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Perfusion and Inflation of the Mouse Lung for Tumor Histology

Perfusion and Inflation of the Mouse Lung for Tumor Histology

Published on: August 6, 2020

Horizon feedback inflation.

Malcolm Fairbairn¹, Tommi Markkanen², David Rodriguez Roman¹

¹1Department of Physics, King's College London Strand, London, WC2R 2LS UK.

The European Physical Journal. C, Particles and Fields

|April 19, 2019

Summary

This summary is machine-generated.

Gibbons-Hawking radiation influences inflaton dynamics, introducing thermal effects and parameter changes. This leads to a natural hilltop inflation scenario with sufficient expansion and correct perturbations, even with many spectator fields.

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Area of Science:

Cosmology
Theoretical Physics
Quantum Field Theory

Background:

Investigates the impact of quantum effects, specifically Gibbons-Hawking radiation, on the inflaton field during cosmic inflation.
Considers scenarios where the inflaton is coupled to numerous spectator fields, a common feature in many inflationary models.

Purpose of the Study:

To analyze the thermodynamic and energy conservation consequences of Gibbons-Hawking radiation on inflationary potentials and Lagrangian parameters.
To explore a novel hilltop inflation scenario where the inflaton evolves from a trapped state at the origin.

Main Methods:

Applies thermodynamic and energy conservation arguments to derive changes in inflationary parameters due to radiation.
Models a phase transition where the inflaton slowly moves towards its zero-temperature expectation value.

Main Results:

Identifies two key effects: a thermal contribution to the inflaton potential and gradual changes in Lagrangian parameters.
Demonstrates that the proposed hilltop inflation model can achieve sufficient e-folds of expansion and the correct perturbation spectrum.
Shows that this model avoids extreme fine-tuning of potential parameters, provided a large number of spectator fields are present.

Conclusions:

The inclusion of Gibbons-Hawking radiation offers a mechanism for natural initial conditions for inflation.
Hilltop inflation models coupled with spectator fields provide a viable pathway to explaining early universe cosmology without excessive parameter fine-tuning.