| > The clever thing about interferometers is that they're actually measuring space and time in two different dimensions concurrently I would say that we measure space in two different directions concurrently. > and then looking for changes in the interference pattern between light moving along each of the dimensions This is true, but I like to push back against the use of the phrase "interference pattern." We're not looking at a "pattern", which to me brings to mind a complicated interference pattern resolved spatially. We do not resolve the "interference pattern" spatially. We measure the amplitude (er, power) of the light coming out of the interferometer with a photodiode (a single pixel, if you will.) > In practice, gravitational waves will come from all sorts of weird angles, but they will distort each of the two dimensions differently This is true. The detector's sensitivity to waves coming from different directions is the "antenna pattern." > t they will distort each of the two dimensions differently and allow us to figure what direction they were propagating by the interference pattern that's observed. With a single detector, we cannot determine the direction in which a g.w. is propagating. With a single detector and a transient (short-lived) source, we cannot tell the difference between a loud source in a direction where the detector is not very sensitive versus a quieter source in a direction where we have good sensitivity. With a network of detectors and/or signals that persist for a long time (compared to the rotation of the earth, etc) we can resolve the source direction. |