According to recent dark energy results, a new model finds that the Universe has a lifespan of only 33.3 billion years. Since we are now 13.8 billion years after the Big Bang, this suggests that we have just under 20 billion years left. According to studies, the ultimate fate of the Universe depends on dark energy and the cosmological constant λ.
Although it was previously believed that the universe would continue to expand indefinitely, new studies by physicists Hoang Nhan Luu from the Donostia International Physics Center in Spain, Yu-Cheng Qiu from Shanghai Jiao Tong University in China, and the corresponding author Henry Tye from Cornell University in the United States indicate that the universe will eventually stop and reverse its direction, leading to the hypothetical Big Crunch.
These conclusions have been made possible by the introduction of a second component in this process: the axion field. Axions, which are responsible for pushing the universe outward, are expected to lose their strength and gradually weaken, favoring the reversal of the Universe’s expansion.
New theory on the behavior of the universe
Contrary to what was expected, the new calculations have indicated that the universe appears to have an expiration date. According to the data, the new model proposes a total lifespan of the universe of 33.3 billion years.
This means that 13.8 billion years have already passed since the Big Bang occurred, leaving us with 20 billion years of life. According to physicists Hoang Nhan Luu from the Donostia International Physics Center in Spain, Yu-Cheng Qiu from Shanghai Jiao Tong University in China, and the corresponding author Henry Tye from Cornell University in the United States, “For the past 20 years, people have believed that the cosmological constant is positive and that the universe will expand forever,” says Tye. “The new data seems to indicate that the cosmological constant is negative, and that the Universe will end in a big crunch”.
Cosmological constant λ
The cosmological constant was introduced by Albert Einstein in his theory of general relativity to describe the expansion of the Universe. According to this theory, if the value of λ is positive, it acts as a force that pushes outward. Conversely, if it is negative, its behavior is completely opposite: it acts as a pull inward, which could stop and reverse the expansion of the universe.
New agents
To explain this theory, Tye and his team have introduced a variable: axions. According to them, axions are capable of acting like an outward-pushing force, but they gradually lose power. At the current stage of the universe, the researchers indicate that the influence of the axion is still strong, so the Universe is still accelerating today in this scenario. However, it is believed that when 11 billion years have passed, the push of λ will weaken enough for the negative value to come into play, and the process of contraction of the Universe toward the Big Crunch will begin.
Physicists have made a comparison between the timeline that the universe is going through and the action of axions, to riding a bicycle up a hill with a tailwind (the axion). The wind calms down, you reach the top (maximum expansion), and then you let yourself go down the slope (the contraction driven by negative λ and gravity).
It’s only a possible scenario
It is important to clarify that this is just one of the possibilities proposed for the future of the organism, but it is not a certain prediction. To be able to state that the behavior of dark energy is changing, much more information and more precise data would be necessary.
Nevertheless, this research, which has been published in the Journal of Cosmology and Astroparticle Physics, “For any life, you want to know how life begins and how life ends – the endpoints,” says Tye.”For our universe, it is also interesting to know, does it have a beginning? In the 1960s, we learned that it does have a beginning. So the next question is: ‘Does it have an end?’ For many years, many people thought it would continue forever. It’s good to know that, if the data holds, the universe will have an end.