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Analytic Torsion of Generic Rank Two Distributions in Dimension Five
1Department of Mathematics, University of Vienna, Oskar-Morgenstern-Platz 1, 1090 Vienna, Austria.
Summary
We introduce a new analytic torsion for rank two distributions on 5-manifolds. This torsion aligns with Poincaré duality and finite coverings, offering insights into sub-Riemannian geometry.
Area of Science:
- Differential Geometry
- Geometric Analysis
- Topology
Background:
- Analytic torsion is a key invariant in spectral geometry.
- Rumin complexes are essential for studying differential forms on manifolds with non-smooth structures.
- Rank two distributions on 5-manifolds present complex geometric challenges.
Purpose of the Study:
- To define and analyze a novel analytic torsion for the Rumin complex associated with generic rank two distributions on closed 5-manifolds.
- To investigate the behavior of this torsion under Poincaré duality and finite coverings.
- To establish anomaly formulas relating the torsion to local geometric quantities.
Main Methods:
- Construction of an analytic torsion for the Rumin complex.
- Verification of invariance properties under Poincaré duality and finite coverings.
- Derivation of anomaly formulas using integration of local quantities.
Main Results:
- The proposed analytic torsion is well-defined and exhibits expected behavior under standard geometric transformations.
- Anomaly formulas were established, connecting the torsion to the sub-Riemannian metric and the 2-plane bundle.
- For specific nilmanifolds, the analytic torsion was shown to be equivalent to the Ray-Singer analytic torsion.
Conclusions:
- The developed analytic torsion provides a valuable tool for studying the geometry of rank two distributions.
- The anomaly formulas offer new perspectives on the relationship between global and local invariants in sub-Riemannian geometry.
- The coincidence with Ray-Singer torsion for nilmanifolds validates the proposed invariant and suggests broader connections.
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