Higgs-induced screening mechanisms in scalar-tensor theories

Area of Science:

• Theoretical physics
• Particle physics
• Cosmology

Background:

• Conformally coupled scalar fields interact with spacetime curvature.
• Standard Model Higgs-portal couplings link the Higgs boson to other scalar fields.
• Environmental effects can influence fundamental particle properties.

Purpose of the Study:

• To investigate the behavior of a light conformally coupled scalar field.
• To explore its equivalence to Standard Model Higgs-portal couplings.
• To understand how environmental energy density impacts its properties and screening mechanisms.

Main Methods:

• Analyzing a scalar field theory with linear and quadratic terms in the conformal coupling function.
• Expanding the classical potential around its minimum.
• Investigating the effective mass and couplings of the light propagating mode.

Main Results:

• The effective mass and matter couplings of the light scalar mode depend on the background energy density.
• Nonlinearities from the Higgs potential are transferred to the light scalar mode.
• A novel screening mechanism is demonstrated where light degrees of freedom evade experimental constraints.

Conclusions:

• Environmental effects can induce nonlinearities in scalar field theories.
• This work presents a new realization of screening mechanisms for light scalar fields.
• The findings have implications for understanding fundamental physics in varying cosmological environments.