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Measures Invariant under the Geodesic Flow and their Projections

Craig J. Sutton
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Abstract

Let $S^{n}$ be the $n$-sphere of constant positive curvature. For $n \geq 2$, we will show that a measure on the unit tangent bundle of $S^{2n}$, which is even and invariant under the geodesic flow, is not uniquely determined by its projection to $S^{2n}$.

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Craig J. Sutton. 2003-02-06. Measures Invariant under the Geodesic Flow and their Projections. https://arxiv.org/abs/math/0302072

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