Well, thank goodness for that. A new study has concluded that the end of the universe according to one theory isn’t due for 2.8 billion years – and it could last up to, well, infinity.
Okay, okay, that probably sounds a bit ridiculous. But there is some genuine science behind this. In a study, available on arXiv, researchers were investigating the supposed “Big Rip” scenario, in which the universe expands so much that space-time itself is torn apart. The study was picked up by Jacob Aron for New Scientist.
You might be aware that the universe is expanding at an accelerating rate. We know this thanks to observations of supernovae. The Big Rip theory is one of several theories for the end of the universe, which suggests that at some point the expansion will increase so much that all distances in the universe will essentially become infinite. Thus, all matter will be torn apart, and everything as we know it will cease to exist.
Whether the Big Rip happens or not depends on the amount of a mysterious force called dark energy in the universe. If the amount is increasing, the Big Rip could happen. If not, then another finale – such as a Big Crunch, sort of a reverse Big Bang, or a continual expansion towards a Heat Death scenario – is more likely to occur.
So the researchers decided to work out, if the Big Rip theory is true, when it might take place. They studied known expansion rates of galaxies and supernovae, in addition to data on dark energy, and came up with their figure of at least 1.2 times the age of the universe, or 2.8 billion years from now. Previous estimates had suggested a limit of 22 billion years.
“We’re safe,” co-author Diego Sáez-Gómez told New Scientist. Of course, we’ll also have to contend with the end of the Sun in 5 billion years, and the merging of the Milky Way and our neighbor Andromeda in 4 billion years.
Their upper limit for the Big Rip scenario is “infinity,” which would mean the rip never occurs, and instead the universe would die under the Heat Death scenario, where everything becomes so spread out that no new stars or other bodies can form.
For now though, you can rest easy that Earth isn't going to be destroyed by the universe tearing itself apart any time soon. We’ll just have to keep an eye out for other world-ending scenarios, like killer asteroids, instead.
[H/T: New Scientist]