We don't need no stinkin dark energy II
David Wiltshire has opened a new front in the dark energy wars with gr-qc/0503099 . He has an allegedly simple and exact model using the Kolb, Matarrese, Notari and Riotto (KMNR) idea of super-Hubble density variations to explain apparent cosmic acceleration without dark energy. I have been trying to understand his "spirit of Mach's principle" assumption. My current guess goes like this: At the end of inflation, the universe was nearly flat and uniform in density, so that FRW "comoving" coordinates closely approximated the actual geodesics. As the density variations amplified with time, these coordinates increasingly deviate from geodesics. Here is what I consider the money quote: "...an observer who would measures no dipole anisotopy even in the observable universe, must be referred to the time, t..." I think that means he is assuming that the observers measuring no dipole anisotropy are the ones moving along those (non-geodesic) FRW t coordinate