AbstractHopfions are a family of `solitonary solutions of the N-spin field with a non-trivial topologicalstructure related to Hopf fibration. During the talk, l wil focus on electromagnetic and linearizedgravity cases. Conserved guantities, in particular energy and topoloaical charges, will be discussedRecent attempts at generalization of hopfions will also be presented
AbstractEstimating the spin of SgrA* is one of the current challenges we face in understanding the centerof our Galaxy. We show that detecting the gravitational waves (GWs) emitted by a brown dwarfinspiraling around SgrA* will allow us to measure the mass and the spin of SgrA* withunprecedented accuracy. Such systems are known as extremely large mass-ratio inspirals (XMRls)and are expected to b...