Why Some Believe The World Will End In Ice

Earth, the Solar System, the Sun, and the Universe at large are not immortal entities, and one day, far into the future, existence will cease. The exact form of our universal demise is up to conjecture, but one theory, dubbed "The Big Freeze," has the most weight and support behind it (via Huffington Post). The universe is expanding — surprisingly, the expansion is actually accelerating — and could continue to expand indefinitely. This infinite growth will spread out everything, from molecules to stars, until every entity in existence is isolated from everything else and the universal temperature reaches absolute zero, the point where molecules stop moving. The entire universe will simply freeze.

Before the Big Freeze, galaxies will drift farther and farther apart until light no longer spreads from one to another. This stage has been dubbed the "Island Universe" as every galaxy will be completely alone, dark and isolated, drifting slowly toward an icy doom. It's a sad, lonely end to our universe, but one that humanity won't have to endure: we'll be long gone.

According to Wired, a major factor of the Big Freeze is entropy. Entropy is the measure of one of the laws of thermodynamics that says everything in the universe will slide from order to disorder. When entropy is at its peak, heat will be distributed evenly, and in a massively expanded universe, there won't be enough heat to go around. This leads to the ironically named "heat death," where all mechanical motion in the universe stops.

Gas in the universe would be spread extremely thin, so much so that there would be no hope for new stars to be born, and if there are no new stars, then that's it for the universe. Nothing would exist, just the endless march of time aging a world of nothing. If that sounds dark and gloomy, well, it is, but luckily this is only a theory, and one that would occur trillions of years into the future. Earth would have been swallowed up by the Sun eons ago by then, so the slow, cold lonely death of the universe isn't something that anyone on Earth, and perhaps any living thing, will have to experience.