Tick-tock, tick-tock. The reassuring sound of the hands marking the seconds, the minutes, the hours. But what if I told you that that clock doesn't measure anything real? That the time, as we perceive it, could be just an illusion generated by the bizarre laws of quantum mechanics? This is the bold hypothesis advanced by a team of Italian physicists from the CNR, who in a recent article propose to explain the nature of time through the Page-Wootters mechanism. Now I'll try (but I may not succeed) to explain it better.
A suggestive idea: time emerges from entanglement
According to the theory illustrated by Alessandro Coppo, Alessandro Cuccoli e Paola Verrucchi, time would not be an intrinsic property of the universe, but would emerge fromentanglement between quantum systems, such as a clock and the evolving system it measures. In other words, time would exist only as a result of correlations between quantum states, and not as a fundamental dimension of physical reality.
In simple words?
Imagine having a big party with lots of friends. Every time someone tells a joke, everyone laughs together, creating an atmosphere of joy. In this scenario, the party represents the universe and the laughter is time.
According to the theory of Coppo, Cuccoli, and Verrucchi, time is not like a clock that ticks independently; rather, it emerges from the connection between people laughing together. If no one laughs, there is no perceived “time” at the party. Thus, just as laughter creates a sense of time at the party, quantum entanglement creates time through interactions between quantum systems.
To test this hypothesis, the researchers simulated two non-interacting but “entangled” quantum systems: a vibrating harmonic oscillator and a set of small magnets that act as a clock. The results showed that the oscillator’s evolution was dictated not by an external time parameter, but by the quantum state of the clock. An observation that supports the idea of time as an emergent property, rather than an independent background.
Towards a solution to the “time problem”
The Italian team's proposal could offer a way out of one of the greatest puzzles of modern physics: the incompatibility between the description of time in quantum mechanics and in general relativity. While the first treats time as an external and immutable parameter, the second considers it a dimension intertwined with space, influenced by mass and movement.
This discrepancy, known as “time problem“, has for decades been an obstacle on the way to a unified theory of the universe. But if time were not a fundamental feature of reality, but rather a quantum illusion, the conflict between the two great theories of modern physics could dissolve. A fascinating idea, which opens up completely new scenarios in our understanding of nature.
From Quantum Physics to Classical Reality
But the surprises don't end there. The researchers pushed their analysis further, applying the Page-Wootters mechanism to macroscopic systems. Assuming that the magnetic clock or harmonic oscillator were classical objects, they found that the equations simplified naturally to those of classical physics.
This suggests that the flow of time as we experience it at a macroscopic level might emerge from quantum entanglement, even on larger scales. An idea that supports the view of classical physics as an approximation of quantum physics, rather than as a separate framework. And that strengthens the hypothesis of time as a product of quantum correlations, rather than as a fundamental reality.
Physics and Time: The Next Stop? Experimental Tests
Of course, as mathematically coherent and fascinating as it may be, the proposal of time as a quantum illusion remains for now only a theoretical hypothesis. To confirm or deny this idea, experimental tests will be needed to measure the effects of entanglement on the temporal evolution of real systems.
A challenge not to be underestimated, which will require the development of innovative technologies and protocols. But if the experiments prove the Italian physicists right, the implications would be enormous. Not only for our understanding of time and physical reality, but for the entire structure of modern science.
A new horizon for time and physics
In a sense, the idea of time as a quantum illusion forces us to rethink everything we thought we knew about the universe. If time is not a fundamental feature of reality, but only an approximation valid at the macroscopic level, many of the concepts on which physics is based may need a profound revision.
At the same time, this prospect opens up completely new and unexplored horizons. From the possibility of finally unifying quantum mechanics and general relativity, to the development of technologies based on temporal entanglement, the implications could be revolutionary in fields ranging from theoretical physics to quantum computing.
Time and Physics, Questions for You
But perhaps the most fascinating aspect of this idea is the way it forces us to rethink our very perception of reality. If time is indeed an illusion, what does this mean for our subjective experience? How can we reconcile the sense of a flow of time with the idea that time does not exist as a fundamental reality?
These are profound questions, which touch not only physics, but philosophy, psychology, perhaps even spirituality. Questions to which, for now, we have no definitive answers, and which push us to explore with renewed enthusiasm the deepest mysteries of nature. Because, after all, this is the beauty of science: the courage to question even the most deeply rooted certainties, to always push beyond the boundaries of the known. Towards a boundless horizon of possibility and wonder.
