It’s a question that has vexed scientists for ages: How old is our universe?
The question is simple enough, but as the years go by it’s become apparent that settling on the answer isn’t quite so easy. Even today, the matter remains open to discussion as new research could at any moment upend our previous cosmic conception for the age of the billions of galaxies that comprise our universe.
That’s what happened last week when a new study was released challenging the long-held notion that our universe is nearly 13.8 billion years old. If the findings of this latest research prove accurate, the Big Bang may have taken place 26.7 billion years ago, making the actual age of the universe nearly twice as old as we thought.
‘Internet apocalypse’:How NASA’s solar-storm studies could help save the web
How the ‘impossible early galaxy problem’ undermined our understanding of the universe’s age
For years, astronomers and physicists have primarily calculated the age of the cosmos by measuring the time elapsed since the Big Bang and studying the oldest stars.
But the study published July 7 in the journal “Monthly Notices of the Royal Astronomical Society” seems to confirm that previous estimates were widely off. What’s referred to in the new study as the “impossible early galaxy problem” has long baffled scientists who struggle to reconcile why some galaxies thought to have come into existence long after the Big Bang appear to in fact be much older that the universe’s estimated age.
Observed through NASAS’s James Webb Telescope, galaxies and stars like the Methuselah appear to have a a level of maturity and mass typically associated with billions of years of cosmic evolution. It’s a notable observation considering the widely-held belief that they came to existence hundreds of millions of years after the Big Bang.
But now, Rajendra Gupta, a theoretical physicist at the University of Ottawa who authored the study, believes he can explain the conundrum that has long puzzled scientists about these ancient galaxies.
“Our newly-devised model stretches the galaxy formation time by a several billion years,” Gupta wrote.
How did the study determine the universe could be 26.7 billion years old?
Calculating the time that has passed since the Big Bang is not the only method scientists have used to estimate the age of the universe.
The redshift of light — literally, light from distant galaxies stretched and shifted toward the red part of the spectrum — is what has long helped to inform physicists’ estimates of the universe’s age. In simple terms, the thought has been that the redshift indicated the distance of stars and galaxies, and hence, the faster they are moving away from Earth.
By estimating the rate at which the stars are moving away, scientists can calculate how fast space is expanding into an infinitely-growing universe.
But the so-called “tired light theory” that originated in 1929 with Swiss astronomer Fritz Zwicky offered an alternative explanation: Perhaps the redshift we see isn’t due to galaxies moving away from us. Instead, Zwicky’s hypothesis was that it might be because light loses its energy and shine after traveling a long distance.
Alien technology?Harvard professor finds fragments that could be of otherworldly origin
Gupta proposes that if we allow Zwicky’s theory to coexist with the idea of an expanding universe, we can reinterpret the redshift as a hybrid of both of these phenomena and thus arrive at an even more accurate age estimate of the universe.
And Gupta goes even further in the study, introducing the fundamental physics idea from English theoretical physicist Paul Dirac that coupling constants govern the interactions between particles.
What does that mean? If these constants evolve, then the time it takes for the early galaxies observed in the Webb telescope to form extends from a few hundred million years to several billion years.
Better put, it would offer an explanation for the advanced level of development and mass observed in the previously puzzling early galaxies.
Eric Lagatta covers breaking and trending news for USA TODAY. Reach him at elagatta@gannett.com and follow him on Twitter @EricLagatta.
