by Clarence Oxford
Los Angeles CA (SPX) May 03, 2024
Einstein's theory of general relativity describes gravity as a result of space and time curving. This theory accounts for the Earth's gravity, which anchors us and causes objects to fall.
In contrast, high-energy physics investigates subatomic particles that follow the principles of quantum mechanics, notable for their random fluctuations and the inherent uncertainty in particle positions and energies.
For years, efforts have been underway to merge these two scientific realms into a singular quantum explanation of gravity. This pursuit aims to integrate general relativity's curvature with the randomness of quantum mechanics.
Researchers from the University of Texas at Arlington have conducted a significant study, as published in Nature Physics, examining this theoretical overlap using ultra-high energy neutrino observations from the IceCube Observatory, situated deep within the Antarctic ice.
"The challenge of unifying quantum mechanics with the theory of gravitation remains one of the most pressing unsolved problems in physics," said Benjamin Jones, associate professor of physics. "If the gravitational field behaves in a similar way to the other fields in nature, its curvature should exhibit random quantum fluctuations."
Jones, along with UTA graduate students Akshima Negi and Grant Parker, collaborated with over 300 scientists globally as part of the IceCube Collaboration. They installed numerous sensors across a square kilometer in Antarctica to monitor neutrinos-neutral, massless particles-to detect potential quantum fluctuations in spacetime indicative of quantum gravity.
"We searched for those fluctuations by studying the flavors of neutrinos detected by the IceCube Observatory," said Negi. "Our work resulted in a measurement that was far more sensitive than previous ones (over a million times more, for some of the models), but it did not find evidence of the expected quantum gravitational effects."
This lack of evidence for quantum geometry in spacetime underscores the mystery at the quantum and general relativity interface.
"This analysis represents the final chapter in UTA's nearly decade-long contribution to the IceCube Observatory," said Jones. "My group is now pursuing new experiments that aim to understand the origin and value of the neutrinos mass using atomic, molecular and optical physics techniques."
Research Report:The IceCube Collaboration. Search for decoherence from quantum gravity with atmospheric neutrinos
Related Links
IceCube Neutrino Observatory
University of Texas at Arlington
The Physics of Time and Space