Concept explainers
How the Isotropy problem, as depicted in the below figure, was solved using the inflation model.
Answer to Problem 1CC
Solution:
Isotropy exists in the sky because it is believed that during Inflation epoch, which lasted about
Explanation of Solution
Introduction:
Astronomers and Physicists found that the temperature of microwave background in the sky is isotropic. That means if two points are taken, one in east and one in west, then the two points will have the same temperature. This is a problem in the sense that for temperature equality, the two bodies must be in contact with each other or must interact with each other through photons. Since the universe keeps on growing at a rate much greater than the speed of light, photons emitted from one point can’t reach the other point. That means that the points are not interacting with each other neither in terms of photons nor in terms of physical contact. This problem is referred to as Isotropy problem.
Explanation:
It took until the 1980’s to solve the problem of Isotropy in the sky. It was suggested that the universe expanded extremely quickly as about
During this period, the materials that were once together moved far apart rapidly and expanded all across the universe. So the regions that are observed to have same the temperature today were in contact with each in the past and hence they have temperature uniformity though the universe keeps on expanding.
This model is known as Inflationary Model and the behavior of universe in the Inflation epoch successively explains Isotropy problem.
Conclusion:
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Chapter 26 Solutions
Universe
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- The background radiation has an average temperature of 2.7 K, using Wien’s Law, the current background radiation in the microwave region, the peak wavelength is 1mm. In the past, when the cosmic background radiation had a peak wavelength of 51.1 µm, calculate the relative size of the universe compared to the current size of the universe, that is, the universe was how much smaller by a factor of what? Round to TWO places past the decimalarrow_forward1.2 1.0 0.8 0.6 Cosmic background data from COBE 0.4 0.2 0.0 0.5 10 Wavelength A in mm c) Background (CMB) undertaken by the COBE satellite. Use this diagram to estimate the current temperature of the CMB. Based on your estimate, what would the temperature of the CMB have been at a redshift of z = 5000? The left hand diagram above shows the results from observations of the Cosmic Microwave Radiated Intensity per Unit Wavelength (16° Watts/m per mm)arrow_forward
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