Geometric uncertainty principles for Schr\"odinger evolutions on negatively curved manifolds

TL;DR

This paper extends the classical uncertainty principle for Schr"odinger equations to negatively curved manifolds, revealing a rigidity phenomenon influenced by hyperbolic geometry.

Contribution

It develops new Carleman estimates and logarithmic convexity results for Schr"odinger evolutions on hyperbolic manifolds, overcoming the lack of translation invariance.

Findings

Rigidity phenomenon persists in hyperbolic geometry despite geometric differences.

New Carleman estimates and logarithmic convexity are established for curved spaces.

Curvature significantly influences the uniqueness properties of dispersive equations.

Abstract

In this paper, we study the uncertainty principle for Schr\"odinger equations with a bounded time-independent potentials on certain Cartan-Hadamard manifolds endowed with an asymptotic hyperbolic metric in dimensions $n\geq2$. The classical Hardy uncertainty principle in Euclidean space, as developed in the works of Escauriaza-Kenig-Ponce-Vega (JEMS, 2008; Duke Math. J., 2010), reveals a rigidity phenomenon for solution $u$ to Schr\"odinger equations: sufficiently strong Gaussian decay at two distinct times yields $u\equiv0$. In this work, we show that a similar rigidity persists in the setting of hyperbolic geometry, despite the absence of translation invariance and Fourier representation. Our approach follows a general strategy of Escauriaza-Kenig-Ponce-Vega, where the underlying geometry brings an essential change. This enables us to establish new Carleman estimates and logarithmic convexity. Unlike the Euclidean setting, the hyperbolic geometry exhibits exponential volume growth and nontrivial geodesic escape at infinity, which fundamentally alters the propagation mechanism of Schr\"odinger evolutions. Based on the newly-built virial identities and an approximation argument, we derive the logarithmic convexity. The main difficulty in proving the logarithmic convexity is the lack of convolution structure on general manifolds. By making use of the exponential map and Jacobi field, we define a new mollifier on curved geometry. Meanwhile, to establish the Carleman estimate adapted to hyperbolic space, we introduce a new weight function adapted to the curved manifold. Our results highlight the role of curvature in shaping quantitative uniqueness properties for dispersive equations.