This may be out there a little but I want to put forth the idea that since I believe relativity states that space and time are relative and Einstein is correct to state nothing can travel further than light can in a second within the observer’s space-time. That it is actually this limit on the high side that defines our dimensional upper limit. So if some object at a much higher inertial constant velocity were actually able to send something no faster than the speed of light for their time line but that actually did exceed the velocity of light in our world line it would no longer exist within our observable dimension. I am not sure but I bet some of the “spookyness” that particle physicists observe are just observations of objects entering and leaving our own dimension at the lowest limit of our dimension. And since we take for granite that other dimensions exist this seems like the most clear understanding of what they are. And if this is true could the dark matter just be traveling outside our observable dimension?