We develop a theory ofétale parallel transport for vector bundles with numerically flat reduction on a p-adic variety. This construction is compatible with natural operations on vector bundles, Galois equivariant and functorial with respect to morphisms of varieties. In particular, it provides a continuous p-adic representation of theétale fundamental group for every vector bundle with numerically flat reduction. The results in the present paper generalize previous work by the authors on curves. They can be seen as a p-adic analog of higher-dimensional generalizations of the classical Narasimhan-Seshadri correspondence on complex varieties. Moreover, they provide new insights into Faltings' p-adic Simpson correspondence between small Higgs bundles and small generalized representations by establishing a class of vector bundles with vanishing Higgs field giving rise to actual (not only generalized) representations.
MSC: 14J20, 11G252 Numerically flat bundles Throughout this paper, a variety over a field k is a geometrically integral separated scheme of finite type over k. Recall that a scheme is called integral if it is irreducible and reduced.We want to study the following class of vector bundles which was introduced in [DMOS82] (2.34).Definition 2.1 Let X be a connected and complete scheme over a perfect field k. A vector bundle E over X is called Nori-semistable if for all k-morphisms f : C → X from smooth connected projective curves C over k into X the pullback f * E is semistable of degree zero.A related but different notion is due to Nori [Nor82] who considers only pullbacks to embedded smooth projective curves. In [DMOS82] the bundles in Definition 1 are simply called semistable. Since this can lead to misunderstandings, the name Nori-semistable has been adopted by several authors.