a physicist and lecturer while living in the Golden State is a bit of a dream come true for him, even if Bakersfield isn’t quite the same as the California that Dr. Guo loved watching on TV and in movies as a young boy in China.

Although Dr. Guo admits the chance to live in the state was a big draw of taking a job at California State University, Bakersfield, he soon realized the important role the university and its School of Natural Sciences, Mathematics, and Engineering played in the community.

“What most attracted me originally is probably the fame of the sunny state of California,” Dr. Guo said. “Now, my feeling is that there is a clear, urgent demand in Kern County for good science and physics teachers who can provide high quality training to local students to meet the needs of a STEM workforce. I am honored to be part of the community and be able to help to the growth of the Bakersfield area.”

Dr. Guo came to the United States from his rural hometown in northwestern China in 2004 to attend graduate school at Indiana University Bloomington, where he later earned his PhD in theoretical nuclear/hadron physics. Prior to joining NSME’s Department of Physics and Engineering in the fall of 2015, he worked as a postdoctoral research fellow at his alma mater in Indiana and Thomas Jefferson National Lab in Newport News, Virginia from 2009 to 2015.

“I have had great interest and curiosity in science in general since I was still a little kid,” Dr. Guo said. “As a teenager, I read several fascinating and passionate biographical stories about physicists who were involved in the Chinese nuclear program in the ’60s and ‘70s. I think perhaps that was really the defining moment that pulled me toward deciding to study physics.”

Dr. Guo’s research focuses on the investigation of the smallest detectable particles, such as protons and neutrons. The primary questions he seeks to understand are what they are made of and how they behave and interact with each other.

“Our current understanding to these two inquiries is explained by a theory called quantum chromodynamics, which suggest that the subatomic particles such as proton and neutron are made of even smaller subjects, called quarks and gluons,” he said. “The behavior of subatomic particles is, in fact, the reflection of their internal components. Although quantum chromodynamics is widely believed a correct theory in general, there are many unanswered questions and difficulties regarding the theory itself and how to use the theory to make reliable predictions.”

Although perhaps a bit difficult for a layperson to understand, Dr. Guo’s research has plenty of real-world application, most notably in nuclear energy. Beyond that, it can be essential in any number of other scientific research topics, Dr. Guo explained.

“Scientifically, studying the most fundamental particle interaction is the foundation of all other physical science,” he said. “Loosely speaking, fundamental particle science is like the foundation of a building: all other physics fields in principle are built upon it.”

In terms of technology, Dr. Guo continued, particle physics-related knowledge has been used in proton therapy, medical isotopes used in PET imaging, and touchscreen technology.

While laboratory restrictions brought on by COVID-19 have slowed down research for many scientists, Dr. Guo has been fortunate to continue his own work without issue.

“I have been lucky; as a theoretical physicist, all I need are papers, books, access to scientific journals, access to good computers, and a quiet place to think and work on computation,” he said. “COVID in fact doesn't affect me very much in my work habits.”

In the last year, Dr. Guo has been working with a student named Christopher Wisehart. Last summer, Wisehart was supposed to attend a research program at CERN (European Organization for Nuclear Research), but it was postponed because of COVID. Not wanting Wisehart to waste his summer, Dr. Guo brought him in to work on quantum simulation-related projects. The two have been able to work remotely and safely from home.

“Luckily for me and my student, we are doing either theoretical or computer simulation-related research work, so all we need are simply a quiet workplace and access to good computers,” Dr. Guo said. “Fortunately for me, I have received strong support from the physics department and also colleagues from the computer sciences department, so I have a decent desktop sitting in my office which I can use remotely to do some simple numerical computation tasks.”