LISA Science Talks February 2, 2007Posted by gordonwatts in physics, science.
I mentioned the great talk Craig Hogan gave about the proposed LISA project. He and others will be giving these talks around the country: they have just finished a science review and are trying to influence the NASA Beyond Einstein committee (well, to make sure they have all the facts!).
- A discussion of the science that LISA might or might not see
- A discussion of the space mission (note that Craig is a theorist, as he repeated noted while he was giving this portion of the talk).
The 1/2 a billion project has a lot going for it. It is “cool” (heck, three laser interferometers trailing the earth spaced at a distance of 5 million kilometers – you don’t get much cooler than that). There is a lot we don’t know about how stars interact. Well, I should say there is a lot we do know, and there are some rather distinctive signals that LISA might show and that would tell us how good our model was. And, finally, an argument that has been made a lot in the halls of UW is that every time you turn on a new telescope you see something new and unexpected (i.e. the Cosmic Microwave Background). Finally, there is way more dark matter than any other kind of matter and we know it does interact gravitationally (and we don’t know much else), so why not have something that is sensitive to gravity!?
I’m not entirely convinced of the science case. For one thing this will really be the first instrument that we can build to study gravity waves. You might point to LIGO, in southern Washington. That is a great prototype, indeed. But its sensitivity, unfortunately, is severely limited — and only just begins to touch on what we might see with LISA. 1/2 a billion bucks is a big leap. And if you do see gravity waves that you can’t explain (i.e. that are due to dark matter) what do you learn over things like the galaxy crashing observation?
On the other hand, they are talking about real international collaboration (indeed, the Europeans seem to be out ahead of the US when it comes to this — something that is happening more and more often) which should reduce the USA price tag.
Heck. What we really need is for the science budget to get a good boost! Then this would be totally worth it!