Formation of Structures in the Universe

The lecture explores the formation of large-scale structures in the universe, focusing on galaxy formation theories, including top-down and bottom-up models. It discusses the role of dark matter in the rapid formation of these structures and the evolution of spiral galaxies through mergers. The importance of dark matter in forming clusters and superclusters is emphasized, concluding that dark matter is essential for explaining the universe's structure within 14 billion years.

What is the primary focus of the lecture on the formation of structures in the universe?

• Small-scale structures like planets

• The chemical composition of galaxies

• The distribution of clusters and superclusters

• The formation of individual stars

Which model suggests that smaller galaxies formed first and later merged into larger ones?

• Elliptical model

• Bottom-up model

• Top-down model

• Spiral model

What is a key factor in classifying spiral galaxies?

• The color of the galaxy

• The size of the bulge

• The number of stars

• The presence of black holes

Why is it unlikely for elliptical galaxies to transform into spiral galaxies?

• Spiral galaxies are older

• Elliptical galaxies are too large

• Elliptical galaxies are too far away

• Spiral galaxies have cold gas and dust, which ellipticals lack

What could cause two spiral galaxies to form an elliptical galaxy?

• Gradual cooling

• Increase in star formation

• Loss of dark matter

• A massive collision

Why is ordinary matter alone insufficient to form large-scale structures in the universe?

• It is too dense

• It lacks the necessary time

• It is too scattered

• It is too hot

What role does cold dark matter play in the formation of structures in the universe?

• It helps condense material into structures

• It disperses ordinary matter

• It prevents star formation

• It accelerates the cooling of galaxies

How did the initial universe appear according to the lecture?

• Perfectly smooth

• Almost uniformly spread out

• Filled with large structures

• Highly irregular

What forms the basis of the structure we see in the universe today?

• Ordinary matter

• Galactic winds

• Black holes

• Dark matter

What is still happening in the universe according to the lecture?

• Dark matter is disappearing

• Stars are cooling rapidly

• Ordinary matter is being drawn into filaments

• Galaxies are shrinking