Talk detail

Participant	Lee, Wonwoo
Institution	CQUeST (Center for Quantum Spacetime) - Sinsu-dong - Seoul - Mapo-gu - South Korea

Session	CM4	Accepted	Yes	Order	7	Time
Talk	Oral abstract	Title	The nucleation of the thick wall for topological inflation by oscillating instanton solutions
Co-authors	Bum-Hoon Lee and Chul H. Lee
Abstract	We investigate oscillating instanton solutions of a self-gravitating scalar field between degenerate vacua. We show that there exist O(4)- symmetric oscillating solutions in a de Sitter background. The geometry of this solution is finite and preserves the Z_2 symmetry. The nontrivial solution corresponding to tunneling is possible only if the effect of gravity is taken into account. We present numerical solutions of this instanton, including the phase diagram of solutions in terms of the parameters of the present work and the variation of energy densities. Our solutions can be interpreted as solutions describing an instanton-induced domain wall or braneworld-like object rather than a kink-induced domain wall or braneworld. The oscillating instanton solutions have a thick wall and the solutions can be interpreted as a mechanism providing nucleation of the thick wall for topological inflation. We remark that Z_2 invariant solutions also exist in a flat and anti-de Sitter background, though the physical significance is not clear.