Legend has it that Isaac Newton had the moment of inspiration that would lead to his theory of gravity when, on a warm afternoon, he saw an apple fall from a tree and wondered why it should fall down ...

Every time a coffee mug drops, a satellite orbits or an astronaut floats, we are watching the same phenomenon play out under very different disguises. For centuries we have treated gravity as the ...

You jump up, and gravity brings you back down to Earth. You reach the brow of a hill and gravity accelerates you down the other side. All neat and tidy then: gravity behaves in the way Newton thought ...

Add Yahoo as a preferred source to see more of our stories on Google. An illustration shows matter rushing forward from a singularity at the dawn of time during the Big Bang. | Credit: Robert Lea ...

Emergent gravity is a bold idea. It claims that the force of gravity is a mere illusion, more akin to friction or heat—a property that emerges from some deeper physical interaction. This emergent ...

What is space-time? Depending on how fast you're moving or how close you are to Earth's gravity can change the way time feels. Einstein’s theory of general relativity views time similarly to width, ...

The holy grail of theoretical physics is to come up with a quantum theory of gravity. But after a century of trying we really have no idea how close we are, or it it's even possible. But we shouldn't ...