4 papers
Nambu-Goldstone emissions from the cosmological evolution of global monopoles
Yukihiro Kanda, Naoya Kitajima
We show the emission of the Nambu-Goldstone (NG) bosons from the cosmological evolution of global monopoles. The NG bosons are non-thermally produced from the dynamics of global mo…
Emission of Nambu-Goldstone bosons from the semilocal string network
Yukihiro Kanda, Naoya Kitajima
Semilocal cosmic string is a line-like non-topological soliton associated with the breakdown of the symmetry to the …
Primordial black hole formation from the merger of oscillons
Kentaro Kasai, Naoya Kitajima
We show that the merger of oscillons results in a broad spectrum of the oscillon mass. A huge number of oscillon samples obtained from numerical lattice simulations reveal that the…
Primordial black hole formation from collapsing domain walls with full general relativity
Naoya Kitajima
We study the dynamics of isolated closed domain walls with 3+1 numerical relativity. A closed wall shrinks due to its own surface tension, and its surface energy is converted to th…