Death of the universe?(2)
In this scenario, the universe could return to its original state just before the Big Bang setting the stage for a perpetual seesaw of creation ang destruction. The Big Crunch theory moved to a scientific backburner. Cosmologists worked out that there must be some form of energy that keeps the universe from collapsing.The existence of such a force leads to new theories about what the universe is made of and how it might end. And evidence about how this might play out is found in some of the most powerful and mysterious phenomena in the cosmos...Black Holes.
Predicting how the universe will end involves some of the most advanced technology known to man. On a remote volcano on the island of Hawaii, astronomers are monitoring a battle in space that is shaping the fate of the universe. At an elevation of nearly 4,300 meters, the Keck Telescopes bring astronomers from all over the world nearer to space for a clearer view of the cosmos. They come here because the telescopes work best far away from city lights and as high as possible above the Earth's polluted air.
Harsh conditions make it difficult to work here. But for scientists in pursuit of the great mysteries above, it's paradise. So, this is a remarkable location. But of course the air is very thin, it's extremely hard to work here. But these telescopes are amazingly powerful. But we're ambitious astronomers. We don't just start looking at easy objects. We try hard to look at the very faintest objects so we can understand the extremities of the universe, the most distant objects that tell us about the universe when it was very young.
Here, astronomers like Richard Ellis are working on a problem that has been all consuming for cosmologists since Edwin Hubble. They know the universe is expanding. But what they don't know is how fast It will be difficult to predict exactly how the universe will end until they solve this mystery. The answer lie in the past.
An astronomer like myself uses a ground-based trlescope as a time machine. We're looking back in time to study distant galaxies seen us they were a long, long time ago. Richard Ellis, and scientists like him, train their telescopes on light from the past. They're seeing things that validate long-standing theories about the cosmos by observing objects that technology has only recently been able to see.
And what astronomers are finding is that one of Einstein's predictions in particular, just might be responsible for the crushing end of the cosmos. Einstein said that there has to be more mass in the universe than we can actually see. He predicted that there would patches of invisible supergravity from which not even light could escape. One of the distant galaxies that astronomers found revealed a powerful source of X-rays from something that they could not see. It was in the Constellation Signus and emitted no light. But something was there. Whatever was emitting these x-rays had a mass about seven times that of Earth's sun. There wasn't a name for it, so they called it a Black Hole.
Black Holes offer scientists an analogy to how the Big Crunch Theory works. When certain stars run out of fuel they collapse in on themselves into a smaller and far denser mass that attracts more and more matter, just like the Big Crunch.
The gravitational pull is so powerful that anything that falls near a Black Hole will be forever trapped. Not even light can escape. It's a mind-boggling concept that something invisible is detectable and offer a view to our ultimate fate. This black trap represents space. And space is relatively flat.But when you put a massive object into space it curves it.This is a penny.And notice how it comes into a really beautiful circular orbit. Basically, the Black Hole trapped it into an orbit around itself. And that orbit becomes very circular as it gets closer. And now the penny will eventually disappear, go inside the Black Hole. What if our universe eventually collapsed upon itself? What if eventually all of the matter in the universe were enough to gravitationally pause it to collapse into one huge Black Hole? Then at the end you would end up with a big singularity. So that's one possible future of the universe that we end up in a singularity. We came from one, we might go into one and that's one way you can look at it on a big macroscopic scale, that Black Holes, in some ways, their physics is very similar to what started the universe. And so, that may be how we end up.
Black Holes exist in isolated areas througout the cosmos. A black Holes' gravitational pull is a scaled down version of the force that could cause the universe to collapse. That force is dark matter. And dark matter is what scientists often call cosmic glue. Dark matter, attracts other objects while its gravitational attraction is a positive force. Dark energy, we don't really understand what it is but it's negative repulsing effect that pushes galaxies away from each other.
The whirlpool in Richard Ellis's demonstration represents the gravitational force of dark matter. The green dye coming out of the syringe shows how the stuff of the universe collapses under the force of dark matter. The presence of dark matter acts as the focus for the gas in the universe, bringing structure together. This is how the Milky Way developed as the universe expanded. Little things merging into big things. The positive constructive force of gravity. Now if this was the only force in the universe and the universe would stop expanding at some point in the future and eventually the universe would stop collapsing, gravity would eventually halt the expansion and bring it back together in a Big Crunch.
Death of the universe?(1)
Death of the universe?(3)
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