Edwin Hubble made the fantastic discovery that we are in just one of many galaxies. Not only that, but most galaxies are moving away from each other at an accelerating pace. Like stars on an inflating balloon, we are getting farther from our neighbors. Space itself is expanding.
Does this mean that we are in a sense bigger than we used to be? Theories suggest that a possible outcome of a universe that is going through accelerated expansion is something called entropy death, otherwise known as the heat death. If we truly are moving farther and farther from other galaxies, and the stars themselves are moving farther apart, then we would one day see nothing but blackness in the night sky. Stars once present in our view will eventually be so far away that light would not be fast enough to reach our eyes due to the extreme distance and the accelerating speed of the stretching of the cosmos. Even the stars themselves would run out of fuel and the last light would flicker out. Black holes would evaporate due to Hawking radiation, then after eons all that is left is a cold coordinate system with nothing interesting going on.
Is this how it ends?
We like to assure ourselves that our warm, stable existence would at least carry on for several millennia until anything earth-shattering may occur (and even quite longer than that if we are talking entropy death) but is that really reassuring? Is this doom inevitable? Certainly this is just one possible fate, but according to most accepted models and theories, it's doom one way or the other.
Occam's razor suggests we go with the most plausible theory, but all theories seem implausible. Life itself is quite amazing. Looking at the advancements of mankind in our brief history on this cosmological scale puts our view I to perspective. There is more to the story, whether it be a theory related to holography, Everett's many world's, simulation theory, dark matter, or someone simply needs to flip over to side B, science at the present has run into an ontological conundrum. We can only live so large in an expanding universe.
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