For more than a century, modern physics has rested on two towering frameworks that do not quite agree with each other.

Physicists are quietly testing wild new theories that treat a hidden fifth dimension as more than science fiction, suggesting ...

We experience the flow of time because it’s a natural outcome of the basic laws of physics. But we may need to build a whole new model to account for gravity’s influence.

Like stretch marks left on skin that expanded too quickly or cracks embedded in freezing ice, cosmic strings are artifacts of ...