Why is the universe flat?

The video explores two major cosmological problems: the horizon and flatness problems, which challenge the conventional Big Bang Theory. It introduces the theory of cosmic inflation proposed by Alan Guth in the 1980s, which offers solutions to these problems. Inflation theory suggests that the universe underwent rapid expansion, allowing for uniform temperature and density. The video explains how inflation forces the universe toward critical density, solving the flatness problem. Despite its revolutionary nature, inflation theory remains a topic of debate, requiring further observational evidence to support or refine it.

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