Black Holes Overview

What does the black hole no hair theorem state?

What happens to a star when its core is iron and its mass is less than 1.4 solar masses?

What is the result of a star with a final mass greater than 3 solar masses after a supernova event?

Why does a star between 1.4 and 3 solar masses form into a neutron star rather than a black hole after a supernova?

What is the source of the magnetic fields that produce jets of high-energy particles rushing away from black holes?

How do tidal forces change with the mass and size of a black hole?

How long are quasars typically active for?

What could potentially revive a dead quasar according to the text?

What is the key feature of an area of space-time that defines a black hole?

How is the escape velocity of an object related to its mass and distance from the center of a black hole?

According to Einstein's Theory of General Relativity, what does gravity do to space-time?

What is a key challenge with using 2-dimensional illustrations to represent black holes' warping of nearby space-time?

The no-hair theorem states that a black hole has only three hairs: its mass, electric charge, and angular momentum.

When a star's core is iron and its mass is less than 1.4 solar masses, it collapses and forms a white dwarf.
A star with a final mass greater than 3 solar masses forms a black hole after a supernova event.
A star between 1.4 and 3 solar masses forms a neutron star after a supernova because its gravity is not strong enough to overcome neutron degeneracy pressure.

Magnetic fields around black holes produce jets of high-energy particles.
Tidal forces around a black hole change with the mass and size of the black hole, with stronger forces near smaller black holes.
The escape velocity from a black hole is related to its mass and distance from the center, with more massive black holes having higher escape velocities.

Quasars are typically active for a relatively short period, around 1-10 million years.
A dead quasar can potentially be revived by the merger of two galaxies, which can reignite the flow of gas and dust into the supermassive black hole.

The key feature of an area of space-time that defines a black hole is the event horizon, beyond which nothing, including light, can escape.
According to Einstein's Theory of General Relativity, gravity warps space-time, causing objects to move along curved trajectories.
A key challenge with using 2-dimensional illustrations to represent black holes' warping of nearby space-time is that they cannot accurately depict the complex, three-dimensional curvature of space-time.