Alexander Petrov: Riemann-Hilbert correspondence for $B_{\mathrm{dR}}^+$-local systems
Abstract: Let $X$ be a smooth proper variety over $\mathbb C_p$, and suppose that it is equipped with a lift to a smooth scheme over the period ring $B_{\mathrm{dR}}^+$. Given a choice of an exponential map on $\mathbb C_p$, we produce an equivalence of categories between vector bundles with a t-connection on that lift, and locally free modules over the period sheaf $\mathbb B_{\mathrm{dR}}^+$ on the pro-etale site of (the analytification of) $X$. This equivalence is a deformation of the $p$-adic Simpson correspondence between Higgs bundles and pro-etale vector bundles on $X$. It may also be viewed as a partial $p$-adic analog of the construction of Simpson, associating a variation of twistor structures to any semi-simple $\C$-local system on a smooth proper variety over $\C$ ('partial' here accounts for the fact that we are only producing a a $t$-connection over a formal thickening of $X$). I hope to explain two perspectives on this result: one relying on the notion of $t$-$D$-modules twisted by the Simpson gerbe, and the other using the transmutation point of view on the categories in question, afforded by the analytic prismatization. This is joint work with Bhargav Bhatt, Ben Heuer, and Vadim Vologodsky.