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Area of Science:

  • Cosmology
  • Theoretical Physics
  • String Theory

Background:

  • String theories predict numerous axionlike fields with a wide mass range.
  • The
  • Why now?
  • problem questions the recent onset of cosmic accelerated expansion.

Purpose of the Study:

  • To develop a quintessence model based on axionlike fields without super-Planckian excursions.
  • To address the
  • Why now?
  • problem of dark energy domination.
  • To explore observable consequences of this cosmological model.

Main Methods:

  • Utilizing string theory concepts to model axionlike fields.
  • Developing a quintessence model with specific potential modifications.
  • Investigating the probability of dark energy domination onset in cosmic time.

Main Results:

  • A model of quintessence is presented with no super-Planckian field excursions and order-unity dimensionless numbers.
  • The
  • Why now?
  • problem is addressed by a random onset of dark energy domination.
  • A modified axion potential averts the need for rapid decay of unused axion fields.

Conclusions:

  • The proposed scenario can generate a universe like ours with a probability of approximately 1%.
  • The model offers potential observable consequences for future cosmological surveys.
  • This framework provides a novel approach to understanding dark energy and cosmic acceleration.