Hold back time, don’t climb the stairs
Climbing the stairs or to the top of a mountain really can age you,
but don’t worry you can set the clock back by taking a quick trip in the
car, a new study said Friday.
Scientists in Boulder, Colorado say they have proved what every
schoolchild learns in the classroom about Einstein’s theory of
relativity — that time flies at altitude but paradoxically slows down
when people speed up.
Decades ago, experiments proved the basic premise of Albert
Einstein’s theory, sending an atomic clock into space on a rocket and
comparing it to one kept behind on Earth, where gravity acts to slow
down the passage of time.
But now experiments at the National Institute of Standards and
Technology (NIST) have enabled physicists to demonstrate the theory in
the smallest facets of daily life.
In the study, published Friday in Science, they showed how they
measured the effect on a scale of about one foot (33 centimeters) to
demonstrate how people age faster when standing a couple of steps higher
on the staircase.
They used a pair of highly sophisticated experimental atomic clocks,
dubbed “quantum logic clocks,” which use laser lights to measure an
electrically charged aluminium ion as it vibrates more than a million
billion times a second.
One clock keeps time within one second in about 3.7 billion years,
the study said, and the other is close behind.
The aluminum clocks can detect small relativity-based effects because
of their extreme precision, the study said. “You can think about it as
how long a tuning fork would vibrate before it loses the energy stored
in the resonating structure,” said lead author James Chin-Wen Chou.
Although the results are infinitessimally small, they showed that
climbing up steps will age you faster — adding up to about 90 billionths
of a second over a 79-year lifespan.
In one of the experiments, scientists raised one of the clocks by
elevating the laser table to a foot above the second clock. “Sure
enough, the higher clock ran at a slightly faster rate than the lower
clock, exactly as predicted,” the study said.
The NIST team also studied another feature of relativity — that time
passes more slowly when you move faster — but measured the effect at
speeds such as a car travelling about 20 miles per hour (32 kilometers),
rather than on jet aircraft.
AFP |