How will it all end?
Like all living things, it is normal to think that the universe also has an end. Surprisingly our current theories are able to make that exact predictions about the universe’s death.
Cosmologists can observe two important things: One, the universe expanded faster and faster, and the next is, its energy resources are limited. This means that the stars in the distant future will die one by one, so that in the end, it will be only small, red dwarf stars remain. They also convert hydrogen so slowly that some can live for over 100 million years.
Even further into the future, galaxies fly apart faster and faster, and with time it will almost be no star remains in the visible universe.
Meanwhile, Planetary systems inside these galaxies also start separating each other. Some of their stars closer to the center swallowed by the black holes at their centers, while others are thrown out into the great void. In the end it will only remain scattered black holes and dead stars in a completely dark universe. If you go further into the future, cosmologist propose few models on, how this remaining energy or matter will end up with.
Some are suggesting the ever increasing dark energy will rip off remaining stuff in to smallest component of sub atomic units as known as the Big Rip. Another theory suggest that the expanded universe cooled down by emitting radiation in to expanded space and die in Heath Death.