报告题目：The Simplest Oscillon and its Sphaleron

报告人：Tomasz Romańczukiewicz and Nick Manton

单位：雅盖隆大学&剑桥大学

时间：2023年3月1日21:00

ZOOM ID：210-089-8623

密码：123456

摘要：We have constructed a small-amplitude oscillon solution for a simple 1-d scalar field theory with cubic potential, using the Fodor et al.expansion. The theory also has an exact sphaleron solution, which can decay slowly, via a larger-amplitude oscillon. The sphaleron's two discrete linearised modes, the unstable mode and a vibrational mode,provide a useful truncation of the field theory, connecting the sphaleron and the oscillon. We show how these various approximations tie together.

简介：Prof. Nicholas Manton is an Emeritus Professor at the University of Cambridge, UK, and is an expert on topological solitons of all kinds.Manton was the group leader of the field theory division of the Department of Applied Mathematics and Theoretical Physics (DAMPT) for many years. Manton is famous for the Manton approximation or the moduli space approximation, which is the low-energy effective description of solitons with zeromodes or moduli, that gives a geometric and mathematical method for studying dynamical or ergodic problems. Manton is also accredited as the inventor of sphalerons, which are saddle point solutions in field theories and are relevant for cosmological considerations, including the creation and annihilation of dark matter particles. Manton is the coauthor of the monograph in mathematical physics "Toplogical Solitons" from Cambridge University Press and the single author of the two text books: "The Physical World: An Inspirational Tour of Fundamental Physics" and "Skyrmions - A Theory of Nuclei". Manton has published over 100 papers in Physical Review Letters, Journal of High Energy Physics, Communications in Mathematical Physics, Journal of Physics A: Mathematical and Theoretical, Physical Review D, Physical Review C, Nuclear Physics B and many other journals with over 9600 citations.