We forecast constraints on minimal model-independent parametrisations of several Modified Gravity theories using mock Stage-IV cosmic shear data. We include nonlinear effects and screening, which ensures recovery of General Relativity on small scales. We introduce a power spectrum emulator to accelerate our analysis and evaluate the robustness of the growth index parametrisation with respect to two cosmologies: ΛCDM and the normal branch of the DGP model. We forecast the uncertainties on the growth index γ to be of the order ∼ 10%. We find that our halo-model based screening approach demonstrates excellent performance, meeting the precision requirements of Stage-IV surveys. However, neglecting the screening transition results in biased predictions for cosmological parameters. We find that the screening transition shows significant degeneracy with baryonic feedback, requiring a much better understanding of baryonic physics for its detection. Massive neutrinos effects are less prominent and challenging to detect solely with cosmic shear data.

中文翻译：

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具有修正重力和模型独立筛选的 IV 阶段宇宙剪切


我们使用模拟 IV 阶段宇宙剪切数据预测了几个修正引力理论的最小模型无关参数化的约束。我们包括非线性效应和筛选，这确保了广义相对论在小尺度上的恢复。我们引入了一个功率谱仿真器来加速我们的分析，并评估增长指数参数化在两种宇宙学方面的稳健性：ΛCDM 和 DGP 模型的正常分支。我们预测增长指数的不确定性γ约为 ∼ 10%。我们发现，我们基于 halo 模型的筛查方法表现出出色的性能，满足 IV 阶段调查的精度要求。然而，忽视筛选转换会导致对宇宙学参数的预测有偏差。我们发现筛选转变显示出具有重子反馈的显着简并性，需要更好地理解重子物理学才能进行检测。大块中微子效应不太突出，仅用宇宙剪切数据很难检测到。