(I don't have a specific question here, but observations/insights on the above paper or following excerpts are welcome....) Marcus posted the above in another thread...And I do wish he would STOP that type of thing because everytime I read another paper I discover something else I had not thought about and therefore clearly do not understand!!!! (just joking,partly, but it never seems to end...peeling a layer simply reveals yet another layer...) OMG, not only is space and time frame dependent, seems like particles are too...and in more ways than simply the virtual particle pairs of Unruh... So there are some fundamental differences among theorists about what particles are.... So we are back to the old reliable, "I don't know exactly what it is, but at least I can measure whatever it is....thank heaven for "observables"...." This sounds reminisescent not only of the Unruh effect but also things like "relativity of simultaneity" and the apparent affects of gravity (curved spacetime) on local versus distant time....is nothing constant in this universe except lightspeed????