Using Einstein's theory that the passage of time depends on the speed of movement, researchers have developed a new theory based on this dynamic understanding of time. Photo by Security
Oct. 23 (UPI) -- Not even the most precise atomic clocks are immune to the quantum phenomenon known as superposition, according to a new theory developed by a team of physicists from Dartmouth College, Saint Anselm College and Santa Clara University.
Superposition describes the ability of an atom to simultaneously exist in multiple states. In a new study, published Friday in the journal Nature, scientists theorize that superposition leads a correction in atomic clocks -- an effect the study's authors call "quantum time dilation."
The new theory builds on Albert Einstein's theory of relativity, but offers a novel prediction about the nature of time.
"Whenever we have developed better clocks, we've learned something new about the world," lead researcher Alexander Smith said in a news release.
"Quantum time dilation is a consequence of both quantum mechanics and Einstein's relativity, and thus offers a new possibility to test fundamental physics at their intersection," said Smith, an assistant professor of physics at Saint Anselm College and adjunct assistant professor at Dartmouth College.
At the beginning of the 20th century, Einstein became one of the first to challenge Isaac Newton's absolute notion of time. Einstein showed that the experience of time depends on speed. The faster a clock moves through space, Einstein theorized, the slower it ticks.
For the latest paper, scientists reimagined Einstein's ideas though the gaze of quantum physics.
According to quantum mechanics, atomic clocks are simultaneously moving at two different speeds -- a quantum "superposition" of speeds. By accounting for this phenomenon, researchers were able to develop a probabilistic theory of timekeeping, which revealed the effect of quantum time dilation.
"Physicists have sought to accommodate the dynamical nature of time in quantum theory for decades," said study co-author Mehdi Ahmadi, a lecturer at Santa Clara University. "In our work, we predict corrections to relativistic time dilation which stem from the fact that the clocks used to measure this effect are quantum mechanical in nature."
Atomic clocks rely on the lifetime of an excited atom to tell time. The lifetime is the amount time an atom remains in an excited state or resonates at a specific frequency after being excited or petered in a specific way.
If superposition causes an atom to exist in different states, or move at two different speeds, at the same time, than the atom's lifetime will either increase or decrease compared to an atom traveling at a definite speed.
Scientists suggest this effect would be infinitesimally small, too small to comprehend on human scales. However, researchers estimate the quantum time dilation could be measured by the world's most precise atomic clocks. If so, the effect could be used to test a variety of theories related to quantum mechanics.