A new study suggests that time may not be a fundamental element of the universe, but rather an illusion created by quantum entanglement.
time The contradiction between our best theories of the universe is a thorny problem for physicists, as its inconsistent behavior contributes to a dead end that prevents researchers from finding a “theory of everything,” or a framework to explain all the physics in the universe.
But in the new study, researchers suggest they may have found a clue to solve this problem: by making time a function of quantum entanglementa strange connection between two distant particles. The team published their results on May 10 in the journal Physical Review A.
“There is a way to introduce time that is compatible with both classical and quantum laws, and it is a manifestation of entanglement,” first author Alessandro Cobo“The connection between the clock and the system creates the appearance of time, which is a fundamental element of our lives,” the physicist at Italy’s National Research Council told Live Science.
It’s about time.
in Quantum mechanicsAccording to our best theories of the microscopic world, time is a constant phenomenon—a relentless flow in one direction from past to present. Time remains external to the strange, ever-changing quantum systems it measures, and can only be seen by observing changes in external entities, such as the hands of a clock.
Related: Atoms are squeezed closer together than ever before, revealing seemingly impossible quantum effects.
However, according to Einstein’s theory, General relativity Time—which describes larger objects, like our own bodies, stars, and galaxies—is intertwined with space, and can be warped and stretched at high speeds or in the presence of gravity. This leaves our two best theories of reality in a fundamental impasse. Without a solution to this conundrum, a coherent theory of everything remains elusive.
“There seems to be a serious contradiction in quantum theory, and that’s what we call the time problem,” Kubo says.
To solve this problem, researchers turned to a theory called the Bigwaters mechanism. First proposed in 1983, this theory suggests that time is created for a single object by its motion. quantum entanglement On the other hand, for an unentangled system, there is no time, and the system perceives the universe as frozen and unchanging.
By applying the Bigwaters mechanism to two theoretical entangled but non-interacting quantum states—one a vibrating harmonic oscillator and the other a collection of tiny magnets acting like a clock—the physicists found that their system could be described exactly by Schrodinger equationwhich predicts the behavior of quantum objects. However, instead of time, their version of the famous equation operated according to the states of tiny magnets acting as a clock.
This insight isn’t new, but the team’s next step was. They repeated their calculations twice, first assuming that the magnet clock and then the harmonic oscillator were large (larger) objects. They then simplified their equations to those of classical physics, suggesting that the flow of time is a result of entanglement even for objects on large scales.
“We strongly believe that the right and logical direction is to start from quantum physics and understand how to get to classical physics, not the other way around,” Kubo said.
Other physicists were more cautious. While they found the Bigwaters mechanism to be a fascinating clue about the quantum origins of time, they said it had not yet yielded anything that could be tested.
“Yes, it makes mathematical sense to think of cosmic time as the entanglement of quantum fields and quantum states of three-dimensional space,” Flatco Federal“However, no one knows whether anything new or fruitful will come out of this picture — such as modifications to quantum physics and general relativity, and corresponding experimental tests,” Professor John Jordan, a professor of quantum information science at the University of Oxford who was not involved in the work, told Live Science.
Despite these doubts, building theories of time from scratch from quantum mechanics may nevertheless be a promising starting point—as long as they can be shaped to fit experiments.
“Maybe there’s something about entanglement that plays a role.” Adam Frank“Perhaps the only way to understand time is not from a divine perspective, but from within, from the perspective of asking what life is that manifests itself in this manifestation of the world,” a theoretical physicist at the University of Rochester in New York, who was not involved in the study, told Live Science.