(March 2, 2018 at 9:19 pm)Banned Wrote:(March 2, 2018 at 6:55 pm)polymath257 Wrote: Well, in a sense, that is how we discovered dark matter and how we investigate its properties. Dark matter doesn't interact with ordinary matter or light very strongly (if at all). So in a sense, it satisfies your criteria.
We use the way that dark matter bends light to map out where it is and how much is there. We do that by looking at slight distortions in the way light travels from more distant objects. So, there is a sense in which we are detecting the water just as you suggested.
That's what I was thinking, although I haven't heard of applying dark matter to light bending.
Here is a recent article using 'micro-lensing' to map out the distribution of dark matter.
https://www.sciencedaily.com/releases/20...101807.htm
Here, the lensing is from the interaction of the light with gravity produced from the dark matter.
Previously, larger scale lesning has been used to detect dark matter in clusters of galaxies, which was one way we concluded that dark matter really exists (as opposed to a difference in the law of gravity causing the effects we see).
