In my last post, I wrote about the end of our universe. I wrote about 2 different ways our universe could end in ( refer the link; When The Universe Banged: Part 1 and When The Universe Banged: Death Of Our Universe (Part 2) ).
The first way I suggested was THE BIG CRUNCH where our universe would collapse to singularity. I also mentioned about inability of gravity to contract the universe and only by reversing the time we can take our universe to the very beginning of it. By reversing the time we can reverse process of expansion into contraction.
Now there is a flaw in this approach. It contradicts the laws of thermodynamics and the law of probability (it actually violates law of probability and intern violate the law of thermodynamics. Refer this link for a clear understanding; Entropy and Universe.). But still it could be possible only if the laws of physics get altered when time reverses.
Another way in which our universe could end in is related to dark energy. Dark energy is something which is responsible for expanding our universe. (i am using something as we still are unaware of what it is. It may be an energy or something else, however we do know that it exist. Refer; Dark Energy Does Exist, Einstein Was Wrong ). It separates every galaxy out there in space and make them move away from each other.
With time dark energy will slowly move everything away, the galaxies, the stars, planets and eventually the subatomic particles themselves. This will be a slow and cold death of your universe. Either way it goes, one thing is for sure, our universe will end one day.