About 13.8 billion years ago, a tiny but dense ball of fire gave rise to a vast cosmos containing trillions of galaxies, including the Milky Way. But according to new research, our universe is dying, and it’s happening much faster than scientists previously thought.
The last stellar remnants of the universe will cease to exist in 10 to the power of 78 years (that’s one with 78 zeros), according to new calculations by a team of scientists at Radboud University in the Netherlands. The moment when the universe shuts down forever is still a long way off, but it is a much earlier moment than the previous estimate of 10 to the power of 1100 years.
The new paper, published Monday in the Journal of Cosmology and Astroparticle Physics, is a follow-up to a previous study by the same group of scientists. In their 2023 study, black hole expert Heino Falke, quantum physicist Michael Vondrak, and mathematician Walter van Suilek suggested that other objects, such as neutron stars, could evaporate in the same way as black holes. The original theory, developed by Stephen Hawking in 1974, suggested that radiation emanating from near the event horizon of a black hole gradually erodes its mass over time. This phenomenon, known as Hawking radiation, remains one of the most fascinating ideas about black holes to this day.
Based on Hawking radiation theory, the researchers of the new paper suggest that the erosion process depends on the density of the object. They found that neutron stars and stellar black holes decay in about the same amount of time – about 10 to the power of 67 years. Although black holes have a stronger gravitational field that should make them evaporate faster, they also have no surface, so they end up reabsorbing some of their own radiation, “which slows down the process,” Vondrak said in a statement.
The researchers then calculated how long it would take for various celestial bodies to evaporate due to Hawking-like radiation, leading them to a shortened cosmic shelf life. “So the final end of the universe will come much sooner than expected, but fortunately it will still take a very long time,” Falke said.
The study also estimated that the Moon would take about 10 to the power of 90 years to evaporate, based on Hawking radiation. “By asking questions like this and looking at extreme cases, we want to better understand the theory and maybe one day unravel the mystery of Hawking radiation,” van Suylekom said.
