As compicated as it may sound, in 100 million years, the universe could start to shrink, which according to researchers, is "remarkably soon." Per research published in the journal Proceedings of the National Academy of Sciences, experts have discovered that after 13.8 billion years of the universe expanding, there could be a time it will come to a standstill - and then contract.
A team of scientists recently gathered together to get down to the bottom of this. They specifically researched the nature of dark energy - a force that causes the universe to expand faster and faster. However, in the team's model, dark energy did not act as a constant force of nature but rather as an entity named quintessence, making it decay over time. In their study, the group of researchers hypothesized how the existing properties of quintessence could change over the next billions of years by creating a physical model of the entity. "To their surprise, dark energy in their model can decay with time," one researcher said. "Its strength can weaken. And if it does so in a certain way, then eventually the antigravitational property of dark energy goes away, and it transitions back into something that's more like ordinary matter."
The team's model predicted the mysterious dark energy force could have begun billions of years ago and now is weakening. Additionally, these scientists say the acceleration of the universe could potentially end within the next 65 million years, and then within 100 million, the universe's cosmic expansion could stop altogether. With the universe's acceleration ending, it could enter an "era of slow contraction," ending billions of years from now with the death-or-rebirth of space and time.
According to co-author of the project, Paul Steinhardt, "On a cosmic scale, 65 million years is remarkably short," considering that 65 million years ago, the Chicxulub asteroid hit the Earth and eliminated all dinosaurs! Researchers who were not involved in the study agree that there is nothing controversial about this theory due to the universe's mysterious nature behind dark energy. So, for now, these theories will remain theories, and the cosmic universe as we know it will continue to expand (or not)...