Five ways scientists think the universe could meet its end

Scientists have five possibilities for how the universe is going to end.

The end of the universe is probably not something we will have to think about in our lifetimes, by which I of course mean the life of the human species, at least you would hope so anyway.

But that hasn't stopped science with trying to come up with plenty of theories as to how things may play out in the extremely distant future.

Most of us have heard of the Big Bang, the moment when the universe erupted into existence.

Since then the universe has continued to expand, with gravity pulling matter together into galaxies, stars, planets, and occasionally elephants, which is really rather amazing when you think about it.

Eventually however, this must come to an end, and probably long after the Sun has expanded and swallowed up Earth.

So, order a drink, tuck into your steak from a cow that wants to be eaten, for the Douglas Adams fans, and let's take a look at the end of the universe.

What happens at the end? (Getty Stock)

The Big Crunch

This is one that you've probably heard of, and effectively works as the opposite to the Big Bang.

While the Big Bang threw everything outwards, the Big Crunch is going to see everything start to be drawn back in again.

Eventually all this would come together into one incredible ball of energy and matter where time doesn't even exist anymore.

The Big Freeze

This is where the universe effectively runs out of steam and stops expanding, but it doesn't move into a state of negative energy which would cause it to flip back into the Big Crunch.

As energy and matter are increasingly thinly spread this will lead to the universe's temperature gradually dropping down as entropy takes hold.

Eventually the universe will simply exist as a cold, dead space with the temperature hovering just above absolute zero.

So that's a cheery thought.

Could the universe begin again? (Getty Stock)

The Big Bounce

This is a slightly more optimistic approach to the Big Freeze which sees the universe eventually bouncing back.

Imagine another universe coming round in the same way as this one, with the final state eventually triggering another Big Bang.

The Big Rip

No, this isn't the result of having too many beans for dinner, instead it sees 'dark energy' growing in scale and magnitude.

This sees the universe scattered even further, until eventually even atoms themselves are split down into their constituents.

Finally the fabric of the universe itself will be ripped apart.

Vacuum decay

This is perhaps the most nihilistic of the five options we have here, for one good reason.

While the others are based on a very, very long-term idea of when the universe will end, this one is based on a terrifying idea that the 'quantum vacuum' which makes matter currently work the way it does may not even be its most stable state.

That means that it could decay into something else.

And if that happens, it effectively means that the universe would begin anew quicker than we could realize it was happening.

In layperson's terms - at any second the entire universe could just, stop existing.