Matter & Energy News -- ScienceDaily

• A new theory of gravity could explain cosmic acceleration without dark energy
  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 extended version of Einstein’s gravity, researchers found that cosmic acceleration can arise naturally from a more general geometry of spacetime. The result hints at a radical new way to understand why the universe keeps speeding up.
• This simple design change could finally fix solid-state batteries
  Scientists in South Korea have discovered a way to make all-solid-state batteries safer and more powerful using inexpensive materials. Instead of adding costly metals, they redesigned the battery’s internal structure to help lithium ions move faster. This simple structural tweak boosted performance by up to four times. The work points to cheaper, safer batteries for phones, electric vehicles, and beyond.