230 citations · 3.3k across the 75 of their papers we have counts for
77 papers
The separate universe approach with non minimal coupling to gravity
Hugo Holland, Julien Grain
In this paper we extend a study of the validity conditions of the separate universe approach of cosmological perturbations to models of inflation with multiple fields that are non…
2+1 is not 3: Angular bispectrum and Super-Sample Covariance on the light cone
Fabien Lacasa, Julien Grain
Observations of the Large Scale Structure sit on the light cone. Cosmological statistics must then be projected from 3D to angular space. For the bispectrum and higher orders, the…
Universal CMB Phase Coherence from Single-Field Inflation
Siméon Vareilles, Thomas Colas, Julien Grain +2
The phase coherence of primordial perturbations shapes the acoustic peaks of the CMB and is regarded as a key signature of inflation. Inflationary scenarios at different energy sca…
Explicit gauge-invariant variables in multifield inflation beyond linear order and Hamiltonian dynamics
Julien Grain, Hugo Holland, Lucas Pinol
General relativity coupled to multiple scalar fields is a diffeomorphism-invariant constrained system. Consequently, a naive counting of the perturbative degrees of freedom unavoid…
Large deviations for halos and voids: beyond perturbative non-gaussianities
Martin Teuscher, Ruth Durrer, Julien Grain +2
The excursion-set formalism provides a key connection between primordial density fluctuations and the abundance of cosmic structures such as dark matter halos and voids, traditiona…
Recoherence, adiabaticity, and Markovianity in Gaussian maps
Dimitrios Kranas, Julien Grain, Vincent Vennin
Motivated by the recent discovery of situations where cosmological fluctuations recohere during inflation, we investigate the relationship between quantum recoherence (late-time pu…