G. Mustafa

The universe is expanding, and the pace of that expansion is set by dark energy, the mysterious force accelerating the recession of galaxies. In the standard cosmological model, its density is constant: a cosmological constant, an unwavering metronome since the birth of the cosmos.

The universe is putting on a show, and the lead role goes to dark energy. For a long time, the actor seemed unchanging: the cosmological constant (the vacuum energy that accelerates cosmic expansion) set the same tone throughout.

The Universe is a grand highway where galaxies, like cars, are moving apart faster and faster. The gas pedal is controlled by mysterious dark energy.

Picture the early Universe as an unimaginably large bell. Inflation — the era of rapid expansion, dreamed up by Alan Guth, strikes it, sending a wave rippling across the fabric of spacetime.