At the end of its lifetime, a star with more than about 20 solar masses can undergo gravitational collapse to form a black hole.

Focusing on the United States, the game describes a country undergoing slow collapse.

The two novels feature common characters in a future where Earth has undergone ecological collapse.

You'd need six or seven billion solar masses undergoing gravitational collapse to release that much energy.

Importantly, this time is a function of the mass/energy of the object undergoing collapse.

Second, East Germany's economy and infrastructure underwent a swift and near-total collapse.

In 1965 I read about Penrose's theorem that any body undergoing gravitational collapse must eventually form a singularity.

The core starts to undergo gravitational collapse.

Recall that neutron stars are incredibly dense, formed when a larger star undergoes gravitational collapse.

The mass above which a cloud will undergo such collapse is called the Jeans mass.