Related papers: Gravitational Waves from Composite Dark Sectors
It is currently believed that the Standard Model is an effective low energy theory which in principle may contain higher dimensional non-renormalizable operators. These operators may modify the standard model Higgs potential in many ways,…
We present ongoing investigations of the first-order confinement transition of a composite dark matter model, to predict the resulting spectrum of gravitational waves. To avoid long autocorrelations at the first-order transition, we employ…
The evidence of a Stochastic Gravitational Wave Background (SGWB) in the nHz frequency range is posed to open a new window on the Universe. A preferred explanation relies on a supercooled first order phase transition at the 100 MeV - GeV…
We investigate gravitational wave signals in a non-supersymmetric grand unified model where the group $SO(10)$ is broken in two steps to the Standard Model gauge group. We calculate the analytical form of the one-loop effective potential…
We explore the constraints on dark sector models imposed by the recent observation of coincident gravitational waves and gamma rays from a binary neutron star merger, GW170817. Rather than focusing on specific models as has been considered…
We investigate the gravitational wave background from a first order phase transition in a matter-dominated universe, and show that it has a unique feature from which important information about the properties of the phase transition and…
The discovery of gravitational waves opens new opportunities to test BSM physics. In particular, the production of a stochastic background of primordial gravitational waves could provide a signature of the generation of the right-right…
We develop a tool for the analysis of stochastic gravitational wave backgrounds from cosmological first-order phase transitions with LISA: we initiate a template databank for these signals, prototype their searches, and forecast their…
We discuss the gravitational wave spectrum produced by first-order phase transitions seeded by domain wall networks. This setup is important for many two-step phase transitions as seen for example in the singlet extension of the standard…
Motivated by some of the recent swampland conjectures, we study a model of dark energy, in which a quintessence axion slowly rolls in a steep potential due to its interactions with a U(1) or an SU(2) gauge field. The gauge fields produced…
If the cosmological QCD phase transition is strongly first order and lasts sufficiently long, it generates a background of gravitational waves which may be detected via pulsar timing experiments. We estimate the amplitude and the spectral…
We study the production, spectrum and detectability of gravitational waves in models of the early Universe where first order phase transitions occur during inflation. We consider all relevant sources. The self-consistency of the scenario…
Several Pulsar Timing Array (PTA) collaborations have recently provided strong evidence for a nHz Stochastic Gravitational-Wave Background (SGWB). Here we investigate the implications of a first-order phase transition occurring within the…
We compute the gravitational wave spectrum from a dark sector phase transition driven by spontaneous $\ZDW$ breaking. If the transition is second-order, the only source of gravitational waves is the annihilation of domain walls (biased by…
Motivated by the recent evidence of a stochastic gravitational wave background found by pulsar timing array experiments, we focus on one of the prime cosmological explanations, i.e. a supercooled first order phase transition. If confirmed,…
Gravitational-wave tails are due to the backscattering of linear waves onto the space-time curvature generated by the total mass of the matter source. The dominant tails correspond to quadratic non-linear interactions and arise at the…
We have conducted a revised analysis of the first-order phase transition that is associated with symmetry breaking in a classically scale-invariant model that has been extended with a new $SU(2)$ gauge group. By incorporating recent…
The chirality imbalance in QCD is spontaneously induced by a repulsive axial-vector interaction from the instanton anti-instanton pairing at high temperature above the chiral phase transition, and vanishes at low temperature. The chiral…
First-order cosmological phase transitions (PT) can take place in a dark sector at relatively late times between the big-bang nucleosynthesis and recombination epochs. Because bubble nucleation is stochastic, the PT completes at different…
We study a scenario where the Standard Model is extended by a SU(2) gauge group in the dark sector. The three associated dark gauge bosons are stabilised via a custodial symmetry triggered by an additional dark SU(2) scalar doublet, thus…