170 citations · 439 across the 19 of their papers we have counts for
10 papers · 1 filter
Stochastic inflation from a non-equilibrium renormalization group
Sebastián Céspedes, Thomas Colas
Understanding stochastic inflation, and in particular the systematic computation of controlled corrections from first principles, remains an important open problem. In this work, w…
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…
Lectures on Open Effective Field Theories
Thomas Colas
Effective field theories offer a powerful method to unify diverse models under a small set of control parameters, allowing systematic expansions around well-established theories. T…
An Open System Approach to Gravity
Santiago Agüí Salcedo, Thomas Colas, Lennard Dufner +1
Several major open problems in cosmology, including the nature of inflation, dark matter, and dark energy, share a common structure: they involve spacetime-filling media with unkno…
An Open Effective Field Theory for light in a medium
Santiago Agui Salcedo, Thomas Colas, Enrico Pajer
In many scenarios of interest, a quantum system interacts with an unknown environment, necessitating the use of open quantum system methods to capture dissipative effects and envir…
Does decoherence violate decoupling?
C. P. Burgess, Thomas Colas, R. Holman +1
Recent calculations in both flat and de Sitter spacetimes have highlighted a tension between the decoupling of high-energy physics from low-energy degrees of freedom and the expect…
In-in formalism for the entropy of quantum fields in curved spacetimes
Thomas Colas, Julien Grain, Greg Kaplanek +1
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-unitary…
The Open Effective Field Theory of Inflation
Santiago Agui Salcedo, Thomas Colas, Enrico Pajer
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 by primo…
Decoherence out of fire: Purity loss in expanding and contracting universes
Thomas Colas, Claudia de Rham, Greg Kaplanek
We investigate quantum decoherence in a class of models which interpolates between expanding (inflation) and contracting (ekpyrosis) scenarios. For the cases which result in a scal…
Benchmarking the cosmological master equations
Thomas Colas, Julien Grain, Vincent Vennin
Master equations are commonly employed in cosmology to model the effect of additional degrees of freedom, treated as an "environment", onto a given "system". However, they rely on…