Where Have All the Quasars Gone?

The video explores the nature of supermassive black holes, focusing on their mass, age, and distribution in the universe. It highlights the paradox of younger black holes being more massive, using TON 618 as a case study. The challenges of observing black holes, the role of quasars, and the impact of the universe's expansion on black hole growth are discussed. The video also contrasts elliptical and spiral galaxies in terms of black hole size and star formation.

What is surprising about some of the most massive black holes?

• They are invisible to telescopes.

• They are actually the youngest.

• They are located in the Milky Way.

• They are the oldest in the universe.

How does the mass of TON 618 compare to the Milky Way?

• It is half the size of the Milky Way.

• It is smaller than the Milky Way.

• It is comparable to the Milky Way.

• It is twice the size of the Milky Way.

Why is it challenging to detect black holes?

• They emit too much light.

• They are too small to see.

• They are often surrounded by bright quasars.

• Technology to observe them is still developing.

What is a quasar?

• A type of black hole.

• A small star.

• A type of galaxy.

• A bright object formed by matter falling into a black hole.

What is Mountain Quest bias?

• A theory about the formation of galaxies.

• A bias where brighter objects appear more plentiful at a distance.

• A method for measuring black holes.

• A type of telescope used to observe quasars.

Why are the largest supermassive black holes often found in elliptical galaxies?

• Elliptical galaxies have already lost their gas.

• Elliptical galaxies are closer to us.

• Elliptical galaxies are older.

• Elliptical galaxies have more gas.

What is the Big Freeze theory?

• A theory about the end of the universe where all gas is converted into black holes.

• A theory about the formation of stars.

• A theory about the expansion of the universe.

• A theory about the cooling of galaxies.