We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.
To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure [email protected]
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Reconstructing a $d$-polytope from its $k$-skeleton ($k\le d-2$) amounts to determining the face lattice of the polytope from the dimension and skeleton. For each $d\ge 4$, there are $d$-polytopes that have isomorphic $(d-3)$-skeleta and yet are not combinatorially isomorphic. But every $d$-polytope is reconstructible from its $(d-2)$-skeleton. Section 5.2 focusses on reconstructions from 2-skeletons and 1-skeletons. It presents an algorithm that reconstructs a $d$-polytope with at most $d-2$ nonsimple vertices from its dimension and 2-skeleton. This result is tight: there are pairs of nonisomorphic $d$-polytopes with $d-1$ nonsimple vertices and isomorphic $(d-3)$-skeleta for each $d\ge 4$.Blind and Mani-Levitska (1987), and later Kalai (1988), showed that a simple polytope can be reconstructed from its dimension and graph. We present a slight generalisation of this result and briefly discuss the theorem of Friedman (2009) stating that the reconstruction can be done in time polynomial in the number of vertices. The chapter ends with variations on the reconstruction problem.
Recommend this
Email your librarian or administrator to recommend adding this to your organisation's collection.