Ok, here we go with links to papers on cosmic inhomogeneity as an explanation for the observed anomaly in SN-1a luminosities:
David Wiltshire, Cosmic clocks, cosmic variance and cosmic averages,
New J Phys 9, 377, available
here
David Wiltshire, Viable inhomogeneous model universe without Dark Energy from primordial inflation, available
here
Leith, Ng and Wiltshire, Gravitational energy as Dark Energy: Concordance of Cosmological Tests,
ApJ 672, L91 - L94; available
here.
David Wiltshire, Dark energy without Dark Energy, available
here is a good overview paper of Wiltshire’s model. (Note that Wiltshire’s model depends on a local void with a radius of about 170Mpc, much smaller than the observable universe - he calls it the Fractal Bubble model. The model yields an age for the universe significantly greater than the concordance FRW model)
David Wiltshire, Gravitational energy as dark energy: Average observational quantities, available
here, discusses possible observational tests for his model.
Mattsson, Dark Energy as a Mirage, available
here, is a model that depends on local inhomogeneities and which maintains the large scale homogeneity of the universe (as does Wiltshire’s)
Syksy Rasanen, Evaluating backreaction with the peak model of structure formation, *JCAP *0804:026, available
here
Syksy Rasanen, On the relationship between the isotropy of the CMB and the geometry of the universe, available
here
Sysky Rasanen, Structure Formation as an alternative to Dark Energy and modified gravity, available
here who uses non-linear effects in structure formation to generate the apparent late epoch acceleration
Marie-Noelle Celerier, The Accelerated expansion of the Universe challenged by an effect of the inhomogeneities,
New Adv Phys 1, 29, available
here is a detailed review paper with enough additional references to other inhomogeneous models to keep you busy for weeks - one major conclusion is that she derives a strong argument (and references other arguments) that inhomogeneities must be on a subhorizon scale, ie smaller than the observable universe, in order to predict what we see. The following paper concurs:
Kolb et al, On cosmic acceleration without Dark Energy,
New J.Phys 8, 322, available
here
Alexander et al, Local void versus Dark Energy:Confrontation with WMAP and Type 1A supernovae,
JCAP 0909, 025, available
here also derive a subhorizon sized void of the order of 300 Mpc
Clarkson et al, A general test of the Copernican Principle,
Phys Rev Lett 101, 011301available
here propose a test for large scale homogeneity in the universe.
You’ll note that most of these models rely on inhomogeneities that are smaller in scale than the observable universe, although there are some proposals that make the void about the Hubble scale. The following papers propose superhorizon inhomogeneity:
Kolb et al, Primordial inflation explains why the Universe is accelerating today, available
here
Barausee et al, The Effect of Inhomogeneities on the Luminosity Distance–Redshift Relation:is Dark Energy Necessary in a Perturbed Universe?, available
here
However this paper shows (as does Celerier above), that the inhomogeneity scale must be sub-horizon:
Hirata and Seljak, Can superhorizon cosmological perturbations explain the acceleration of the universe,
Phys Rev D 72:083501, available
here
As you can see, there is a lot of work going on here looking at possible inhomogeneities to explain the supernovae data without the need for Dark Energy - actually there is a lot more than I referenced here. There is an equal amount of energy going into hypotheses that depend on modified gravity and variances of GR.
Enjoy.
Alec
evolutionpages.com