Tori biyu na iya raba local geometry iri ɗaya amma har yanzu su zama siffofi daban
Wata construction a Publications mathematiques de l’IHES ta ba da compact Bonnet pairs na farko: smooth, real-analytic tori biyu a sararin dimensions uku da ke da intrinsic metric da mean curvature iri ɗaya a corresponding points, amma ba siffa ɗaya ba ne har zuwa rigid motion. Sakamakon ya rufe tsoffin tambayoyin uniqueness a surface geometry kuma counterexample ne mai tsabta ga tunanin cewa isassun local measurements dole su uniquely gane compact shape.