Very happy to see my new paper with Miguel Sabogal and Eleonora Di Valentino appear on arXiv today! There have been hundreds of papers over the past decade studying interacting dark energy (IDE) models and testing these against cosmological observations, especially in light of cosmological tensions. However, we felt none of these papers really addressed a key question: what are the genuine signatures of IDE which are being constrained by these observations? This is a surprisingly non-trivial question to answer, and our paper does exactly so, by doing a series of controlled comparisons (for which we used the metaphor of peeling an onion as in our Fig. 1) where we gradually remove scale shifts and background effects, until we reach genuine cosmological signatures of IDE. You can read the results in the preprint we just posted on arXiv: 2609.18288.
Pietro Fracca's BSc defense
Congratulations to Pietro Fracca, who today successfully defended his BSc thesis, by the title of “A beginner’s introduction to the ΛCDM cosmological model” (with the opponent being Prof. Valter Moretti)! In his thesis which I supervised, Pietro reviewed and showed the effects of the 6 ΛCDM cosmological parameters on the main cosmological observables (CMB and matter power spectrum), a work far from trivial for a BSc student.
