Cosmological scenario based on inhomogeneous models

空洞模型为宇宙在没有暗能量的情况下“加速膨胀”提供了可能的解释。为了使传统的空洞模型更加逼真，我们允许空洞是各向异性的，并考虑观察者所覆盖的立体角度上的距离-红移关系的平均值。我们首先证明了在取一种形式的光学标量方程(距离方程)的平均值后，我们得到的有效距离方程与具有Dyer-Roeder类扩张的Lema^itre-Tolman-Bondi宇宙的有效距离方程重合。然后，我们数值求解该方程，并与Ia型超新星的观测数据进行比较。我们发现，各向异性允许较小的空洞尺寸和较大的Ωm。

Void models provide a possible explanation of the "accelerated expansion" of the Universe without dark energy. To make the conventional void models more realistic, we allow the void, an under-dense region around us, to be anisotropic and consider an average of the distance-redshift relations over the solid angle subtended at the observer. We first show that after taking the average of a form of the optical scalar equation (distance equation), the effective distance equation we obtain coincides with the one for the Lema^itre-Tolman- Bondi universe with a Dyer-Roeder-like extension. We then numerically solve the equation to compare with observational data of Type Ia supernovae. We find that anisotropy allows smaller size of void and larger Ωm.