English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The inflationary scenario has become the paradigm of early universecosmology, and - in conjuction with ideas from superstring theory - has led tospeculations about an "inflationary multiverse". From a point of view ofphenomenology, the inflationary universe scenario has been very successful.However, the scenario suffers from some conceptual problems, and thus it doesnot (yet) have the status of a solid theory. There are alternative ideas forthe evolution of the very early universe which do not involve inflation butwhich agree with most current cosmological observations as well as inflationdoes. In this lecture I will outline the conceptual problems of inflation andintroduce two alternative pictures - the "matter bounce" and "string gascosmology", the latter being a realization of the "emergent universe" scenariobased on some key principles of superstring theory. I will demonstrate thatthese two alternative pictures lead to the same predictions for the powerspectrum of the observed large-scale structure and for the angular powerspectrum of cosmic microwave background anisotropies as the inflationaryscenario, and I will mention predictions for future observations with which thethree scenarios can be observationally teased apart.

Do we have a Theory of Early Universe Cosmology?