38 citations · 40 across the 7 of their papers we have counts for
8 papers · 1 filter
All-Loop Renormalization and the Phase of the de Sitter Wavefunction
Alexander Farren, Ciaran McCulloch, Enrico Pajer +1
Cosmological observables of the primordial universe are encoded in the late-time field-theoretic wavefunction. For shift-symmetric scalars in de Sitter, a good approximation for ma…
Open Effective Field Theory and the Physics of Cosmological Collider Signals
Thomas Colas, Zhehan Qin, Xi Tong
We examine the origin of the cosmological collider signal using the framework of open effective field theories. Focusing on the single exchange of a massive scalar field, we demons…
Every Wrinkle Carries A Memory: An Integro-differential Bootstrap for Features in Cosmological Correlators
Sadra Jazayeri, Xi Tong, Yuhang Zhu
Motivated by cosmological observations, we push the cosmological bootstrap program beyond the de Sitter invariance lamppost by considering correlators that explicitly break scale i…
Unitary and Analytic Renormalisation of Cosmological Correlators
Diksha Jain, Enrico Pajer, Xi Tong
Loop contributions to cosmological correlators and to the associated wavefunction are of key theoretical and phenomenological interest. Here, we investigate and compare different r…
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…
A Match Made in Heaven: Linking Observables in Inflationary Cosmology
David Stefanyszyn, Xi Tong, Yuhang Zhu
Cosmological correlation functions of inflaton and graviton perturbations are the fundamental observables of early universe cosmology and remain a primary target for observations.…
A Cosmological Tachyon Collider: Enhancing the Long-Short Scale Coupling
Ciaran McCulloch, Enrico Pajer, Xi Tong
The squeezed limit of the primordial curvature bispectrum is an extremely sensitive probe of new physics and encodes information about additional fields active during inflation suc…
Cosmological Correlators Through the Looking Glass: Reality, Parity, and Factorisation
David Stefanyszyn, Xi Tong, Yuhang Zhu
We consider the evolution of quantum fields during inflation, and show that the total-energy singularities appearing in the perturbative expansion of the late-time Wavefunction of…