Was the Gravitational Wave Background Finally Discovered?
A few weeks ago a large team of gravitational wave astronomers announced something pretty wild.
2023-07-26 22:00:00 - PBS Space Time
The moderately confident detection of pervasive ripples in the fabric of space time that presumably fills the cosmos, detected by watching for subtle connections between the signals from rapidly spinning cores of dead stars in our galactic neighborhood.
In other words, the gravitational wave background has probably been detected using a pulsar timing array.
00:00 Introduction
01:02 Relativity and Gravitational Waves
02:21 Discovering Gravitational Waves
03:49 Gravitational Waves & Pulsars
05:04 Pulsar Timing Array Discovers GWB
06:48 Understanding the GWB
07:55 Are Pulsars Seeing Gravitational Waves?
09:00 Correlated & Anti-Correlated Pulsar Rates
10:07 Hellings and Downs Curve
11:44 Binary Supermassive Black Holes
13:39 NANOgrav Frequency Spectrum