First Star-Forming Structures in Fuzzy Cosmic Filaments.

Area of Science:

• Cosmology
• Astrophysics
• Particle Physics

Background:

• Hierarchical structure formation models posit early galaxies form in low-mass dark matter halos.
• These early galaxies are currently below the detection limits of existing telescopes.
• Future missions will enable observation of these nascent galactic structures.

Purpose of the Study:

• Investigate galaxy assembly within a fuzzy dark matter (FDM) cosmology.
• Explore the impact of ultralight bosonic dark matter on early structure formation.
• Analyze the interplay between baryonic physics and FDM's wave-like properties.

Main Methods:

• Conducted a novel cosmological hydrodynamical simulation.
• Modeled fuzzy dark matter with ultralight bosons (∼10⁻²² eV).
• Examined dark matter filament evolution and baryonic feedback effects.

Main Results:

• FDM filaments exhibited interference patterns and formed soliton-like cores.
• These cores collapsed into kiloparsec-scale spherical solitons under gravity.
• Baryonic feedback minimally affected dark matter distribution features.
• Gas and star distributions showed central cores imprinted by dark matter.

Conclusions:

• FDM cosmology predicts unique dark matter structures (solitons) in early galaxies.
• These dark matter structures leave an observable imprint on gas and star distributions.
• The imprinted cores serve as a potential observational signature for fuzzy dark matter.