Suffolk Reporter

Scientists at the U.S. Department of Energy’s Brookhaven National Laboratory, along with collaborators including Dmitri Kharzeev from Stony Brook University, have developed a new method to examine protons using data from high-energy particle collisions. This approach employs quantum information science to explore how particle tracks from electron-proton collisions are influenced by quantum entanglement within the proton.

The study reveals that quarks and gluons, fundamental components of a proton's structure, experience quantum entanglement. This phenomenon was described by Albert Einstein as "spooky action at a distance," indicating that particles can be aware of each other's state even when separated by large distances. In protons, entanglement occurs over extremely short distances—less than one quadrillionth of a meter—and affects the entire group of quarks and gluons within a proton.

Published in the journal Reports on Progress in Physics, the team's paper summarizes six years of research. It details how entanglement influences the distribution of stable particles formed after quarks and gluons released in collisions merge into new composite particles.

This perspective on entanglement among quarks and gluons adds complexity to our understanding of protons' internal structure and may provide insights into other scientific areas where entanglement is significant.

The researchers utilized quantum information science's language and equations to predict how entanglement impacts particles from electron-proton collisions. Developed by Kharzeev in 2017, this approach was tested against experimental data in their latest paper.

"For a maximally entangled state of quarks and gluons, there is a simple relation that allows us to predict the entropy of particles produced in a high energy collision," said Kharzeev. "In our paper, we tested this relation using experimental data."

Zhoudunming (Kong) Tu, another co-author who joined Brookhaven Lab in 2018, noted: “For decades, we’ve had a traditional view of the proton as a collection of quarks and gluons... Now, with evidence that quarks and gluons are entangled, this picture has changed.”

The full story is available on the BNL website.