Colloquium

  • Exploring the universe with gravitational waves

  • Speaker : Prof. Chunglee Kim
    Affiliation : Department of Physics, Ewha Womans University
    Date : June 9, 2021 12:00 AM
    Place : Zoom Conference Room: Physics Seminar 2021-1 (ID: 835 7220 3524, Password:1882)
    Contact : agatha0206@unist.ac.kr (Youn-young Hwang, Academic & Student Affairs Team)
    Host : Prof. Kyujin Kwak(kkwak@unist.ac.kr)
  • Abstract

  • The discovery of GW150914 shows some black holes do merge and the coalescence of a binary black hole (BBH) can be “directly observable” with gravitational waves (GWs). Stellar-mass BBHs such as GW150914 are observable with km-scale laser interferometry in the GW frequency range of 10-2000 Hz. For stellar-mass black holes, individual masses and the final black hole formed from the coalescence can be measured by GW observation with impressive accuracy. The distance to the source is also measurable and BBHs are suggested as ‘standard sirens’ that can constrain a Hubble constant. In this talk, I will give an overview on the progress made in GW science focusing on stellar-mass black holes and discuss their implications in astrophysics and cosmology. Black holes have a broad mass spectrum and different GW observation techniques have been suggested to explore different black hole populations. For example, supermassive BBHs are main targets for the pulsar timing array that utilises precision timing of millisecond radio pulsars at nano Hertz frequencies of GW signals. If time allows, I will briefly introduce international efforts to observe supermassive black hole binaries in the context of multimessenger astronomy.