The modified supergravity approach is applied to describe a formation of Primordial Black Holes (PBHs) after Starobinsky inflation. Our approach naturally leads to the two-(scalar)-field attractor-type double inflation, whose first stage is driven by scalaron and whose second stage is driven by another scalar field which belongs to a supergravity multiplet. The scalar potential and the kinetic terms are derived, the vacua are studied, and the inflationary dynamics of those two scalars is investigated. We numerically compute the power spectra and we find the ultra-slow-roll regime leading to an enhancement (peak) in the scalar power spectrum. This leads to an efficient formation of PBHs. We estimate the masses of PBHs and we find their density fraction (as part of Dark Matter). We show that our modified supergravity models are in agreement with inflationary observables, while they predict the PBH masses in a range between \(10^{16}\) g and \(10^{20}\) g. In this sense, modified supergravity provides a natural top-down approach for explaining and unifying the origin of inflation and the PBHs Dark Matter.

修改后的超重力方法用于描述Starobinsky膨胀后原始黑洞（PBH）的形成。我们的方法自然导致了两（标量）场吸引子型双膨胀，其第一阶段由标量驱动，而第二阶段由另一属于超重力多重性的标量场驱动。推导了标量势和动力学项，研究了真空，并研究了这两个标量的膨胀动力学。我们通过数值计算功率谱，并发现超慢摇机制会导致标量功率谱增强（峰值）。这导致PBH的有效形成。我们估算PBH的质量，并找到它们的密度分数（作为暗物质的一部分）。\（10 ^ {16} \） g和\（10 ^ {20} \） g。从这个意义上讲，改进的超重力提供了一种自然的自上而下的方法来解释和统一通货膨胀和PBH的“暗物质”的起源。