At a Glance
- Scientists have long struggled to unify quantum field theory and general relativity, which describe the universe at different scales but remain incompatible in extreme environments.
- A new theory from Aalto University proposes using gauge theory to describe gravity, aligning it with the other three fundamental forces in the Standard Model.
- This approach could help explain cosmic phenomena like black holes and the Big Bang by enabling gravitational calculations at tiny scales.
- The theory is still under development and must be tested for mathematical consistency, particularly with complex higher-order calculations.
- Researchers are optimistic that this framework could bring physics closer to a unified theory, opening new paths for scientific discovery.
For decades, scientists have been working to merge two fundamental theories of physics: quantum field theory and general relativity. These theories describe different aspects of the universe—quantum field theory explains the behavior of tiny particles, while general relativity focuses on larger objects like planets and gravity. However, they do not fit together well. A new theory from researchers at Aalto University, whose findings were published in Reports on Progress in Physics, could provide a breakthrough, offering a way to describe gravity compatible with the other forces in the Standard Model of particle physics.
The team’s new approach uses a concept called “gauge theory,” a theory where particles interact through a field. The electromagnetic force, which is familiar to most people, is an example of a gauge field. This new theory seeks to describe gravity in a similar way, allowing it to align with the other three fundamental forces—electromagnetism, weak nuclear force, and strong nuclear force—without the incompatibilities of general relativity.
This breakthrough could change scientists’ understanding of extreme environments, like black holes or the early universe after the Big Bang, where current theories fail. The new theory might eventually solve these problems by describing gravitational interactions at tiny scales, helping to bridge the gap between the universe’s smallest particles and the biggest structures in space. The potential impact is enormous, as it could open up new avenues for understanding phenomena we cannot currently explain.
While the theory is promising, it is still in development. Researchers need to prove that it works at all levels, particularly with “higher order” terms, to ensure that calculations remain valid and don’t lead to infinite results. The team hopes to refine their work over the years, contributing to a deeper understanding of the universe’s fundamental forces. For now, their work is available for the scientific community to explore, test, and build upon.
References
- Partanen, M., & Tulkki, J. (2025). Gravity generated by four one-dimensional unitary gauge symmetries and the Standard Model. Reports on Progress in Physics, 88(5), 057802. https://doi.org/10.1088/1361-6633/adc82e
- Aalto University. (2025, May 5). New quantum theory of gravity brings long-sought ‘theory of everything’ a crucial step closer. Phys.Org; Aalto University. https://phys.org/news/2025-05-quantum-theory-gravity-sought-crucial.html
