Dark energy, a force making up 70% of the universe, continues to baffle scientists and along with dark matter, it leaves only 5% of the universe made of the matter we can observe, AFP reproted. 

Dark energy is believed to be responsible for the accelerating expansion of the universe, but emerging research suggests this theory may be up for debate.

What is Dark Energy?

No one fully understands dark energy. It’s invisible and doesn’t interact with matter or light. The mystery began with the Big Bang, when the universe started expanding. 

Joshua Frieman, a theoretical astrophysicist, describes a “cosmic tug-of-war” between dark matter, which pulls galaxies together, and dark energy, which pushes them apart. After 9 billion years of dark matter dominance, dark energy began accelerating the expansion. 

The breakthrough came in 1998 when astronomers discovered distant supernovae were farther than expected, revealing the universe’s expansion was speeding up.

Theories on Dark Energy

The dominant theory suggests dark energy originates from empty space itself. “If I remove all the particles from the cup of coffee, there is still energy in there due to what we call the quantum vacuum,” says Frieman.

However, new findings challenge this view. Recent data hints that dark energy might be weakening over time, which would invalidate the cosmological constant theory. “Empty space doesn’t change,” Frieman explains, suggesting other forces may be at play.

When will we know more?

Several new telescopes are now focused on dark energy. The Euclid space telescope, launched in 2023, is just one of many gathering crucial data. 

Future missions like NASA’s Roman space telescope (2027) and the Vera Rubin Observatory will also contribute. Frieman is optimistic about finding a “definitive answer” in the next few years, warning that “every minute we wait, galaxies are disappearing from view.”