FeaturesΒΆ

TransitionListener offers a comprehensive suite of features for simulating and analyzing cosmological first-order phase transitions and their associated gravitational-wave signals. Key features include:

  • Model-independent framework for analyzing first-order phase transitions:

    • Define custom potentials with one or more scalar fields and corresponding particle content.

    • Incorporate thermal corrections to the potential in the 4D approach up to one-loop order including daisy resummation.

    • Accurate counting of relativistic degrees of freedom as a function of temperature.

  • Phase tracing based on CosmoTransitions

    • Adaptive temperature stepping

    • Identification of phase transitions and critical temperatures.

    • Automated tunneling pathfinding using the path deformation method.

    • Computation of bubble profiles and bounce actions.

    • Accuracies adjustable by the user.

  • Bubble nucleation rate calculation and determination of nucleation temperature

    • Also for extremely supercooled transitions and u-shaped bounce actions.

    • Not limited to transitions happening in vacuum domination.

    • Not limited to the Electroweak scale, because the temperature evolution of the Hubble rate is computed self-consistently.

  • State-of-the-art computation of the bubble wall velocity using the local thermal equilibrium approximation, based on the method by van de Vis et al. (2023), https://arxiv.org/pdf/2303.10171.

  • Self-consistent computation of the Hubble rate and the false vacuum fraction

    • During the phase transition, the Hubble rate is computed using the conservation of energy along the bubble wall to compute the reheating temperature.

    • The conservation of entropy in the plasma before and after the transition is used to track the temperature evolution.

  • Computation of the percolation and completion temperatures as well as the reheating temperature:

    • Based on the false vacuum fraction evolution during the transitions

    • Includes the effects of reheating due to latent heat release on the temperature evolution.

    • Heuristic on the transition strength speeds up the computation while maintaining high accuracy up to extreme supercooling.

  • Both the mean bubble separation and the inverse duration of the phase transition are calculated.

    • The numerical results are precise enough to validate analytical relations between them up to the per-cent level.

    • The mean bubble separation is used as the default length scale for gravitational-wave predictions.

  • Prediction of the gravitational-wave spectrum:

    • Contributions from bubble collisions, sound waves and magnetohydrodynamic turbulence in the plasma, including the effects of the lifetime of the sound wave source.

    • State-of-the-art fits to numerical simulations for all contributions.

    • Automatic computation of efficiency factors for the different sources based on the bubble wall velocity and the strength of the phase transition.

  • Observability of the predicted gravitational-wave signal at current and future detectors, including LIGO-VIRGO-KAGRA, LISA, DECIGO, BBO, ET, CE, muAres, and pulsar timing arrays.

  • Pulsar timing array likelihoods based on the Ceffyl code, interfaced through PTArcade, giving access to the NANOGrav 15yr, EPTA, PPTA, and IPTA datasets.

  • Many different scan options:

    • Support for various sampling methods, including grid scans, random scans, line scans, and nested sampling via UltraNest.

    • Flexible configuration through YAML files.

  • Comprehensive plotting utilities for visualizing potentials, tunneling paths, bubble profiles, thermodynamic parameters, and gravitational-wave spectra.

  • Modular and extensible codebase, allowing users to easily add new features or modify existing ones.