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Linné on line arrow Physics and the Cosmos arrow Macrocosmos arrow Big Bang arrow Formation of galaxies in the Big Bang

Formation of galaxies in the Big Bang

Since nearly all matter is in the form of electrically neutral atoms at this point, they no longer interact electromagnetically. Therefore, gravitation is the dominating interaction.

Can this weak interaction be the origin of amplifying inhomogeneities (irregularities) on the atomic level and give rise to galaxies? The answer is yes, and this model is the part of the Big Bang-model, which describes the formation of galaxies.

The idea behind the model is that small inhomogeneities in the atomic gas will be amplified by the influence of gravitation forming gas clouds. Within the gas clouds the inhomogeneities are amplified even more and early stages of stars are formed. If the amount of gas is sufficient the density will become so high that hydrogen atoms are fused into helium – a star is born. The formation of new stars is an ongoing process in existing galaxies.

Since elements heavier than iron cannot be created by spontaneous fusion in stars, the Universe we know today has not been formed by these processes alone. On earth, for example, we have heavier elements than iron. How were these elements created? Well ...