Probing light pseudoscalars with light propagation, resonance and spontaneous polarization

Probing Light Pseudoscalars with Light Propagation, Resonance and Spontaneous Polarization

Radiation propagating over cosmological distances can probe light weakly interacting pseudoscalar (or scalar) particles. The existence of a spin-0 field changes the dynamical symmetries of electrodynamics. It predicts spontaneous generation of polarization of electromagnetic waves due to mode mixing in the presence of background magnetic field. We illustrate this by calculations of propagation ...

Probing Dark Energy with Light: Propagation and Spontaneous Polarization

Radiation propagating over cosmological distances can probe dark energy. The most probable source of dark energy is a spin-0 field which may be a scalar or a pseudoscalar, changing the dynamical symmetries of electrodynamics. Dark energy as a field predicts spontaneous generation of polarization of electromagnetic waves due to mode mixing. We illustrate this by calculations of propagation in a ...

Evading the astrophysical limits on light pseudoscalars

We study the possibility of evading astrophysical bounds on light pseudoscalars by not restricting ourselves to the QCD axion. We argue that the solar bounds can be evaded if we have a sufficiently strong self coupling of the pseudoscalars and their coupling to electrons. The required couplings do not conflict with any known experimental bounds. We also require a small density of pseudoscalar p...

Light Storage with Light of Arbitrary Polarization

New constraints on very light pseudoscalars

There is quite a number of puzzling phenomena in astrophysics that could be clarified with the existence of very light scalar or pseudoscalar particles, commonly refered to as axion-like particles (a.k.a. ALPs). One of the main reasons is that these hypothetical particles can have a coupling to photons inside external magnetic fields, as in the axion case [1], and can lead to observable signatu...