Using the data of the Pierre Auger Observatory, we report on a search for signatures that
would be suggestive of super-heavy particles decaying in the Galactic halo. From the lack of …

Instantons, which are nonperturbative solutions to Yang-Mills equations, provide a signal for
the occurrence of quantum tunneling between distinct classes of vacua. They can give rise …

In the so-called Planckian Interacting Dark Matter (PIDM) scenario, superheavy dark matter
particles are produced after inflation by gravity-mediated interactions through the freeze-in …

We propose an inflationary scenario where the inflaton field is non-minimally coupled to
spacetime curvature and inflation is driven by a vacuum energy symmetry breaking potential …

A bstract Starting with the de Broglie-Proca Lagrangian for a massive vector field, we
calculate the number density of particles resulting from gravitational particle production …

We generalize dark matter production to a two-metric framework whereby the physical
metric, which couples to the Standard Model (SM), is conformally and/or disformally related …

Dark matter may only interact with the visible sector efficiently at energy scales above the
inflaton mass, such as the Planck scale or the grand unification scale. In such a scenario, the …

Conventional scenarios of purely gravitationally produced dark matter with masses below
the Hubble parameter at the end of inflation are in tension with cosmic microwave …

We study the nonadiabatic cosmological production of ultralight dark matter (ULDM) under a
minimal set of assumptions: a free ultralight real scalar as a spectator field in its Bunch …

A period of early matter domination can give rise to the correct dark matter abundance for a
broad range of dark matter annihilation rate⟨ σ ann v⟩ f. Here, we examine this scenario for …