The skies of the future will be much darker as more and more galaxies fall beyond our event horizon. observes a Harvard Smithsonian scientist quoted in Nature magazine.
The universe will expand forever. This is what John Weitfeld claims, in an article published in the journal Nature.
Astronomers working 100 billion years from now will experience hard times. Only a thousand galaxies will be observable from the Milky Way. (Earth itself will have ceased to exist long before that). This is compared to the billions of galaxies visible today. Their image will also be frozen in time and not changing, only dimming.
Fate is a consequence of the phenomenon of the universe expanding forever, says Abraham Loeb of the Harvard-Smithsonian Center for Astrophysics. The celestial objects will move so fast from us that the light coming out of them will not be able to reach us (of course it is not necessary that they move at the speed of light, it is enough that they move at slightly more than half the speed of light and the Milky Way will move at the same speed in the opposite direction).
The more distant the objects, the faster they will escape from our horizon. In 50 billion years the universe beyond our local group of galaxies will stop changing. The most distant celestial object known today, a quasar that is 13 billion years away from us will freeze when it reaches 6 billion years old, about the age of our Sun today. "There is a finite amount of information that can be collected about the universe," says Laub. "We will never know how it developed beyond a certain stage."
Is the universe expanding forever?
"The universe has been expanding since the big bang. Until recently, most cosmologists assumed that the gravitational force between galaxies might slow down the expansion, or even reverse it and lead to the big crash. But in recent years, observations of distant exploding stars have led scientists to assume that the expansion is accelerating and carrying everything away from everything else.
The further away a bone is, the faster it recedes. The faster it recedes the slower it changes, at least as far as we can see. Finally it will seem as if time has stopped. The objects will reach the event horizon, like objects falling into a black hole - beyond the place where light can reach us. As areas pass beyond the realm we can see they will also cross the threshold of the place where we can think about them. says the astronomer Martin Rees (Martin Rees) from the University of Cambridge. "It is a question of at what point the invisible parts of our universe cease to be part of science and become metaphysics." He says.
Finding the cause of the cause of the universe's expansion is "the greatest challenge of cosmology," says Laub. "A continuum cosmology may result in a vacuum in space or dark energy that pushes objects apart. Or something that changes over time may cause acceleration.”
In the second case, the expansion may slow down, and the future universe will not be so dark and lonely. But this change has to happen quite quickly, says Laub, adding that it will no longer be possible to slow down the universe when it reaches five times its current age.
