LIGO Misses 100,000 Black Hole Mergers A Year
“The era of gravitational wave astronomy is now upon us. Owing to the incredible capabilities of ground-based detectors like LIGO and Virgo, we have now detected six robust events over the past 2+ years, from black holes to merging neutron stars. But huge questions surrounding the black holes in the Universe, such as how many there are, what their masses are early on compared to today, and what percent of the Universe is made of black holes, still remain to be answered. The direct efforts have gotten us a very long way, but the indirect signals matter, too, and can potentially teach us even more if we’re willing to make inferences that follow the physics and math. LIGO may be missing upwards of 100,000 black hole-black hole mergers a year. But with this new proposed technique, we might finally learn what else is out there, with the potential to apply this to neutron stars, non-merging black holes, and even the leftover ripples from our cosmic birth. It’s an incredible time to be alive.”
When you look up at the stars in the night sky, you think you’re seeing just countless numbers of them. It’s beautiful what’s out there, as you look up and take it all in. Break out the binoculars, and things get even more spectacular. Yet even with that assist, you’re missing nearly a million stars for every one you can see. That’s the same situation with black hole and neutron star mergers, where LIGO and Virgo have seen a total of six, but have missed nearly a million over the multiple years they’ve been running. Directly, there’s no way to see them with our current equipment. But from an aggregate computational perspective, we might be able to extract the true signal and know, at least statistically, how many black hole mergers are occurring in our Universe overall.