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The Ultimate Fate of the Universe
For around 7.5 billion years, the rate of expansion of our Universe has been accelerating
Einstein and his Theory of General Relativity 1916
Einstein's theory showed that there were two possibilities for the fate of the Universe,
which depended on how much matter it contained .
This is not easy to calculate because of the existence of black matter . This is undetectable;
its presence is only revealed by its gravitational effects on normal matter nearby.
Recently, the presence of dark energy has been discovered. This adds to expansion by
providing a repulsive effect.
The fate of the Universe is dependent on its density. If the total mass of all the matter in
the Universe is exactly equal to the total force of expansion that is pushing this matter
apart, than equilibrium is reached. This is known as the critical mass .
Scenario 1 Big Crunch
If the mass of the Universe is larger than the critical mass, then the gravitational force will
eventually prevail. The expansion will slow until it eventually stops, and then the Universe
will start contracting under the effect of its own gravitation. The entire Universe would
collapse into an infinitely dense singularity .
This would require the geometry of space to be closed , like a sphere.
Bouncing Universe/Oscillating Universe
There might be an infinite sequence of finite Universes, each big crunch leading to another
However, this is unlikely due to Newton's second law of thermodynamics, as entropy
would build up and cause heat death .
Scenario 2 Big Freeze
If the mass of the Universe is lower than the critical mass, the force of expansion will win ,
and the Universe will expand forever.
This would require the Universe to have an open shape, like a saddle.
All the galaxies move so far away from one anther, The Universe becomes too cold to
sustain any form of life.
Phantom dark energy rips apart all material objects until they disintegrate into unbound
elementary particles and radiation. The end point of this is also a singularity.
Of the two, the open Universe model is more likely, based on the rate of expansion and
the mass density. This would make the `big freeze' scenario the most probable.
There is the possibility our Universe is one of many parallel universes, perhaps with
different physical laws. It may be that this universe ends but the multiverse as a whole
The fate of our Sun
Our Sun is around 4 billion years into its life cycle, around half way.
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When our Sun eventually becomes a red giant , life on earth will perish as a result of the
intense heat . If it survives this, it will perish in the cold and dark once the Sun becomes a
white dwarf. The prospect for humanity is bleak.
How does this challenge Xtian views on Salvation?
1. God designed and created the best possible world for us to live.
In Genesis, his Creation is lovingly created and pronounced as `very good'.…read more