Understanding the Universe: Isotropy and Anisotropy

What did Edwin Hubble's observation of red shift in galaxies suggest about the universe?

• The universe is expanding.

• The universe is shrinking.

• The universe is static.

• The universe is contracting.

What does the cosmological principle imply about the universe?

• The universe is shrinking uniformly.

• The universe is isotropic and looks the same in all directions.

• The universe is chaotic and unpredictable.

• The universe is only expanding in one direction.

What evidence supports the idea that the universe is isotropic?

• The uneven distribution of galaxies.

• The irregular shape of the Milky Way.

• The varying brightness of stars.

• The cosmic microwave background.

What did researchers find when they examined X-ray emissions from galaxy clusters?

• Clusters were moving towards the center of the universe.

• Some clusters were brighter or dimmer than expected.

• Clusters were evenly distributed across the sky.

• All clusters were uniformly bright.

What is one possible explanation for the observed anisotropy in the universe?

• Dark energy is decreasing.

• The universe is shrinking.

• Clusters are caught in a 'bulk flow'.

• The Milky Way is expanding.