Study reveals ‘death date' of the universe before ‘Big Crunch' occurs

News.com.au

08-07-2025

Time to get your affairs in order — we only have 20 billion years left.
That is according to researchers who have published a new study claiming that our once-believed ever-expanding universe will actually begin to shrink in seven billion years.
The study, which was published by physicists from Cornell University, Shanghai Jiao Tong University, and other institutions, suggests that the universe will reach a peak size.
After that point, the universe will begin contracting until everything collapses back into a single point.
It's essentially a reverse Big Bang, which scientists have dubbed the 'Big Crunch'.
Using data from a number of astronomical surveys including the Dark Energy Survey and the Dark Energy Spectroscopic Instrument, the researchers predict that this 'Big Crunch' will occur in approximately 33.3 billion years.
With the universe currently 13.8 billion years old, this gives Earth and everything else roughly 20 billion years before entering oblivion, according to the study.
And considering the Earth is expected to be engulfed by our dying sun in approximately seven billion years, it's probably not something anyone will have to worry about too much.
The theory is that the universe expands like a 'rubber band' – eventually, the elastic force becomes stronger than the expansion, causing everything to snap back together.
The researchers' theory hinges on dark energy, a mysterious force that makes up about 70 per cent of the known universe.
Dark energy has long been believed to be the driving force behind the expansion of the universe.
However, recent observations suggest the force might actually be dynamic – meaning it can only expand so much until it shrinks again.
The new model proposed by researchers suggests the universe will continue expanding but at a gradually slowing rate.
At its maximum size, about 69 per cent larger than the size it is today, a gradual contraction will begin.
Several major astronomical projects launching in the coming years aim to provide more information on the behaviour of dark energy.
These missions could confirm or rule out a 'Big Crunch' scenario.
Even if the terrifying outcome is confirmed, a 20 billion year countdown is hardly a reason to panic.
For context, complex life on Earth has existed for only about 600 million years – a fraction of time in comparison.
20 billion years down the line, the Sun will have died and our galaxy will have collided with the neighbouring Andromeda galaxy long before 'the great end'.
The prediction also comes with a significant level of uncertainty.
The researchers have acknowledged that their model has large margins of error due to limited observational data.
So, alternative scenarios – including eternal expansion – are still possible.