Question

The cosmic microwave background

a. is a blackbody spectrum
b. shows the motion of the earth and the Galaxy through the universe c. shows evidence quantum fluctuations from the early universe
d. has a temperature of about 3 degrees Kelvin
e. all of the above
f. none of the above

Answer 1

The cosmic microwave background is a blackbody spectrum with a temperature around 2.725 Kelvin, showing fluctuations that indicate quantum events from the early universe and contributing to understanding cosmic structure.

Step-by-step explanation:

The cosmic microwave background (CMB) is a crucial piece of evidence for the Big Bang theory, yielding insights about the early universe. Indeed, the CMB is a blackbody spectrum, the most precise one known, and it indicates the residual heat from the Big Bang, now cooled to an average temperature of about 2.725 Kelvin. This radiation, detectable from all directions in space, also contains minor fluctuations which are interpreted as marking the quantum fluctuations of the early universe, and consequently, evidence for the structure and composition of the cosmos, including dark matter and dark energy. The discovery of the CMB was a pivotal moment in the field of physics, with Penzias and Wilson being awarded the Nobel Prize for their work.