Looking for dark matter with GPS

I don’t get to do as much astronomy as I would like and so keeping up to date with what’s going on in that field is left to crumbs falling off the table.

Here is something of that nature.

Some physicists have been exploring the idea that dark matter might be ‘topological defects’ in a quantum field. Rather than solid particles, these would be perturbations, or oscillations.

This week, two physicists proposed a way to look for such defects using only atomic clocks. Atomic clocks are “arguably the most accurate scientific instruments ever built,” the researchers write in their paper. And, crucially, the clocks necessary already exist in the form of our GPS system.

We (the human race) is still trying to figure out what most of universe is made of. For the longest time, its simply been called ‘dark matter’.

Some latest thinking is that we should be able to test a newish theory on it using the atomic clocks that exist in GPS satellites.

Hope this one gets some legs as I can see more than just this test coming out of it – like understanding jitter in atomic clocks and relativity – time compressing in front of a moving clock and expanding behind it.

While this gives a high degree of certainty about measurements by the prospective network, it is also susceptible to a lot of noise. As with many other experiments designed to look for elusive objects from space, it’s very important to rule out as much noise as possible in such an experiment. While GPS satellite clocks are affected by things like solar flares and temperature, none of these will propagate through the network at 300 kilometers per second like the topological defects will. For this reason, the scientists are confident that the defect cloud signal should stand out from the noise and be detectable.

There would be a lot of data to come out of this experiment, looking through the noise for a signal could be a useful outcome as well.