Abstract: We live in an era of breakthrough discoveries in gravitational waves (GW) astronomy. Every month or so, such discoveries by LIGO/Virgo have been making headlines because the nature of these events has been far from the expectations. But why are we puzzled? And what is the road ahead for us to a deeper understanding? I discuss two of the puzzling events that LIGO has discovered: 1) The most massive binary black hole merger with masses above the pair-instability limit. After a deep dive into the physics of pair-instability supernova, I will discuss how a broader perspective on the host environment of binary black holes can hold the key to understanding the nature of such massive systems. 2) The most massive binary neutron star merger. I will present possible scenarios to explain why we have not detected such systems in the radio observations before and how the key to understanding these events might lie in the r-process enrichment in the early universe and magnetic field evolution of neutron stars. Through these two examples, I will conclude that the synergy of traditional electromagnetic-wave astronomy with gravitational wave astronomy is essential for gaining insights into the surprises that are being uncovered with these new observations.
The Astrophysical Context of Gravitational Wave Events
Mohammad Safarzadeh (CfA, Harvard) // December 2, 2021
Abstract: We live in an era of breakthrough discoveries in gravitational waves (GW) astronomy. Every month or so, such discoveries by LIGO/Virgo have been making headlines because the nature of these events has been far from the expectations. But why are we puzzled? And what is the road ahead for us to a deeper understanding? I discuss two of the puzzling events that LIGO has discovered: 1) The most massive binary black hole merger with masses above the pair-instability limit. After a deep dive into the physics of pair-instability supernova, I will discuss how a broader perspective on the host environment of binary black holes can hold the key to understanding the nature of such massive systems. 2) The most massive binary neutron star merger. I will present possible scenarios to explain why we have not detected such systems in the radio observations before and how the key to understanding these events might lie in the r-process enrichment in the early universe and magnetic field evolution of neutron stars. Through these two examples, I will conclude that the synergy of traditional electromagnetic-wave astronomy with gravitational wave astronomy is essential for gaining insights into the surprises that are being uncovered with these new observations.