What Dan actually does — strong gravitational lensing

22:15>> Yeah, so what I do uh to study these dark matter clumps and you know, by I mean you know, my collaboration and myself. So we use an effect called gravitational lensing. So this is the the bending of light by gravity. Uh and we we use that effect to try to study uh the properties of these dark matter clumps. And I can come back uh you know, a a little bit later to give some more ideas, but the but you know, the the main picture is that we will take our best theories for what dark matter can be. We will predict from those theories what the properties of these clumps are and then we'll try to simulate how that would change the deflection of light

22:57uh you know, around astronomical objects in a way that we can measure and detect statistically. >> Okay, so that's the kind of structure of like, you know, how it is we're going to go about this process. Um, where do you think is the best place to start in trying to understand this? Again, I'm really curious about how like what is it that you do? >> Yeah, yeah. So, let me uh Let me uh let me let me try to explain lensing a little bit more and then once uh once uh we have a clear understanding of what gravitational lensing is, then I'll I'll give you some more details about the day-to-day. >> Makes sense. >> So, why don't we start with uh number two? >> Number two, let's pull that up.

23:39>> So, this was uh one of the first images released by the uh by NASA after the James Webb Space Telescope went into space. Uh and this is a cluster of galaxies. >> Mhm.