A Bound for the Radius of a Tight Ball in a Contact Metric 3-manifold
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چکیده
We establish a bound for the radius of a tight ball in a, not necessarily closed, contact 3-manifold (M, ξ). The bound is calculated with respect to a Riemannian metric g compatible with an associated contact form α and an almost complex structure on ξ (see [2, 4]). We also consider a weaker form of compatibility and derive similar bounds in this context. In particular we give a Riemannian geometric condition that implies a contact structure is universally tight.
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تاریخ انتشار 2009