Zobrazeno 1 - 10
of 721
pro vyhledávání: '"Vennin, P"'
Autor:
Jackson, Joseph H. P., Assadullahi, Hooshyar, Gow, Andrew D., Koyama, Kazuya, Vennin, Vincent, Wands, David
We simulate the distribution of very rare, large excursions in the primordial density field produced in models of inflation in the very early universe which include a strong enhancement of the power spectrum. The stochastic $\delta \mathcal{N}$ forma
Externí odkaz:
http://arxiv.org/abs/2410.13683
Publikováno v:
JCAP 08 (2024) 047
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 dynamics (i.e. accounting for the presence of an environment) and to t
Externí odkaz:
http://arxiv.org/abs/2406.17856
Publikováno v:
EPL 148, 29002 (2024)
We show that the simplest, and currently favoured, theoretical realizations of cosmic inflation yield a sharp prediction for the running of the spectral index $\alpha_\mathrm{S}$. Using latest cosmological data, we compute its marginalized posterior
Externí odkaz:
http://arxiv.org/abs/2404.15089
Publikováno v:
JCAP2407:087,2024
The capability of Cosmic Inflation to explain the latest Cosmic Microwave Background and Baryonic Acoustic Oscillation data is assessed by performing Bayesian model comparison within the landscape of nearly three-hundred models of single-field slow-r
Externí odkaz:
http://arxiv.org/abs/2404.10647
Publikováno v:
JCAP 08 (2024) 042
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 their standard adiabatic vacuum. The process is very efficient in de Sitte
Externí odkaz:
http://arxiv.org/abs/2403.12240
Autor:
Vennin, Vincent, Wands, David
Quantum diffusion describes the inflow of vacuum quantum fluctuations as they get amplified by gravitational instability, and stretched to large distances during inflation. In this picture, the dynamics of the universe's expansion becomes stochastic,
Externí odkaz:
http://arxiv.org/abs/2402.12672
Autor:
Animali, Chiara, Vennin, Vincent
Publikováno v:
JCAP08(2024)026
We study how large fluctuations are spatially correlated in the presence of quantum diffusion during inflation. This is done by computing real-space correlation functions in the stochastic-$\delta N$ formalism. We first derive an exact description of
Externí odkaz:
http://arxiv.org/abs/2402.08642
If dark matter is made of QCD axions, its abundance is determined by the vacuum expectation value acquired by the axion field during inflation. The axion is usually assumed to follow the equilibrium distribution arising from quantum diffusion during
Externí odkaz:
http://arxiv.org/abs/2312.08231
Autor:
Jackson, Joseph H. P., Assadullahi, Hooshyar, Gow, Andrew D., Koyama, Kazuya, Vennin, Vincent, Wands, David
The separate-universe approach gives an intuitive way to understand the evolution of cosmological perturbations in the long-wavelength limit. It uses solutions of the spatially-homogeneous equations of motion to model the evolution of the inhomogeneo
Externí odkaz:
http://arxiv.org/abs/2311.03281
Autor:
Bagui, Eleni, Clesse, Sebastien, De Luca, Valerio, Ezquiaga, Jose María, Franciolini, Gabriele, García-Bellido, Juan, Joana, Cristian, Jain, Rajeev Kumar, Kuroyanagi, Sachiko, Musco, Ilia, Papanikolaou, Theodoros, Raccanelli, Alvise, Renaux-Petel, Sébastien, Riotto, Antonio, Morales, Ester Ruiz, Scalisi, Marco, Sergijenko, Olga, Unal, Caner, Vennin, Vincent, Wands, David
In the recent years, primordial black holes (PBHs) have emerged as one of the most interesting and hotly debated topics in cosmology. Among other possibilities, PBHs could explain both some of the signals from binary black hole mergers observed in gr
Externí odkaz:
http://arxiv.org/abs/2310.19857