A small error in time has been detected by physicists, and it is tied to clocks that lack the precision needed to spot it. The research, published in Physical Review Research, points to time carrying an inherent, built-in uncertainty that is much tinier than any measurement we can make right now.
Nicola Bortolotti, a PhD student at the Enrico Fermi Museum and Research Centre (CREF) in Rome, Italy, leads the team behind the work. Backed by the Foundational Questions Institute, FQxI, he and his colleagues examined quantum collapse models, which diverge from standard quantum theory by permitting wavefunctions to collapse on their own. No measuring device or observer is required for this spontaneous collapse to happen.
The Clock Problem
Quantum mechanics typically regards time as a fixed stage set apart from the quantum realm, with events playing out against a steady backdrop. Collapse models take a distinct approach, suggesting that gravity may compel quantum systems to resolve into clear states. These models further suggest that such resolution could produce a ripple that moves through time.
Two models were examined by the team. One is the Diósi-Penrose approach, named after FQxI members Lajos Diósi and Sir Roger Penrose. That model has long proposed that gravity forces quantum systems to collapse. The other is Continuous Spontaneous Localization, which the team studied for the first time alongside gravitational fluctuations in spacetime.
The numbers point toward a striking conclusion: if the models of collapse hold true, then time carries within it an extremely tiny amount of inherent doubt. It is possible that there exists a basic boundary on how accurately time can ever be gauged.
Why It Matters
This change is so slight that even the most exact atomic clocks running now, or those anticipated for the near future, lack the precision needed to detect it. The error margin sits far below what our current measuring instruments can register.
That means the finding has no practical consequences for everyday timekeeping. “Once you do the calculation, the answer is clear and surprisingly reassuring,” said Bortolotti.
These models make predictions that can be tested through measurement, and those predictions diverge from what standard quantum mechanics would suggest. Extremely precise experiments may ultimately help decide whether these ideas actually describe something real in nature.
The Gravity Connection
One of the largest unanswered questions in modern physics is the reconciliation of quantum mechanics with gravity. This work addresses that problem. Quantum mechanics offers an extremely successful account of atoms, particles, and other tiny systems. General relativity, by contrast, handles gravity and the behavior of space and time on far larger scales — planets, stars, galaxies, and even the universe itself.
In the realms where they are put to use, both theories match experimental results with great precision. Yet their treatment of time could not be more distinct from one another.
“In standard quantum mechanics, time is treated as an external, classical parameter that is not affected by the quantum system being studied,” explains Catalina Curceanu, a member of FQxI and research director at the Laboratori Nazionali di Frascati of the National Institute for Nuclear Physics (INFN-LNF) in Frascati, Italy.
General relativity offers an entirely distinct perspective. It treats space and time not as separate entities, but as a single flexible framework known as spacetime, which warps and shifts under the influence of mass and energy. The gap between these two approaches has fueled decades of effort aimed at finding a more fundamental theory capable of reconciling quantum mechanics with gravity.
New findings point toward hints that collapse models could reveal how quantum physics, gravity, and time connect. The study involved Kristian Piscicchia from CREF and INFN-LNF, Lajos Diósi of the Wigner Research Center for Physics and Eötvös Loránd University in Budapest, Hungary, and Simone Manti of INFN-LNF.
What This Means for Science
That the most basic things we take for granted — such as the passage of time — may carry subtle, hidden structure is the lesson here. The effect is so slight that it cannot be detected by today’s instruments. That it can be computed at all, however, matters greatly.
This demonstrates that collapse models are more than mere theoretical conjecture; they produce testable predictions that could be examined in a laboratory setting. Such findings are precisely what advances scientific knowledge.
The project highlights the importance of funding studies into strange questions at the base of physics.
Hard Numbers
- Study: Published in Physical Review Research
- Team: Led by Nicola Bortolotti, PhD student at CREF, Rome
- Support: Foundational Questions Institute, FQxI
- Models studied: Diósi-Penrose model, Continuous Spontaneous Localization
- Uncertainty scale: Many orders of magnitude below anything we can currently measure
The paper’s honest reaction to this story is that the finding is a reminder of how much we still don’t know about the most basic building blocks of reality. A team of physicists has shown that even time — the thing we measure most accurately — may carry a fundamental, tiny uncertainty. The effect is so small it is unmeasurable today, but the idea it supports is big: a link between the most fundamental forces in the universe and the very fabric of time.