Separating dark matter from regular matter

45:38question and it's one of the main challenges in my research is finding ways to model these gravitational lens systems in a way that allows you to disentangle uh the two uh the two signals, right? One of them is dark matter, the other one is regular matter. They're both producing a gravitational lensing effect and we want to isolate the one from these clumps. What helps is that these clumps, they look very different or they're predicted to look very different from a galaxy, right? So, they are these concentrated blobs of mass uh whereas uh the galaxy that you know the the one that we were just looking at, maybe we can pull it up here again number seven. Yep.

46:19Right? It looks uh you know that the scales here are are a little bit uh difficult to to comprehend, I think, but you know this galaxy is much uh it does not look like the clumps that we're looking for. So, we we can use the fact that the predicted property of these dark matter halos produces a a very different kind of lensing effect from the galaxy itself and from the regular matter and that allows us to to disentangle them. And again, that's a prediction of the theory, right? That we're testing. Uh if you had no information, if you had no idea what you were looking for that then the task would be a lot harder.

47:00>> Right, right. And so, and this comes back to kind of I think understanding what you're you know, I think now we have a good structure and setup for myself and the listeners on, okay, what is dark matter? Why do we think it exists? Uh how have what are the ways in which we've tried to um prove its existence. We talked about galaxy rotation curves versus now gravitational lensing. What is lensing? Why does it happen? Um and as we look to better characterize dark matter, um measuring uh looking at and measuring

47:43uh