Dark energy, an enigmatic force constituting approximately 70% of the universe, remains one of the most profound mysteries in science. Alongside dark matter, which makes up about 25%, only 5% of the universe is composed of visible matter, according to AFP.
Dark energy is credited with driving the accelerated expansion of the universe. However, recent findings are challenging established theories, compelling scientists to reconsider their understanding of this elusive phenomenon.
What is Dark Energy?
The true nature of dark energy remains unknown. It does not interact with light or matter, and some even question its existence. The concept traces back to the Big Bang, which occurred 13.8 billion years ago. Joshua Frieman, a theoretical astrophysicist, explains that while dark matter pulls galaxies together, dark energy pushes them apart. For the first 9 billion years, dark matter dominated, but dark energy eventually took over, accelerating the universe’s expansion.
In 1998, astronomers observed that distant supernovae were farther away than anticipated, confirming the universe’s accelerating expansion. This discovery led to the identification of dark energy as a key component of the cosmos.
Theories About Dark Energy
The prevailing theory suggests that dark energy originates from empty space. Frieman explains, “If I remove all the particles from a cup of coffee, there is still energy in there due to what we call the quantum vacuum.” However, recent studies indicate that dark energy might be weakening over time. If confirmed, this would upend the current cosmological model. Frieman notes, “Empty space doesn’t change,” implying that dark energy may not be a constant force.
When Will We Learn More?
Cutting-edge telescopes are poised to unravel the mysteries of dark energy. The Euclid space telescope, launched in 2023, along with future missions like NASA’s Roman space telescope (set for 2027) and the Vera Rubin Observatory in Chile, are gathering crucial data. Frieman anticipates a “definitive answer” within the next few years. He cautions, “Every minute we wait, galaxies are disappearing from view,” emphasizing the urgency of these investigations.
As scientists continue to explore the universe’s deepest secrets, dark energy remains a central puzzle, with the potential to reshape our understanding of the cosmos.
