Question

In a figure showing Cosmic Microwave Background radiation, which shows how the spectrum of the CMB will look in 5 billion years?

a) A curve shifting to lower temperatures
b) A curve shifting to higher temperatures
c) A straight horizontal line
d) A parabolic curve

Answer 1

The spectrum of the CMB in 5 billion years will look like a curve shifting to lower temperatures due to the continuous expansion of the universe and the consequent redshirting of light.

Step-by-step explanation:

In the context of the Cosmic Microwave Background radiation (CMB), the question asks which description best fits how the spectrum of the CMB will look in 5 billion years. The correct answer is a) A curve shifting to lower temperatures. The CMB is evidence of the early universe and is a nearly perfect blackbody radiation curve. As the universe expands over time, the temperature associated with the CMB will decrease, leading to a redshift in the radiation spectrum. This means that the peak of the CMB spectrum will move to longer wavelengths which are associated with lower temperatures.