How Long Will the Universe Exist?
Scientists have tried to figure out how long the universe will exist, but they haven't been able to agree with one another yet.
Some scientists believe the universe will go on forever, even after all the stars are burnt out. The universe will then be completely dark and cold for the rest of time.
But other scientists believe that the universe will someday explode and start all over again. Right now, the universe is getting bigger, and all the stars are getting farther apart from one another.
Perhaps at some time in the distant future, the universe will begin to grow smaller, and all the stars will move toward one another. After many millions of years, all the matter in the universe will be crushed together in a small area, and then it will explode again — beginning the universe all over again!
Scientists have no way of knowing if the universe has already expanded, shrunk, and exploded many times!
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How Long Will the Universe Exist
I have the answere,
Scientist have been mind boggling & disagree with one another coz they have no knowledge of it.
The earth & the heavens (stars & galaxies) are initially a one piece,as a whole.Then it is separated by some forces,not by a big bang.If it is separated by a big bang ,then I'am not talking right now.Everything will be in pieces.The big bang is only a lame theory.And also if it is triggered by a big bang,no traces of this beautiful earth is left now.And the theory that the universe is expanding & later contracting is just yet to be prooved.How do one proove the universe is expanding.Who assume that everything will be pulled back to the centre of gravity or the same centre if explosion or big bang happens?There will be no more centre of gravity at the centre of explosion.The universe will surely came to an end but nobody knows when but its not far from now.All the stars & galaxies will eventually lose their energy & collapse & that is the time when the universe came to an end.
Expanding universe
Until quite recently the thinking went a bit like this: If it all started out as a point and there was a big explosion, then the universe's center of gravity would located at that point, which would also be the geometrical center of the universe, since there is no "preferred direction" in which blasted matter would move.
This means that as the universe expanded all the matter going outwards would be slowed down by gravity pulling towards the center. When it became clear that the universe is expanding the question naturally popped up: As galaxies move farther and farther apart, the gravity pulling towards the center would always tend to slow them down, but this "brake" would become weaker and weaker at the same time. So three possibilities seemed to exist:
1) The universe continues to expand forever.
2) A perfect balance is reached at some point where the universe stops expanding but does not contract.
3) The universe starts to contract and then all matter would accellerate inwards for billions of years until the "big crunch" - the opposite event of the "big bang".
It may seem, intuitively, that 3) is the only possibility given that there's a force acting towards the center that will never go away and no force pushing outward. But the math works. You can think of it a bit like when we launch stuff from Earth. Close to the earth the gravity field is so dominated by our planet that we can ignore the influence of other matter for the purpose of illustration. If we send something up at a very high speed, like a rocket, it can completely escape earth's gravity field so it will never return. That's the "forever expand" option. If we send it at just the right speed it goes into orbit around the earth, neither moving away nor closer. (In practice it doesn't quite work this way; our oldest sattelite the moon is actually moving closer due to loss of energy because it's gravity moves the oceans on earth back and forth. The same would happen, though to a much lesser extent, to any other mass in orbit.) Finally, if we throw something up at a lower speed it will continue to rise while losing speed until it reaches zero speed and falls back to the ground.
However, this so far comfortably logical view of things took a very interesting turn when it was discovered that not only is the universe expanding, but the rate of expansion is actually increasing! There are no widely accepted explanations for this yet, but it led to theories about "dark matter" and "dark energy", so called because we cannot observe them directly, only infer their existence from the effects they have on what we *can* observe!
The universe is a wonderous, beautiful, and deeply mysterious place!
Moon moves away from Earth.
Moon moves away from Earth.
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