Jingszo !

For decades, cosmologists have worked under the inflationary paradigm, a model that suggests that the universe expanded extremely rapidly, in a fraction of a second, thus paving the way for everything we observe today. But this model includes too many adjustable parameters—the free parameters—which can be modified. Scientifically, this poses a problem, as it makes it difficult to know whether a model is truly predicting or simply adapting to the data.

In a significant breakthrough, the team has proposed a model in which the early universe does not require any of these arbitrary parameters. Instead, it begins with a well-established cosmic state called De Sitter space, which is consistent with current observations of dark energy.

Paper:

Inflation without an inflaton

https://journals.aps.org/prresearch/abstract/10.1103/vfny-pgc2