Teacher problems

[RandyDogz]

That's a well constructed explanation, and I'll concede you're more knowledgable about the underlying science than I am. I get the gravitational lensing idea, but I just have snippets of knowledge, haven't really dived into it yet.

I'm still not convinced that the answer is more matter, and not some other as of yet undiscovered force. I believe the rate if expansion of the universe is accelerating, rather than decelerating as previously assumed, as another example there's more going on than we can explain with current theories? I like the bubble galaxy idea, that could explain why things don't work as expected out there?