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Cosmic Microwave Background. Detecting CMB. Approximately 1% of the static noise created by an untuned radio is from the CMB. This is the same for old, untuned television sets.
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Detecting CMB • Approximately 1% of the static noise created by an untuned radio is from the CMB. • This is the same for old, untuned television sets. • The first satellite which captured images of the CMB was COBE. The images it captured however were of a low resolution. The satellite WMAP was later launched and provided much more detailed images of the CMB. A future satellite is planned called the Planck satellite. This is designed with the latest photographic technology to take the most detailed images of the CMB.
Evidence For The Big Bang The temperature in the universe is almost uniform, at only 2 kelvin above absolute zero. This means the universe has cooled evenly, at the same rate. Therefore every part of the universe came into existence at the same time and that the universe originated at a single point, then expanded. This is strong evidence for the theory of the big bang.
Primordial Quantum Fluctuations Inflation is the brief period that occurred less than a second after the Big Bang. It also lasted for just a tiny fraction of a second, yet during this time the Universe grew in size by a factor of . Also during this time, fluctuations in the quantum vacuum appeared, which later resulted in the temperature fluctuations in the CMB that in turn produced large-scale structures such as galaxies. These fluctuations could be caused by the slight uneven mass, or thermal distribution. Physicists currently do not know the answer.
Recombination This was the stage in the early universe when, due to expansion, the universe cooled and meant the protons and electrons became unstable in their unbonded form. The formation of more stable hydrogen then became more energetically favourable. As the universe expanded, the dense cloud of electromagnetic radiation also dispersed over the greater dimensions and the universe changed from opaque, to transparent. At the point of recombination the universe was around 300,000 years old.