The accelerating expansion of the universe is usually explained by an invisible force known as dark energy. But a new study suggests this mysterious ingredient may not be necessary after all. Using an ...

Understand the energy density of electric and magnetic fields by exploring how energy is stored and distributed in electromagnetic fields. This video explains the underlying physics, key equations, ...

Dark energy—the term used to describe whatever is causing the universe to expand at an increasing rate—is one of the universe’s greatest mysteries. The most widely accepted theory currently suggests ...