NASA, ESA, CSA, STScI
In a sense, we are at the center of the universe. But that’s because we see the same distance in every direction, and the observable universe is perfectly spherical. Due to the limitations of the speed of light and the inexorable expansion of the universe, we can see about 46 billion light years away in every direction. What is beyond this horizon? That is a mystery that will never be solved.
But there are clues. The overall size of the universe is governed by two competing effects: gravity and dark energy. All matter has mass, which causes gravity, pulling everything to everything else. But to their surprise, early 20th-century cosmologists discovered that distant galaxies appear to be moving away from us at incredible speeds. The mysterious force that causes this strange expansion of space is called dark energy, and its nature remains a mystery to this day.
“Before we discovered dark energy and accelerating expansion, the universe was much simpler,” the cosmologist says. Wendy Friedman Researchers at the University of Chicago say that without dark energy, the universe would be much smaller, making its size easier to predict.
Even with dark energy, the universe may only be slightly larger than we can see. Jean-Luc LehnersHe then worked at the Max Planck Institute for Gravitational Physics in Germany. Jerome Quintin University of Waterloo, Canada The model was published It suggests that the period of rapid expansion just after the Big Bang, the so-called inflation, may have been even shorter than we thought, making the universe smaller…
Source: www.newscientist.com
