The End of Time is Nigh (in a Cosmic Sense, Anyhow)

The End of Time

Ticking off the seconds until the end of time, some 3.7 billion years from now.Leo Reynolds via Flickr

The universe has only about 3.7 billion years in which to settle its affairs. At least, that's the new assertion from a group of physicists who say that there is a 50 percent chance that time will end within that time frame. If the laws of physics as we understand them are in fact correct, then time must eventually end – and their math shows that both the sun and the Earth should still be around when that happens.

Why? Physics tells us that the universe has been expanding since the Big Bang some 13 billino years ago and that it is still expanding to this day (Did you just feel that? That was the universe expanding around you). But there's a problem: if the universe expands infinitely, then every conceivable event – no matter how un-probabilistic – will occur. In an infinite universe, in fact, the most improbable event will happen an infinite number of times.

The idea of being unable to determine the probability of anything, as would be the case under such circumstances, pretty much pulls the rug from under modern physics, rendering them meaningless. In other words, even though physics tell us that the universe is eternally expanding, physics itself is untenable in such a universe.

So in order for physics to have meaning, time must end at some point. According to the mathematical crunching of UC Berkeley's Raphael Bousso and colleagues, there's a 50 percent chance of that happening in the next 3.7 billion years. That's Biblical in a sense, if only because the Earth and Sun will likely still be around when the end of time comes. But, says Bousso, it's unlikely we'll see the end event coming before it dismantles life, the universe, and everything.

Of course, this entire analysis concerning the relevance of physics assumes physics are relevant, which is a philosophical rather than a scientific argument, as Tech Review points out [read more]. Perhaps the laws of physics just work and we don't need to understand – and possibly can't even fathom – why they work they way they do. If that's the case, the argument that time must end in the first place is flawed.

Put another way, live every day like time might cease some 3.7 billion years from now. Because maybe, just maybe, it will.