相关论文: Gravitational Wave Probe of Gravitational Dark Mat…

In many models of inflation, the period of accelerated expansion ends with preheating, a highly non-thermal phase of evolution during which the inflaton pumps energy into a specific set of momentum modes of field(s) to which it is coupled.…

We describe the challenges and pathways when probing inflaton as dark matter with the stochastic gravitational waves (GWs) signal generated during the (p)reheating. Such scenarios are of utmost interest when no other interaction between the…

Inflation with Weyl scaling symmetry provides a viable scenario that can generate both the nearly scaling invariant primordial density fluctuation and a dark matter candidate. Here we point out that, in additional to the primordial…

We study gravitational wave production during kinetic preheating after inflation with a focus on scenarios that arise in $\alpha$-attractor models where a scalar dilaton-like inflaton is kinetically coupled to a second scalar field. We…

We study gravitational wave production in an expanding Universe during the first stages following inflation, and investigate the consequences of the Gauss-Bonnet term on the inflationary parameters for a power-law inflation model with a GB…

Gravitational waves signatures from dynamical scalar field configurations provide a compelling observational window on the early universe. Here we identify intriguing connections between dark matter and scalars fields that emit…

Stochastic gravitational wave backgrounds (SGWBs) receive increasing attention and provide a new possibility to directly probe the early Universe. In the preheating process at the end of inflation, parametric resonance can generate large…

We investigate a novel gravitational wave (GW) production mechanism from gravitons generated during the pre-thermal phase of cosmic reheating, where the energy density is dominated by non-thermalized inflaton decay products, dubbed…

Preheating after inflation involves large, time-dependent field inhomogeneities, which act as a classical source of gravitational radiation. The resulting spectrum might be probed by direct detection experiments if inflation occurs at a low…

We calculate the gravitational waves (GWs) produced by primordial black holes (PBHs) in the presence of the inflaton condensate in the early Universe. Combining the GW production from the evaporation process, the gravitational scattering of…

The evidence for the existence of dark matter (DM) is compelling, yet its nature remains elusive. A minimal scenario involves DM interacting solely through gravity. However, the detection would be extremely challenging. In the early…

We propose a gauge singlet scalar with mass around 1-100 TeV as a thermal heavy dark matter candidate along with a dilaton as a Higgs portal mediator in a dimensionless scalar extension of the Standard Model. We demonstrate analytically…

After inflation, a period of preheating may have produced a stochastic background of high frequency gravitational waves (GWs) that would persist until today. The nature of the inflaton's coupling to Standard Model or other fields is…

During or towards the end of inflation, the Standard Model (SM) Higgs forms a condensate with a large amplitude. Following inflation, the condensate oscillates, decaying non-perturbatively into the rest of the SM species. The resulting…

In this talk, based on arXiv:2301.11345, arXiv:2305.16388, arXiv:2311.12694, we discuss the production of primordial gravitational waves (GW) sourced by graviton bremsstrahlung during inflationary reheating. For reheating, we consider…

In warm inflation, dissipation due to the interactions of the inflaton field to other light degrees of freedom leads naturally to the enhancement of the primordial spectrum during the last 10-20 efolds of inflation. We study this effect in…

We investigate the reach of future gravitational wave (GW) detectors in probing inflaton couplings with visible sector particles that can either be bosonic or fermionic in nature. Assuming reheating takes place through perturbative quantum…

The primordial gravitational waves (\textbf{PGW}) have been generated by inflationary amplification of the primordial (quantum) fluctuations. It is true that they have not been recorded directly so far, but their spectrum can help a lot in…

We propose that there may be a substantial stochastic gravitational wave background from particle origin, mainly from the gravitational three-body decay of the inflaton. The emitted gravitons could constitute a sizable contribution to dark…

We revisit graviton production via Bremsstrahlung from the decay of the inflaton during inflationary reheating. Using two complementary computational techniques, we first show that such 3-body differential decay rates differ from previously…