English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We apply E. Cartan's method of equivalence to classify 7-dimensional,2-nondegenerate CR manifolds $M$ up to local CR equivalence in the case thatthe cubic form of $M$ satisfies a certain symmetry property with respect to theLevi form of $M$. The solution to the equivalence problem is given by aparallelism on a principal bundle over $M$. When the nondegenerate part of theLevi form has definite signature, the parallelism takes values in$\mathfrak{su}(2,2)$. When this signature is split and an additional"isotropy-switching" hypothesis is satisfied, the parallelism takes values in$\mathfrak{su}(3,1)$. Differentiating the parallelism provides a complete setof local invariants of $M$. We exhibit an explicit example of a realhypersurface in $\mathbb{C}^4$ whose invariants are nontrivial.

The Local Equivalence Problem for 7-Dimensional, 2-Nondegenerate CR Manifolds whose Cubic Form is of Conformal Unitary Type