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When you think to the future you know both in terms of the devices and things that we might find, what gets you most excited?
Well, I think there are two things two directions we can go, go well beyond advanced LIGO, and well beyond probably makes it from initial LIGO to advanced LIGO was a factor of 10 sensitivity because we look at the amplitude of waves I’m being able to reach our a factor of 10 times further brings a thousand times as many possible sources into our reach. Probably the next step would be another factor of 10 on ground, and there are couple of different ideas that how to do that I mentioned that one of the limits to what we can see is the thermal noise and one thing you could to do is to refrigerate the masses down to a fraction of a kelvin or maybe something not quite as cold to reduce the thermal noise. Another way you can do it, this is a strain in space. If you have a meter stick, it will change by 10 to the minus 21 meters when the wave goes by. If you have a 10-meter stick, you will change by 2 minus and it’s 20 ten times more. So we have 4-kilometer long arms to take advantage of that. Now if we had say 40-kilometer long arms, that would make the signal 10 times’ bigger without any of our noise sources growing that by that same amount. So there are couple of ideas we have for how we could grow ground-based interferometers and the systems that could reach even further back and say get to the point where we can see the very first black holes, see all the black holes in the universe. I think though the other thing there was an image upon the screen a little while ago of a, the constellation of satellites and space. It’s obvious that the experiment that must be done. It would probe not the same frequency range of gravitational waves, so it’s a little bit like a radio astronomy or optical astronomy, but would be also a place where you can instead of having a mere 40-kilometer long arm and you could have a-million kilometre long arms and have signals which is that much larger and be able to probe with incredible precision the wave form of the gravitational waves use it as a used small black holes orbiting around big black holes as a way of mapping out the curvature space time in more detail. It’s an experiment which must be done.
