which evidence supports the idea that cosmic microwave radiation is a remnant of the big bang?
a) its temperature is uniform
b) its mass fluctuates greatly
c) its temperature fluctuates greatly
d) its mass is uniform
a) its temperature is uniform
The evidence that supports the idea that cosmic microwave radiation is a remnant of the Big Bang is option "a) its temperature is uniform."
The discovery of the cosmic microwave background (CMB) radiation in 1964 by Arno Penzias and Robert Wilson provided strong evidence for the Big Bang theory. The CMB radiation is a faint glow of microwave radiation that permeates the entire universe and is detected in every direction.
The uniform temperature of the CMB is an essential characteristic that supports the Big Bang theory. The Big Bang theory predicts that the universe originally expanded from an extremely hot and dense state. As the universe expanded, it also cooled down. The uniform temperature of the CMB radiation, currently measured at about 2.7 Kelvin (-270.45 degrees Celsius or -454.81 degrees Fahrenheit), suggests that the universe was once in thermal equilibrium. If the temperature were fluctuating greatly, it would indicate that the universe had not reached thermal equilibrium and would challenge the Big Bang theory.
The correct answer is option a) its temperature is uniform.
To understand why the temperature of cosmic microwave radiation supports the idea that it is a remnant of the Big Bang, we need to explore the concept of the Big Bang and the subsequent formation of cosmic microwave background radiation.
The Big Bang theory is the prevailing scientific explanation for the origin of the universe. According to this theory, the universe originated from a high-density, high-temperature state around 13.8 billion years ago. As the universe rapidly expanded, it underwent a cooling process, eventually leading to the formation of atoms.
During this cooling process, radiation was released, which is known as cosmic microwave background radiation (CMB). This radiation is essentially leftover energy from the hot and dense early universe. As the universe expanded and cooled down further, this radiation steadily cooled as well.
Now, coming back to the evidence, the uniform temperature of the cosmic microwave background radiation is a strong supporting piece of evidence for the Big Bang theory. Scientists have measured the temperature of this radiation to be approximately 2.7 Kelvin (-270.45 degrees Celsius or -454.81 degrees Fahrenheit) across the entire observable universe.
The uniformity of the CMB temperature is significant because it suggests that it originated from an era when the entire universe had an almost identical temperature. This uniformity can be explained by the rapid expansion of space during the early moments of the Big Bang. As space expanded, any temperature variations that might have existed in the early universe got stretched out over a vast region, resulting in an almost uniform temperature observed today.
On the other hand, options b) and c) are incorrect since they mention fluctuations in mass and temperature. While the mass of cosmic microwave radiation is not applicable, its temperature fluctuations are not significant. The CMB temperature fluctuations are minor and were caused by slight density variations in the early universe, which eventually led to the formation of galaxies and galaxy clusters.
Therefore, the uniform temperature of cosmic microwave radiation is the crucial piece of evidence that supports the idea of it being a remnant of the Big Bang.