A recent study based on observations from space has provided renewed support for a centuries-old theory that challenges the widely accepted Big Bang model.
The findings, published in the magazine particlessuggest that the ‘aging light’ hypothesis may be correct, casting doubt on the belief that the universe is expanding.
The study authors used data from multiple telescopes to analyze more than 30,000 galaxies and measure their redshift – the phenomenon in which light shifts toward the red part of the electromagnetic spectrum as an object moves away from Earth. Redshift has long been used by astronomers to estimate the speed at which galaxies are moving away from us.
In the 1920s, astronomer Edwin Hubble discovered that galaxies farther from Earth appear to recede faster, leading to the development of the Big Bang theory. According to this model, the universe has been expanding since its origins about 13.8 billion years ago.
However, around the same time, Swiss astronomer Fritz Zwicky proposed an alternative explanation for redshift, known as the “aging light hypothesis.”
Zwicky suggested that galaxies weren’t actually speeding away from Earth; instead, the photons emitted by these galaxies lost energy as they traveled through space.
In other words, the redshift was due to the ‘aging’ of photons over large distances, and not to the motion of the galaxies themselves. According to this hypothesis, the universe is not expanding, but is static.
Zwicky’s theory was largely rejected for almost a century in favor of the Big Bang model, which gained wide acceptance. But the launch of the Webb Space Telescope in 2022 has some astronomers reexamining the big bang theory.
The telescope has provided new data that challenges current cosmological models, including images of fully formed galaxies that appear to exist just a few hundred million years after the supposed birth of the universe. These galaxies would have taken billions of years to evolve, which would cast doubt on the timing and nature of the Big Bang.
Using Webb’s data, the researchers behind this new study analyzed the redshift of galaxies moving at different speeds relative to Earth.
They found that galaxies orbiting in the opposite direction of the Milky Way have a smaller redshift than galaxies orbiting in the same direction. The difference in redshift increases as the distance between Earth and these galaxies increases.
According to the study, Earth’s rotation speed relative to distant galaxies is constant, but the variation in redshift is due to the galaxies’ distance from Earth. This finding supports the aging light hypothesis: the redshift is not due to galaxies moving away, but rather to the gradual loss of energy by photons over time.
