The cosmological tree theorem

SA Salcedo, S Melville - Journal of High Energy Physics, 2023 - Springer
A bstract A number of diagrammatic “cutting rules” have recently been developed for the
wavefunction of the Universe which determines cosmological correlation functions. These …

The open effective field theory of inflation

SA Salcedo, T Colas, E Pajer - Journal of High Energy Physics, 2024 - Springer
A bstract In our quest to understand the generation of cosmological perturbations, we face
two serious obstacles: we do not have direct information about the environment experienced …

Single field inflation in the light of NANOGrav 15-year Data: Quintessential interpretation of blue tilted tensor spectrum through Non-Bunch Davies initial condition

S Choudhury - arxiv preprint arxiv:2307.03249, 2023 - arxiv.org
In this work, we present a quintessential interpretation of having a blue-tilted tensor power
spectrum for canonical single-field slow-roll inflation to explain the recently observed …

A cosmological bootstrap for resonant non-Gaussianity

CD Pueyo, E Pajer - Journal of High Energy Physics, 2024 - Springer
A bstract Recent progress has revealed a number of constraints that cosmological
correlators and the closely related field-theoretic wavefunction must obey as a consequence …

Cosmological correlators through the looking glass: reality, parity, and factorisation

D Stefanyszyn, X Tong, Y Zhu - Journal of High Energy Physics, 2024 - Springer
A bstract 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 …

Differential equations for cosmological correlators

N Arkani-Hamed, D Baumann, A Hillman… - arxiv preprint arxiv …, 2023 - arxiv.org
Cosmological fluctuations retain a memory of the physics that generated them in their spatial
correlations. The strength of correlations varies smoothly as a function of external …

Spinors in (anti-) de Sitter Space

V Schaub - Journal of High Energy Physics, 2023 - Springer
A bstract We explore analytical aspects of correlators involving Dirac spinors in d+ 1-
dimensional de Sitter space. Adapting the formalism of Sleight and Taronna, we show how …

Renormalisation of IR divergences and holography in de Sitter

A Bzowski, P McFadden, K Skenderis - Journal of High Energy Physics, 2024 - Springer
A bstract We formulate a renormalisation procedure for IR divergences of tree-level in-in late-
time de Sitter (dS) correlators. These divergences are due to the infinite volume of spacetime …

In-in formalism for the entropy of quantum fields in curved spacetimes

T Colas, J Grain, G Kaplanek… - Journal of Cosmology and …, 2024 - iopscience.iop.org
We show how to compute the purity and entanglement entropy for quantum fields in a
systematic perturbative expansion. To that end, we generalize the in-in formalism to non …

The discreet charm of the discrete series in dS2

D Anninos, T Anous, B Pethybridge… - Journal of Physics A …, 2023 - iopscience.iop.org
We study quantum field theories placed on a two-dimensional de Sitter spacetime (dS 2)
with an eye on the group-theoretic organization of single and multi-particle states. We …