Physicists just found a tiny flaw in time itself

Quantum mechanics is famous for its strange and often counterintuitive ideas. At very small scales, particles do not behave like everyday objects. Instead, they can exist in multiple states at once, a concept known as superposition. Physicists describe this behavior using a mathematical object called a wavefunction. Yet this picture clashes with what we observe in daily life, where objects occupy one definite place or state at a time. To resolve this, scientists usually propose that when a quantum system is measured or interacts with an observer, its wavefunction collapses into a single outcome.

Now, with support from the Foundational Questions Institute, FQxI, an international group of physicists has taken a closer look at alternative explanations known as quantum collapse models. Their findings suggest these ideas could have surprising consequences for how time itself behaves, including tiny limits on how precisely it can be measured. The research, published in Physical Review Research, also offers a possible way to test these models against standard quantum theory.

"What we did was to take seriously the idea that collapse models may be linked to gravity," says Nicola Bortolotti, a PhD student at the Enrico Fermi Museum and Research Centre (CREF) in Rome, Italy, who led the study. "And then we asked a very concrete question: What does this imply for time itself?"