The multiverse suggests that our universe may not be unique, but just one of countless others existing beyond our observable reality. Some versions arise naturally from inflation theory and quantum ...

Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to ...

If the universe is 13.8 billion years old, why is the observable universe 46 billion light-years across? This video explains the mind-bending science behind the accelerated expansion of space and why ...