Cosmic microwave background

In this episode, we explore the cosmic microwave background (CMB), often referred to as the 'afterglow' of the Big Bang. This faint radiation permeates the universe and provides a snapshot of its state nearly 380,000 years after the Big Bang. We'll discuss its discovery, what it tells us about the early universe, and how it supports the Big Bang theory. Building on previous discussions of cosmology, dark matter, and dark energy, this episode delves into how the CMB serves as a cornerstone of modern astrophysics, offering insights into the universe's origin, composition, and evolution.

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What is the cosmic microwave background (CMB)?

  1. Radiation left over from the Big Bang.
  2. The light emitted by galaxies.
  3. Thermal radiation from stars.
  4. A snapshot of the universe ~380,000 years after the Big Bang.
  5. The glow of dark matter.

What is the average temperature of the CMB?

  1. 300 K.
  2. 2.725 K.
  3. 0 K.
  4. 1000 K.
  5. 10 K.

What does the CMB tell us about the universe?

  1. The universe is flat in geometry.
  2. The proportions of dark matter, dark energy, and ordinary matter.
  3. The age of the universe is infinite.
  4. The rate of cosmic expansion in the early universe.
  5. The exact nature of black holes.

Who discovered the CMB?

  1. Albert Einstein.
  2. Arno Penzias and Robert Wilson.
  3. Edwin Hubble.
  4. Ralph Alpher and Robert Herman.
  5. George Gamow.

What role do anisotropies in the CMB play?

  1. They indicate quantum fluctuations in the early universe.
  2. They are the seeds of galaxies and large-scale structures.
  3. They show that the universe is not expanding.
  4. They represent cold spots of dark matter.
  5. They confirm the existence of the Higgs boson.

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