What can gravitational lenses be used for?
I'm currently a high school student working on a machine learning project involving strong gravitational lensing. I'm still new but going through some research papers and I'm wondering the real applications of gravitational lenses. Based on what I've seen, gravitational lensing has two main applications:
Seeing distant galaxies (like a huge magnifying glass)
Finding the mass of certain objects (stars, dark matter, etc.)
What I’m trying to understand better is why these things are useful in practice. For example, how important is gravitational lensing for actually discovering new galaxies or studying early galaxy formation? And when it comes to mass measurements, can we realistically map dark matter in galaxies or galaxy clusters using it, or measure the mass of specific objects in a meaningful way?
I’m also curious about how this connects to real research today. Are gravitational lenses mostly a supporting tool, or do they lead to discoveries we couldn’t make any other way? And how might machine learning fit into improving lens detection, mass modeling, or dark matter mapping (if anyone knows anything about this)?
Any help would be greatly appreciated, thanks!