HW 12: The Distribution of Galaxies and The Big Bang

What are the clusters of galaxies found in huge filamentary structures called?

Superclusters

What is the type of matter that comprises most of our universe, does not emit electromagnetic radiation and interact with luminous matter only through gravity called

Dark matter

In the large scale structure, what are the huge empty bubbles walled in by the great arcs of galaxies called?

Voids

What universal law states that the universe is both isotropic and homogeneous?

Cosmological Principle

What is the general relativistic effect that allows us to observe very faint distant galaxies obscured by large galaxy clusters by bending light from distant galaxy sources and producing distorted or multiple images?

Gravitational Lensing

Which project is the largest universe mapping project till date that has confirmed the non-uniform distribution of galaxies in the universe?

SDSS or Sloan Digital Sky Survey

Which supercluster is our Local Group a part of?

Virgo Supercluster

What is the fudge factor introduced by Einstein to explain the universe not gravitationally collapsing and remaining static?

Cosmological constant

What is the moment in time called when the universe was concentrated at a single point, which then exploded to form the seemingly infinite universe we see today?

Big Bang

At what rate is the universe expanding?

Accelerating

The larger the redshift of distant galaxies, the…

farther back in time they are.

What was the peak wavelength of the cosmic microwave background radiation at the time light left the most distant galaxies we can currently see? Assume those galaxies have a cosmological redshift of z = 10. Remember that the redshift is defined as z = (shift in wavelength)/rest wavelength. Also the current temperature of CMB is roughly 2.7 K. Assuming that CMB follows blackbody distribution, you can find the current peak wavelength of the CMB using Wien's law.

11.66 x 10^-3 m