Some time ago, if you told any space explorer that "our universe is expanding faster than light", they might have thought you were a character running out of sci-fi. However, with the advancement of science, this idea, which once sounded like fantasy, has now become the consensus of astronomy.
Imagine if the universe were a big party, and Earth would be the one forced to stand in the corner, because other galaxies were dancing in faster-than-light shoes, while Earth could only wear the "slow shoes" of light, watching the backs of other galaxies get farther and farther away. This is the current state of the universe in which we live: a cosmic "lost" story.
At the beginning of the 20th century, Edwin Hubble discovered that distant galaxies were moving away from us, and it was like being at a party where everyone quietly left you without you noticing. Albert Einstein, the brainchild of the party, didn't buy it at first, until he personally confirmed the phenomenon and had to admit that the rules of the cosmic party had changed.
Subsequent research revealed an even more striking fact: the dance steps of this party were faster than light. In other words, not only are galaxies moving away from us, but they are leaving at an accelerating rate. This leads to a problem: more than 94% of galaxies have traveled so far that our "light-speed shoes" will never be able to catch up with them. This faster-than-light expansion is like someone secretly speeding up the pace of ** at a party, making everything uncontrollable.
Dark energy, the mysterious DJ of this cosmic party, is the culprit for all this. It accounts for 70% of the energy of the universe, yet it is elusive and elusive. Dark energy provides a repulsive force that is the opposite of gravity, making galaxies farther and farther apart, like in a party where someone is constantly pushing away a dancing crowd and making it more and more difficult for everyone to contact each other.
But even in such a cosmic party, there are galaxies that defy the rules and collide and merge. The Milky Way and the Andromeda Galaxy are like two dance partners in the universe, decided at 37500 million years later, ignore the expansion of the universe and bravely step towards each other. This suggests that in some corners of the universe, the bonds of gravity are still strong enough to resist the thrust of dark energy, giving galaxies a chance to meet and dance together.
Unfortunately, despite such galactic mergers, the big picture is set: the universe is expanding at an accelerating rate. Every year, as many as 160 billion stars disappear from astronomers' field of view due to faster-than-light expansion. The galaxy of the future, like a forgotten balloon after a party, will eventually be torn apart by the inflating force and turned into stars scattered in space.
However, like any good party, this party in the universe also leaves us with countless memories and thoughts. It teaches us humility and makes us realize that we are only insignificant participants in this grand cosmic party. At the same time, it also stimulates our curiosity about the unknown, driving us to continue exploring the mysteries between galaxies that have "lost contact" and those that are still dancing with us.
So, the next time you look up at the night sky, imagine those galaxies dancing faster than the speed of light, and that mysterious DJ dark energy. The universe is a large and complex party, and we are fortunate to be invited to it. Let's cherish this opportunity and continue to explore, learn, and appreciate this spectacular cosmic party.