New Study Suggests Universe Might Be Twice as Old as Previously Thought
When the James Webb Space Telescope (JWST) first began its mission of observing distant galaxies, it provided astronomers with an unprecedented view of the cosmos. Images that were previously seen as faint smudges of light by the Hubble Space Telescope were revealed to be detailed objects with structure and form. However, this discovery posed a challenge for astronomers as these early galaxies appeared too developed and large to have formed within the accepted timeline of the universe, leading to speculations that the big bang theory had been disproven.
In a recent article published in the Monthly Notices of the Royal Astronomical Society, researchers propose an alternative explanation. Rather than suggesting that the galaxies are too developed, the article argues that the universe might actually be twice as old as previously estimated, with an estimated age of 26.7 billion years. This bold claim is based on the concept of “tired light,” where light loses energy over time, causing distant galaxies to appear redshifted. According to this model, the redshift is not a result of cosmic expansion, but rather a natural process of light reddening over time.
The idea of tired light has been around since Edwin Hubble first observed cosmic expansion as a way to maintain the concept of a steady-state universe. Although it lost popularity as evidence for cosmic expansion became more compelling, the recent observations made by the JWST have revived interest in this alternative explanation.
The new study combines the tired light theory with the idea of changing physical constants. Physical constants, such as the speed of light or the gravitational constant, are believed to be innate properties of the universe and remain constant over time. However, the researchers argue that by introducing gradually shifting physical constants into the model, they can reconcile the observed redshift with the age of the galaxies, making them billions of years old instead of just millions of years.
While the model proposed in the article does fit the observational data, there are two major challenges to its validity. Firstly, it relies on tweaking the theories without strong physical motivations, which raises concerns about the robustness of the model. Additionally, the observations made by the JWST do not definitively rule out the standard cosmological timeline of 13.7 billion years. The complexity of the early galaxies can be explained by other mechanisms that do not require a complete rewrite of cosmology.
However, despite these challenges, the study is still valuable in terms of expanding our understanding of the universe. Thinking outside the box and considering alternative ideas helps to prevent scientists from becoming locked into outdated models. While it is unlikely that this new model will overthrow the well-established understanding of cosmology, the fact that it is testable and disprovable adds to the pool of ideas and possibilities for future research.
The findings of this study were published in the Monthly Notices of the Royal Astronomical Society.
Reference: Gupta, R. “JWST early Universe observations and ?CDM cosmology.” Monthly Notices of the Royal Astronomical Society (2023): stad2032.