Dear Elemental
> it only works if you make special assumptions about conditions at infinity (which appear unwarranted based on astronomy).
I have heard and attempted to read something about "boundary conditions," here.
Khoury, J., & Parikh, M. (2006). Mach’s Holographic Principle...
> How can there be an intimate relation between something far away out there and local events?
If there is a lot of mass out there then even if it is distant it can still exert a gravitational pull that some have termed "star suck."
I am not sure if this is relevant but interestingly, Mach is...