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INFLATION

It is not easy to find a theory for the dynamics of the universe that is in agreement with our observations. One of the biggest challenges is to explain why matter in the universe is spread out so evenly and similarly in all directions. The currently most widely accepted explanation for this observation is that the universe underwent a very rapid phase of expansion before matter had cooled enough for atomic nuclei to form. This phase of expansion has been called "inflation" and has been successful also to explain other observations, such as the typical sizes of structures that we see in the universe.

Inflation also predicts the generation of small ripples in space that originate from quantum fluctuations in the very early universe and that later, after the universe has cooled down, leave marks in the cosmic microwave background radiation. However, there isn't presently one model of inflation, but several. To really understand what happened in the early universe we have to find a way to distinguish which model is correct. This can only be done by working out the predictions of these models and by contrasting them with data.

A specific aspect of inflation that is currently investigated at Nordita is the origin of cosmic magnetic fields. Another research project is dedicated to studying how to distinguish whether the universe started in a big bang, or if it previously went through a phase of contraction followed by a big bounce into the present phase of expansion.


This page was printed on 2024-03-29 from www.nordita.org/research/he/inf