Bekir Can Lütfüoğlu

Drop a pebble into a well, and the sound tells you its depth. That's roughly how astrophysicists listen to black holes: after a merger or other disturbance, the hole vibrates, emitting gravitational waves. The frequency and damping of this 'ring' depend on what's inside the hole.

A black hole is like a pot that slowly boils away. Its surface emits particles, a process known as Hawking radiation. The hotter the pot, the faster it empties. But what if the pot is not ordinary, but has a double bottom — capable of turning into a passage to another place?