71 citations · 130 across the 16 of their papers we have counts for
18 papers
Carving out the Multifield Cosmological Collider Landscape
Denis Werth
We show that inflation with a large number of fields, as predicted by concrete ultraviolet embeddings, generically produces almost-local cosmological collider signals in the bispec…
Analytic Continuation of Conformal Integrals in Momentum Space
Jonathan Gräfe, Prashanth Raman, Denis Werth
Conformal symmetry strongly constrains correlation functions. In momentum space, the conformal Ward identities are solved for three-point functions by integrals of a product of thr…
All Tree-Level Massive Cosmological Correlators via Spectral Gluing
Jonathan Gräfe, Denis Werth
Massive cosmological correlators exhibit a rich hypergeometric structure already at tree level, reflecting the distorted propagation of particles in de Sitter spacetime. In this pa…
Kontorovich-Lebedev-Fourier Space for de Sitter Correlators
Nathan Belrhali, Arthur Poisson, Sébastien Renaux-Petel +1
In this work, we build a novel frequency-momentum space for -dimensional de Sitter (dS) correlators from first principles. This construction follows directly from the decomp…
Universal Non-Gaussian Signatures from Transient Instabilities
Shuntaro Aoki, Diederik Roest, Denis Werth
We identify universal signatures in the bispectrum arising from a transient tachyonic instability of entropic fluctuations during inflation, a phenomenon that naturally arises in h…
De Sitter Momentum Space
Nathan Belrhali, Arthur Poisson, Sébastien Renaux-Petel +1
We construct a natural and nonperturbative momentum space for quantum field theory on -dimensional de Sitter (dS) spacetime in the Poincaré slicing, adapted to early Univers…
The Exact and Approximate Tales of Boost-Breaking Cosmological Correlators
Zhehan Qin, Sébastien Renaux-Petel, Xi Tong +2
Cosmological correlators offer a remarkable window into the high-energy physics governing Universe's earliest moments, with the tantalising prospect of discovering new particles. H…
Primordial Sharp Features through the Nonlinear Regime of Structure Formation
Clément Stahl, Denis Werth, Vivian Poulin
Sudden violations of the slow-roll regime during inflation, a natural prediction of many UV-complete inflationary models, give rise to sharp features in the primordial power spectr…
Reconstructing Primordial Curvature Perturbations via Scalar-Induced Gravitational Waves with LISA
Jonas El Gammal, Aya Ghaleb, Gabriele Franciolini +17
Many early universe scenarios predict an enhancement of scalar perturbations at scales currently unconstrained by cosmological probes. These perturbations source gravitational wave…
Spectral Representation of Cosmological Correlators
Denis Werth
Cosmological correlation functions are significantly more complex than their flat-space analogues, such as tree-level scattering amplitudes. While these amplitudes have simple anal…
CosmoFlow: Python Package for Cosmological Correlators
Denis Werth, Lucas Pinol, Sébastien Renaux-Petel
Cosmological correlators hold the key to high-energy physics as they probe the earliest moments of our Universe, and conceal hidden mathematical structures. However, even at tree-l…
The Cosmological Flow: A Systematic Approach to Primordial Correlators
Lucas Pinol, Sébastien Renaux-Petel, Denis Werth
The time evolution of primordial fluctuations conceals a wealth of insights into the high-energy physics at play during the earliest moments of our Universe, which is ultimately en…
Parity Violation from Emergent Non-Locality During Inflation
Sadra Jazayeri, Sébastien Renaux-Petel, Xi Tong +2
Parity violation in the early universe holds great promise for uncovering new physics. In particular, the primordial scalar four-point correlation function is allowed to develop a…
Shapes of the Cosmological Low-Speed Collider
Sadra Jazayeri, Sébastien Renaux-Petel, Denis Werth
Massive particles produced during inflation leave specific signatures in soft limits of correlation functions of primordial fluctuations. When the Goldstone boson of broken time tr…
Cosmological Flow of Primordial Correlators
Denis Werth, Lucas Pinol, Sébastien Renaux-Petel
Correlation functions of primordial density fluctuations provide an exciting probe of the physics governing the earliest moments of our Universe. However, the standard approach to…
No-go Theorem for Scalar-Trispectrum-Induced Gravitational Waves
Sebastian Garcia-Saenz, Lucas Pinol, Sébastien Renaux-Petel +1
We show that the contribution of the primordial trispectrum to the energy density of the scalar-induced stochastic gravitational wave background cannot exceed the one from the scal…
Analytical approximations for curved primordial power spectra
Ayngaran Thavanesan, Denis Werth, Will Handley
We extend the work of Contaldi et al. and derive analytical approximations for primordial power spectra arising from models of inflation which include primordial spatial curvature.…
ODEN: A Framework to Solve Ordinary Differential Equations using Artificial Neural Networks
Liam L. H. Lau, Denis Werth
We explore in detail a method to solve ordinary differential equations using feedforward neural networks. We prove a specific loss function, which does not require knowledge of the…