In a groundbreaking experiment, a Mississippi State physicist and collaborators reveal that quarks—the building blocks of matter—don’t always play by the symmetry rules, shaking up a cornerstone of modern physics.
Key Points at a Glance
- MSU-led experiment reveals violations of expected symmetry in quark behavior
- Findings challenge assumptions used to simplify nuclear physics models
- Research offers new insight into the strong force binding atomic nuclei
- International collaboration conducted at a leading U.S. particle accelerator
- Results published in Physics Letters B, a top journal in the field
For centuries, symmetry has been a guiding principle in the way physicists interpret the universe—from the graceful spirals of galaxies to the subatomic balance of matter’s tiniest constituents. But new findings from an international research team led in part by Mississippi State University are upending this foundational concept.
In a study published in Physics Letters B, Professor Dipangkar Dutta and his collaborators detail how quarks—the elementary particles that make up protons and neutrons—sometimes violate expected patterns of symmetry. Their high-precision experiments, conducted at the U.S. Department of Energy’s Thomas Jefferson National Accelerator Facility, reveal that when quarks are struck by high-energy electrons, they don’t always behave in the even, predictable ways long assumed by physicists.
The implications are profound. Symmetry in physics isn’t just aesthetic; it’s a powerful simplification tool. Many of the equations that describe nuclear forces and particle behavior rely on symmetry-based assumptions to remain solvable. But until now, those assumptions hadn’t been rigorously tested at this level of detail.
“The assumptions we make based on symmetries greatly simplify our analyses,” Dutta explains. “But they haven’t been tested quantitatively with precision until now. Our new results show when the symmetries are valid and when they need certain corrections.”
The study zeroes in on the strong nuclear force—one of the four fundamental forces in the universe and the one responsible for binding quarks together inside protons and neutrons. By probing how quarks behave under stress, the team identified subtle asymmetries in how these particles separate and recombine—behaviors that deviate from traditional theoretical expectations.
This isn’t merely an academic nuance. These insights could refine the theoretical models used not only in particle physics, but across a range of fields where nuclear interactions matter—from energy research and materials science to advanced medical imaging and radiation therapies.
Dutta’s team included Mississippi State Ph.D. student Hem Bhatt, along with Deepak Bhetuwal and Abishek Karki, both of whom have now earned their doctorates. Postdoctoral researchers Latiful Kabir (now at Brookhaven National Lab) and Carlos Ayerbe Gayoso (now at Old Dominion University) also played vital roles. In total, physicists from 25 institutions worldwide participated in the experiment, underscoring the global scale and importance of this scientific breakthrough.
What makes this experiment stand out is its precision. Previous models relied heavily on symmetry assumptions because they made complex calculations manageable. But as technology allows scientists to make more exacting measurements, it becomes possible—and necessary—to challenge those simplifications. The experiment’s findings not only question the absolute nature of symmetry, but also provide a roadmap for when and how those rules might bend.
According to the researchers, this is just the beginning. The results set the stage for investigating even more subtle forms of symmetry and asymmetry in the universe. Understanding these fine details might one day help unlock deeper insights into the inner structure of matter—or even shed light on unsolved mysteries like the imbalance of matter and antimatter in the early universe.
By challenging the basic rules we thought governed the building blocks of nature, Dutta and his collaborators are not breaking physics—they’re refining it. Their work is a reminder that in science, even the most elegant principles must be constantly tested and reimagined.
Source: Mississippi State University
