zoom_in Click to enlarge

Dark energy

▲ ▼

description Dark energy Overview

Dark energy represents an unknown form of energy that dominates the universe. It’s responsible for the observed acceleration in the expansion of space. Cosmologists study it to understand the ultimate fate of the cosmos and its large-scale structure. This concept is vital for investigating our understanding of gravity, vacuum energy, and the evolution of the universe.

help Dark energy FAQ

What observation first showed that the universe's expansion is accelerating?

Two research teams studying distant Type Ia supernovae reported in 1998 that the explosions appeared dimmer than expected in a slowing universe. The result implied accelerated expansion and led to the 2011 Nobel Prize in Physics for Saul Perlmutter, Brian Schmidt, and Adam Riess.

Is dark energy the same thing as dark matter?

No, dark matter gravitates and helps bind galaxies and clusters, while dark energy is the name given to whatever drives accelerated cosmic expansion. In the standard cosmological model, dark energy accounts for roughly two-thirds of the universe's total energy density.

What does Einstein's cosmological constant have to do with dark energy?

The cosmological constant, written as Lambda, represents a constant energy density built into empty space. It is the simplest explanation used in the Lambda-CDM model, although its extremely small observed value remains difficult to reconcile with quantum-field calculations.

Could dark energy eventually tear apart galaxies and atoms?

A hypothetical Big Rip could occur if dark energy had an equation-of-state parameter below minus one and grew stronger over time. Current observations remain broadly compatible with a cosmological constant, which would instead produce continuing acceleration without ripping apart bound systems.

swap_horiz

Looking for Dark energy alternatives? Compare top competitors ranked & scored

arrow_forward