• gravity waves
• phase transition
• cft
• holography
• cosmology
• astroparticle physics

We model a dark sector as a strongly coupled Conformal Field Theory with deformations that confines at a given scale, creating a mass gap.
The phase transition properties are determined by studying the dual model through the AdS/CFT correspondence.
In this description, AdS space with a black hole corresponds to the deconfined phase of the CFT, whereas a Randall-Sundrum model describes the confined one.
To obtain a detectable signal, and avoid Dark Matter constraints, we consider the scenario of a feeble coupling between the dark sector and the Standard
Model, allowing the energy of the dark sector to be transferred to the visible one. When the decay is slow,
the gravity wave amplitude is reduced, and the frequency is lowered. This opens up parameter space for experiments because strong signals at undetectable frequencies can be shifted inside the experiments' detection range.
We study the parameter space that leads to a gravitational wave background within the projected sensitivity curves
of the future interferometers LISA and Einstein Telescope.
We then consider the signal detected at NANOGrav and IPTA pulsar timing arrays experiments. The main challenge here is to avoid constraints
from Big Bang Nucleosynthesis since frequency suggests a phase transition at a temperature around MeV.
The energy injection mechanism works nicely for IPTA, while for NANOGrav, the signal is more difficult to fit due to tension with Big Bang Nucleosynthesis.