The Standard Model explains three fundamental forces—electromagnetism, the weak force, and the strong force—but gravity remains separate. Scientists struggle to unify gravity with the Standard Model because its governing theory, general relativity, follows mathematical rules different from those of quantum physics.
While quantum theories rely on compact, simple symmetries, general relativity involves complex, infinite spacetime structures, making integration difficult.
A major breakthrough in quantum gravity has been achieved at Aalto University, where researchers have developed a new theory that aligns gravity with the Standard Model of particle physics.
This advancement could deepen our understanding of the universe’s origins and pave the way for future discoveries. While theoretical physics may seem distant from everyday technology, its impact is profound—GPS, for instance, relies on Einstein’s theory of gravity to function accurately.
Is gravity truly a quantum force?
If scientists develop a full quantum field theory of gravity, it could help solve mysteries like black holes and the Big Bang.
The Theory of Everything aims to unify all fundamental forces, but some major questions remain unanswered, such as why the universe has more matter than antimatter.
Researchers focused on gauge theory to make gravity fit with quantum physics, which describes forces through fields. Since the Standard Model already works this way, the idea is to create a gravity gauge theory with similar symmetries rather than relying on general relativity’s very different spacetime rules.
Without a unified theory, physicists cannot bridge the gap between quantum field theory and general relativity. Quantum physics explains particles’ tiny, probabilistic interactions, while general relativity describes large-scale gravitational forces. Both theories have been tested with incredible accuracy but remain fundamentally incompatible.
Since gravity is extremely weak at quantum scales, scientists need even greater precision to detect true quantum gravity effects beyond the classical framework of general relativity.
Scientists may have discovered the fifth force of nature
A quantum theory of gravity is essential for exploring extreme environments where gravity and high-energy physics interact, such as black holes and the early universe after the Big Bang—places where current theories break down.
Driven by a deep curiosity about fundamental physics, he uncovered a new symmetry-based approach to gravity and collaborated with Tulkki to refine it. This breakthrough can potentially revolutionize scientific understanding, like the discovery of gravity, eventually leading to technologies like GPS.
While the theory looks promising, it isn’t entirely proven yet. The researchers use a process called renormalization, which helps handle infinities in calculations. So far, they’ve shown it works for simpler cases, but they must confirm it works throughout. If it fails at higher levels, the results could become meaningless. Despite the challenge, they’re optimistic that with time and effort, they’ll find answers within a few years.
Journal Reference:
- Mikko Partanen and Jukka Tulkki. Gravity is generated by four one-dimensional unitary gauge symmetries and the Standard Model. Reports on Progress in Physics. DOI 10.1088/1361-6633/adc82e
