A recent study proposes that our universe might be twice as old as previously estimated, challenging the prevailing cosmological framework and shedding new light on the perplexing “impossible early galaxy problem.”
The findings have been documented in the Monthly Notices of the Royal Astronomical Society.
Rajendra Gupta, an adjunct professor of physics in the Faculty of Science at the University of Ottawa and the author of the study, explains, “Our newly formulated model extends the timeline for galaxy formation by several billion years, suggesting that the universe is approximately 26.7 billion years old, significantly older than the previously accepted estimate of 13.7 billion years.”
Traditionally, astronomers and physicists have determined the age of the universe by calculating the time since the occurrence of the Big Bang and analyzing the oldest stars, primarily based on the redshift of light originating from distant galaxies. In 2021, advancements in technology and innovative methodologies led to the estimation of the universe’s age at 13.797 billion years, following the Lambda-CDM concordance model.
Nevertheless, the presence of stars such as Methuselah, seemingly older than the universe’s estimated age, and the revelation of early galaxies in an advanced developmental stage, as observed by the James Webb Space Telescope, have confounded many scientists. These early galaxies, emerging just 300 million years post-Big Bang, exhibit characteristics typically associated with billions of years of cosmic evolution. Additionally, their relatively diminutive size adds another layer of complexity to the puzzle.
Zwicky’s theory of tired light posits that the redshift of light from distant galaxies results from the gradual dissipation of energy by photons across vast cosmic distances. However, previous observations seemed to contradict this theory. Nevertheless, Gupta proposes that by reconciling this theory with the expanding universe concept, it becomes feasible to interpret the redshift as a combined phenomenon, rather than solely attributable to expansion.
Furthermore, Gupta introduces the concept of evolving “coupling constants,” initially postulated by Paul Dirac. These constants, which govern particle interactions, may have experienced variations over time according to Dirac’s hypothesis. Allowing for their evolution extends the timeframe for the formation of early galaxies observed by the Webb telescope at high redshifts from a few hundred million years to several billion years. This offers a more plausible explanation for the advanced developmental stage and substantial mass observed in these ancient galaxies.
Moreover, Gupta suggests revising the conventional interpretation of the “cosmological constant,” representing dark energy responsible for the universe’s accelerating expansion. Instead, he proposes a constant that accommodates the evolution of coupling constants. This adjustment to the cosmological model aids in addressing the puzzle of small galaxy sizes observed in the early universe, facilitating more precise observations.