[specialp]

Keep in mind that when LIGO was built at tremendous expense, gravitational waves were never conclusively detected, and just to get to this sensitivity it was a feat of engineering. It was unknown how long it would be or if they would ever detect a wave.

Just detecting the initial wave was one of the most important measurements in the history of physics. Now that we know that gravitational waves exist, and can give us great insight into the mysteries of the universe, there will be more efforts to detect waves at smaller amplitudes and different frequencies. That is one reason the eLISA project is going on [1].

1. https://en.wikipedia.org/wiki/Laser_Interferometer_Space_Ant...

[privong]

I'm aware of the context for the GW detections and the expense, etc. I was making a general philosophical point about "overpaid", not commenting specifically on the LIGO cost-benefit analysis.