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windy miller
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I have heard that results form CMB experiments show a suppression of power at large angular scales. Can someone explain what "suppression of power" means in laymen terms in this context?
Any reference maybe ?windy miller said:I have heard that results form CMB experiments show a suppression of power at large angular scales. Can someone explain what "suppression of power" means in laymen terms in this context?
here for example https://arxiv.org/abs/1904.07249Arman777 said:Any reference maybe ?
It means that there is less variance in temperature from place to place on the sky at those scales than expected. I'm not sure there is sufficient that this is a real effect and not just a statistical anomaly.windy miller said:I have heard that results form CMB experiments show a suppression of power at large angular scales. Can someone explain what "suppression of power" means in laymen terms in this context?
Power suppression in the CMB (cosmic microwave background) refers to the decrease in the amplitude of the temperature fluctuations in the CMB at small angular scales. This phenomenon is observed in the power spectrum of the CMB, which shows the distribution of temperature fluctuations across different angular scales.
The primary cause of power suppression in the CMB is the process of photon diffusion. In the early universe, photons were tightly coupled to baryonic matter and could not travel freely. As the universe expanded and cooled, the photons decoupled from the matter and began to travel freely. This diffusion process smooths out the temperature fluctuations at small scales, leading to power suppression in the CMB.
Power suppression in the CMB provides important clues about the composition and evolution of the universe. The amplitude of the temperature fluctuations at small scales is affected by the amount of dark matter and dark energy in the universe, as well as by the expansion rate of the universe. Therefore, studying power suppression in the CMB can help us better understand the structure and dynamics of the universe.
Yes, power suppression in the CMB is an important tool for testing and constraining different cosmological models. By comparing the observed power spectrum of the CMB with the predictions of different models, scientists can determine which model best fits the data and provides the most accurate description of the universe.
Power suppression in the CMB is measured using instruments such as the Planck satellite and ground-based telescopes. These instruments map the CMB across the sky and measure the temperature fluctuations at different angular scales. The power spectrum is then calculated from these measurements, and the degree of power suppression can be determined by comparing it to theoretical predictions.