Why in News? 

• Researchers have successfully created the first laboratory analog of the "black hole bomb," a concept initially proposed by physicist Yakov Zel’dovich in 1971.  

About Black Hole Bomb 

• Concept: The black hole bomb concept utilizes the rotational energy of a spinning black hole’s ergosphere (the region just outside the event horizon). In this area, the intense rotation amplifies nearby particles, leading to significant energy release. 
• Process: Zel'dovich envisioned a fast-spinning cylinder that, when hit by waves, would make them stronger as they bounced back. This process demonstrates the idea of energy amplification using rotational dynamics. 
• Zel’dovich Effect: The phenomenon observed, known as the Zel’dovich effect, occurs when a spinning object moves faster than incoming waves, causing a shift in the waves similar to the Doppler effect. However, unlike the Doppler effect, this shift is due to the rotation of the object rather than its motion through space.