Arithmetic Aspects of Weil Bundles over $p$-Adic Manifolds
S. Tchuiaga, C. Dor Kewir
TL;DR
The paper develops a systematic theory of Weil bundles $M^A$ over $p$-adic analytic manifolds to encode infinitesimal deformations in a non-archimedean setting. It constructs $M^A$ as a $p$-adic analytic space, proves lifting theorems for analytic functions, vector fields, forms, and connections, and shows a Galois-equivariant structure when $M$ is defined over a number field. A cohomological comparison is established, linking $H^k_{ ext{dR}}(M^A/ obreak\mathbb{Q}_p)$ with crystalline cohomology via $H^k_{ ext{crys}}(M/ obreak\mathbb{Z}_p) ens A$, thereby connecting infinitesimal geometry to $p$-adic Hodge theory. The framework yields applications to $p$-adic modular forms, Diophantine geometry, and infinitesimal solutions on elliptic curves, offering a geometric lens for deformation theory in the arithmetic context.
Abstract
We introduce a systematic theory of Weil bundles over \( p \)-adic analytic manifolds, forging new connections between differential calculus over non-archimedean fields and arithmetic geometry. By developing a framework for infinitesimal structures in the \( p \)-adic setting, we establish that Weil bundles \( M^A \) associated with a \( p \)-adic manifold \( M \) and a Weil algebra \( A \) inherit a canonical analytic structure. Key results include: \text{Lifting theorems :} for analytic functions, vector fields, and connections, enabling the transfer of geometric data from \( M \) to \( M^A \). A \text{Galois-equivariant structure :} on Weil bundles defined over number fields, linking their geometry to arithmetic symmetries. A \text{cohomological comparison isomorphism:} between the Weil bundle \( M^A \) and the crystalline cohomology of \( M \), unifying infinitesimal and crystalline perspectives. Applications to Diophantine geometry and \( p \)-adic Hodge theory are central to this work. We show that spaces of sections of Hodge bundles on \( M^A \) parametrize \( p \)-adic modular forms, offering a geometric interpretation of deformation-theoretic objects. Furthermore, Weil bundles are used to study infinitesimal solutions of equations on elliptic curves, revealing new structural insights into \( p \)-adic deformations.
