Avengers: Infinity War
, before Thanos snaps his finger, Wanda tries to stop him by killing Vision herself before he gets the Mind Stone, but Thanos has the Time Stone allowing him to reverse the passage of time as he tells a heartbroken Wanda: “This is no time to die. Now is no time at all.” It would appear that quantum physics agrees.
A recent study proposes that time might not be a fundamental aspect of the universe but rather an illusion stemming from quantum entanglement.This new perspective aims to address the inconsistencies between our best theories of the universe, which have hindered the development of a unified “theory of everything.”
Researchers have suggested that by considering time as a result of quantum entanglement, the mysterious connection between two distant particles, they might solve this long-standing problem. The study, published on May 10 in the journal Physical Review A, explores this idea.
“We have found a way to introduce time that is consistent with both classical and quantum laws, manifesting from entanglement,” said Alessandro Coppo, a physicist at the National Research Council of Italy. “The correlation between the clock and the system leads to the emergence of time, a fundamental aspect of our lives.”
In quantum mechanics, time is seen as a fixed, unidirectional flow from the past to the present, external to the quantum systems it measures. This contrasts with Einstein’s theory of general relativity, where time is intertwined with space and can be warped by gravity or high speeds. This discrepancy has left physicists without a coherent theory of everything.
To tackle this issue, the researchers revisited the Page and Wootters mechanism, proposed in 1983. This theory suggests that time emerges for an object through its quantum entanglement with another object acting as a clock. In an unentangled system, time doesn’t exist, and the universe appears static.
By applying this mechanism to two entangled but noninteracting theoretical quantum states — a vibrating harmonic oscillator and a set of tiny magnets acting as a clock — the researchers found that their system could be described by the Schrödinger equation. Instead of time, the equation ran according to the states of the tiny magnets.
The team took a novel step by repeating their calculations with the magnet clock and the harmonic oscillator as larger objects. Their equations simplified into those for classical physics, indicating that time’s flow results from entanglement even on a macroscopic scale.
“We believe starting from quantum physics to understand classical physics is the correct approach,” Coppo said.
Other physicists have expressed cautious interest. Vlatko Vedral, a quantum information science professor at the University of Oxford, noted that while the idea is mathematically consistent, it has yet to produce testable predictions. Adam Frank, a theoretical physicist at the University of Rochester, suggested that understanding time might require considering its role in life and the world as we perceive it. Building theories of time from quantum mechanics could be promising, provided they can be experimentally validated.
