Gravitational Lensing and the Dark Matter Episode

There was a long while where people are running. Is this really extra matter we can't see? Or is it that on these very long cosmological scales something different is going on with gravity, which Einstein had to revise gravity before from the Newtonian analysis. So weak lensing eventually gave us a way to answer the question there. And we were able to find examples where it was very obvious that there was invisible matter going on and you couldn't explain it. From the overall community perspective, I'd say that it's pretty solidly of the theory that dark matter does exist. It's some unknown thing, which we don't know what it is. There doesn't seem to be a