A new mathematical breakthrough sheds light on how tiny black holes could emerge from critical states of spacetime. Black holes are often portrayed as cosmic giants, swallowing stars and shaping entire galaxies. But some of the most intriguing black holes predicted by physics could be far smaller than an atom. For decades, scientists have known [...]

Kinematics: The Velocity-Time Function Author’s Preface: A Collaborative Approach to Lesson Development The intention behind what I hope will be a series of articles on Kinematics (this one being the first) is to begin an open, collaborative process of lesson development on Physics Forums. In order to expedite this workflow, I am making deliberate use...

Direct answer: Cosmologists classify the universe as open, flat, or closed based on spatial curvature. Current cosmic microwave background (CMB) measurements indicate the universe is very close to flat, but small curvature remains observationally allowed. Whether the universe is ultimately finite or infinite cannot be settled by theory alone, since all three curvature types are...