A study reveals that the universe could be younger by two billion years

The universe seems every day younger, it seems.

New calculations suggest that the universe could be a few billion years younger than what scientists currently estimate, and even younger than two other calculations published this year that have reduced by several hundred millions of years ago the age of the cosmos.

The huge fluctuations in scientists' estimates – even this new calculation could take billions of years – reflect different approaches to the thorny problem of determining the true age of the universe.

"We have great uncertainty about how stars evolve in the galaxy," said Inh Jee, of the Max Plank Institute in Germany, lead author of the study published in the science journal Science.

Scientists estimate the age of the universe using the movement of stars to measure its speed of expansion. If the universe grows faster, it means that it has reached its current size faster and therefore needs to be relatively younger. The rate of expansion, called Hubble's constant, is one of the most important numbers of cosmology. A larger Hubble constant creates a younger universe and evolves faster.

The generally accepted age of the universe is 13.7 billion years old, based on a 70-year-old Hubble constant.

The Jee team proposed a Hubble constant of 82.4, which would give the age of the universe about 11.4 billion years.

Jee used a concept called gravitational lens, in which gravity deforms light and allows distant objects to appear closer. They rely on a special type of effect called timed lens, which uses the changing brightness of distant objects to gather information for their calculations.

But Jee's approach is that one of the few new approaches that have led to different figures in recent years, reopening a quivering astronomical debate of the 1990s that seemed to have been settled.

In 2013, a team of European scientists examined the radiation remnants of the Big Bang and said the rate of expansion was slower. Earlier this year, Astronaut Adam Riess, Nobel laureate, of the Space Telescope Science Institute, used NASA's super telescope and has 74. And another team earlier this year had 73, 3.

Jee and outside experts had big reservations for his number. It only used two gravitational lenses, all of which were available, and its margin of error is so large that it is possible that the universe may be older than expected, but not drastically younger.

Harvard astronomer Avi Loeb, who was not part of the study, said it was an interesting and unique way of calculating the rate of death. Expansion of the universe, but that large margins of error limit its effectiveness until more information can be collected.

"It's hard to be sure of your conclusions if you use a rule that you do not understand well," Loeb said in an email.

– AP