Pro ISSI talk

Abstract: The idea of where and how humanity fits into its surroundings has shaped ideas for centuries. The image of the universe around us has changed dramatically in the past 100 years. The immensity of the universe and the fact that it is dynamic and not static have been recognized early in the 20th century and with the close of the last millennium a new and possibly dominating component has been discovered. The current cosmological model is based on gravity and hence Einstein’s General Relativity. As simplifications homogeneity and isotropy are introduced to make the models manageable. These can be tested and appear to be acceptable assumption. With such an underlying theory the observations currently require four major components: radiation, matter, dark matter and dark energy. The observational status includes knowledge about the state of the universe about 3 minutes and 300,000 years after the Big Bang and then the evolution to the variety of galaxies, stars and planets, we observe today. The talk will give an overview of the current understanding of cosmology and the observations on which it is based.