170 citations · 439 across the 19 of their papers we have counts for
19 papers
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…
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…
Primordial non-Gaussianity constraints on dissipative inflation
Santiago Agüí Salcedo, Thomas Colas, Petar Suman +3
Dissipative effects appear in many early-Universe scenarios, yet their universal observational signatures and systematic confrontation with data remain largely unexplored. We emplo…
Phenomenology of an Open Effective Field Theory of Dark Energy
Santiago Agüí Salcedo, Thomas Colas, Lennard Dufner +1
All observational evidence for dark matter and dark energy is so far exclusively gravitational. Hence, the dark sector may be equivalently described by a theory of the spacetime me…
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…
Quantum estimation of cosmological parameters
Michał Piotrak, Thomas Colas, Ana Alonso-Serrano +1
Understanding how well future cosmological experiments can reconstruct the mechanism that generated primordial inhomogeneities is key to assessing the extent to which cosmology can…
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…
Open Effective Field Theories for cosmology
Thomas Colas
When energy is not conserved, imprints of new physics on observable cosmology might not follow the rules of local effective actions. By capturing dissipative and diffusive effects,…
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…
Cosmic Purity Lost: Perturbative and Resummed Late-Time Inflationary Decoherence
C. P. Burgess, Thomas Colas, R. Holman +2
We compute the rate with which unobserved fields decohere other fields to which they couple, both in flat space and in de Sitter space, for spectator scalar fields prepared in thei…
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…
Quantum recoherence in the early universe
Thomas Colas, Julien Grain, Vincent Vennin
Despite being created through a fundamentally quantum-mechanical process, cosmological structures have not yet revealed any sign of genuine quantum correlations. Among the obstruct…
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…
Four-mode squeezed states: two-field quantum systems and the symplectic group
Thomas Colas, Julien Grain, Vincent Vennin
We construct the four-mode squeezed states and study their physical properties. These states describe two linearly-coupled quantum scalar fields, which makes them physically releva…
Efficient Cosmological Analysis of the SDSS/BOSS data from the Effective Field Theory of Large-Scale Structure
Thomas Colas, Guido D'Amico, Leonardo Senatore +2
The precision of the cosmological data allows us to accurately approximate the predictions for cosmological observables by Taylor expanding up to a low order the dependence on the…