In an Imaginary Universe, Astronomers Find That There Are Thousands

question 60

Multiple Choice

In an imaginary universe, astronomers find that there are thousands of galaxies within a few million light-years in all directions, but beyond those galaxies there is nothing but empty space.Such a universe would be

• A) isotropic and homogeneous.
• B) isotropic but not homogenous.
• C) homogeneous but not isotropic.
• D) neither homogeneous nor isotropic.
• E) lacking any evidence for the Big Bang.

---

Definitions:

Infrared Wavelength

Electromagnetic radiation wavelengths longer than visible light but shorter than microwaves, used in heating, remote controls, and night vision.

Wavenumber

A measure of the number of wave cycles per unit of distance, typically used in spectroscopy.

Wavenumber

A measure of the number of wavelengths per unit length, typically used in spectroscopy to denote energy levels.

Wavelength

The distance between successive crests of a wave, typically used in the context of electromagnetic spectrum.