Scientists have observed the early universe running “five times slower” than the present. The study, led by Prof Geraint Lewis from the University of Sydney, utilised data from quasars, distant celestial objects powered by supermassive black holes at the centres of early galaxies.

Quasars have long captivated astronomers for their extreme brightness and remote locations, making them invaluable tools for studying distant cosmic eras. These celestial objects are powered by supermassive black holes, consuming surrounding gas, dust, and matter, releasing tremendous energy in the process.

Professor Geraint Lewis, along with astrostatistician Brendan Brewer from the University of Auckland, embarked on the comprehensive study spanning over two decades. This study analysed the colours of nearly 200 quasars. Standardising the “ticking” of each quasar for their observations, the researchers focused on a time when the universe was just over a billion years old, shortly after the Big Bang.

Albert Einstein’s relativity theory has been further affirmed through observations. Since the universe’s inception in the Big Bang singularity, time and space have been intricately intertwined. The expansion of space plays a significant role in shaping our reality.

As the universe expands, galaxies move farther away from one another, creating more space between celestial bodies. This expansion of space influences time itself, leading to the phenomenon observed by researchers. Hence, when gazing back in time to the early universe, its flow appears to decelerate dramatically due to this ongoing expansion.

Previously, astronomers had confirmed the early universe’s “slower” effect using distant supernovae, enabling them to glimpse back in time to approximately half the universe’s age. However, the recently published study utilising quasars has pushed the boundaries even further, reaching back to approximately a tenth of the universe’s age. This extension in time scale provides scientists with an expanded canvas to paint a more comprehensive picture of the universe’s evolution.

In an interview on BBC Radio 4’s Today programme, Prof Geraint Lewis explained how the universe’s expansion would perpetuate indefinitely, causing the cosmos to grow larger and emptier over time.

With this newfound knowledge, astrophysicists are now better equipped to explore the universe’s ancient history and eventual fate.