Inflatable Dark Matter

Area of Science:

• Cosmology
• Particle Physics
• Astrophysics

Background:

• Many new physics models predict overproduction of dark matter.
• Existing dark matter candidates face constraints from overproduction or require fine-tuning.

Purpose of the Study:

• To introduce and explore the
• inflatable dark matter
• scenario.
• To demonstrate how late-time inflation can resolve dark matter overproduction problems.
• To show the broad applicability of this scenario to various dark matter candidates.

Main Methods:

• Theoretical modeling of dark matter density evolution.
• Analysis of particle physics models with a late-time inflationary phase.
• Investigation of thermal relic and nonthermal axion abundance within the scenario.

Main Results:

• A short period of late-time inflation can significantly reduce dark matter particle density.
• The scenario elegantly resolves the overproduction problem for thermal relics.
• It accommodates both very heavy and very light dark matter candidates.
• Nonthermal abundances of grand unified theory or Planck scale axions can be controlled without anthropic tuning.

Conclusions:

• The inflatable dark matter scenario provides a unified solution to dark matter overproduction.
• It broadens the parameter space for viable dark matter candidates and axion physics.
• Late-time inflation, potentially triggered by hidden sector physics, offers a flexible cosmological mechanism.