*Article* **Primordial Power Spectra from an Emergent Universe: Basic Results and Clarifications**

### **Killian Martineau and Aurélien Barrau \***

Laboratoire de Physique Subatomique et de Cosmologie, Université Grenoble-Alpes, CNRS/IN2P3 53, avenue des Martyrs, 38026 Grenoble CEDEX, France; killian.martineau@gmail.com

**\*** Correspondence: barrau@in2p3.fr

Received: 30 November 2018; Accepted: 15 December 2018; Published: 18 December 2018

**Abstract:** Emergent cosmological models, together with the Big Bang and bouncing scenarios, are among the possible descriptions of the early Universe. This work aims at clarifying some general features of the primordial tensor power spectrum in this specific framework. In particular, some naive beliefs are corrected. Using a toy model, we investigate the conditions required to produce a scale-invariant spectrum and show to what extent this spectrum can exhibit local features sensitive to the details of the scale factor evolution near the transition time.

**Keywords:** Emergent universe; quantum cosmology; primordial tensor spectrum
