Exciting new evidence suggests dark energy, the mysterious force pushing the universe apart, might not be as constant as we thought. Recent observations from the Dark Energy Survey (DES) and the Dark Energy Spectroscopic Instrument (DESI) show that dark energy could be changing over time.
If true, this challenges our basic understanding of dark energy, particularly the idea of the cosmological constant, which has long been accepted. This shift opens the door to fresh theories about how the universe works.
One emerging idea involves a new model that includes two components driving dark energy. The first is an axion, a light particle that rarely interacts with regular matter. These axions could fill the universe, contributing to its accelerated growth. The second component is a revised cosmological constant, set to a lower value. Research indicates that these axions and the cosmological constant might work together, explaining current observations from DES and DESI.
The new model suggests a phase where axions dominate. However, these particles will eventually lose their influence, allowing the cosmological constant to take over. As this happens, the universe’s expansion could slow down, leading to a reversal that resembles a “Big Crunch,” where everything collapses back together.
Interestingly, experts predict this reversal might begin in about 10 billion years. By that time, the universe will have spent another 10 billion years shrinking, ultimately ending in a dense, hot singularity. For some context, this timescale is shorter than the current age of the universe, which is about 13.8 billion years.
This theory is, however, still in its early stages. The findings from DES and DESI are preliminary and require more study. Even if further research shows the cosmological constant is insufficient, it won’t automatically validate this new model.
Regarding public interest, discussions around dark energy and the possibilities of a Big Crunch have been trending on social media. Many users express both curiosity and skepticism. As we continue to explore this fascinating topic, it’s clear that our understanding of the universe remains a work in progress.
For more detailed studies, you can check resources like the [NASA website](https://www.nasa.gov) or the recent paper on dark energy models available on [arXiv](https://arxiv.org/pdf/2506.24011).
