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Non-gaussianities in the observable universe and the origin of cosmic inhomogeneities


Inflation provides a natural mechanism to account for the origin of cosmic structures. The generation of primordial inhomogeneities during inflation is usually computed as the result of the (gravitationally-induced) spontaneous creation of quanta from an initial vacuum state. However, as recently pointed out by Agullo and Parker, when the corresponding stimulated creation is considered, the characteristics of the state of the universe at the onset of inflation are not diluted by the inflationary expansion and can be imprinted in the distribution of primordial inhomogeneities. The objective of this research project is to provide a detailed analysis of the consequences of the stimulated creation effect during inflation.

We will analyze the consequences of having a totally arbitrary initial state describing metric perturbations at the onset of inflation for the predictions of inflation regarding the Cosmic Microwave Background (CBM) anisotropies and galaxy distribution. We will pay special attention to the effects concerning non-gaussianites. This analysis will provide a characterization of the pattern expected from a generic non-vacuum state and, on the other hand, will show what information about that state can be extracted from observations.

On the other hand, the stimulated creation effect opens a window towards the observation of pre-inflationary effects in the CMB and galaxy distribution. The objective of this part of the research project is to work out in detail the predictions arising from quantum gravity proposals of the early universe, and the potential that forthcoming observations have to constrain those proposals.

Call for proposal

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Trinity Lane The Old Schools
CB2 1TN Cambridge
United Kingdom

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Activity type
Higher or Secondary Education Establishments
Administrative Contact
Renata Schaeffer (Ms.)
EU contribution
€ 209 033,40