Black Holes: Theory

• Size and recipe
• Black holes from afar, near, and inside
• Black hole inspiral and collisions

Evidence for Black Holes

• X-ray binaries: Cygnus X-1
• Milky Way center:
  • Radio overview
  • The power of adaptive optics
  • Stellar orbits: Munich group, UCLA group
  • possibly related: gamma-ray bubbles
  • coming soon(?): Event Horizon Telescope image of a black hole, perhaps like this, this, or this
• other galaxies
  • active galaxies: M87; AGN gallery
  • gravitationally lensed quasar: the Einstein cross
  • quasar and host galaxies
  • supermassive black holes
  • black holes and galaxies somehow know about each other
  • important clues: a binary supermassive black hole pairs and even triples! optical detection by our own Prof. Xin Liu, X-ray

Gravitational Radiation

• Theory: ripples in spacetime
• Indirect evidence: Hulse & Taylor's award-winning binary pulsar
• Direct detection: gravity-wave observatories
  • Advanced LIGO: detectors in Hanford and Livingston
  • VIRGO: detector near Pisa, Italy
  • the future: LIGO India, KAGRA, Japan, LISA
• Welcome to the era of gravity wave astronomy!
  • merging black holes
  • merging neutron stars
  • Nobel Prize 2017: Rainer Weiss, Barry Barish, Kip Thorne