The unimodularity of the induced toric tilings
V. G. Zhuravlevab a Steklov Mathematical Institute of Russian Academy of Sciences, Moscow, Russia
b Vladimir State University, Vladimir, Russia
Abstract:
Induced tilings
$\mathcal T=\mathcal T|_\mathrm{Kr}$ of the
$d$-dimensional torus
$\mathbb T^d$, generated by the embedded karyon
$\mathrm{Kr}$, are considered. The operations of differentiation are defined
$\sigma\colon\mathcal T\to\mathcal T^\sigma$, as a result we get again induced partitions $\mathcal T^\sigma=\mathcal T|_{\mathrm{Kr}^\sigma}$ of the same torus
$\mathbb T^d$, generated by the derived karyon
$\mathrm{Kr}^\sigma$. In the language of the karyons
$\mathrm {Kr}$ the derivations of
$\sigma$ reduce to a combination of geometric transformations of the space
$\mathbb R^d$. It is proved that if the karyon
$\mathrm{Kr}$ is unimodular, then it generates an induced tiling
$\mathcal T=\mathcal T|_\mathrm{Kr}$ and the derivative karyon
$\mathrm{Kr}^\sigma$ is unimodular again. So there exists the corresponding derivative tiling $\mathcal T^\sigma=\mathcal T|_{\mathrm {Kr}^\sigma}$. Using unimodular karyons one can build an infinite family of induced tilings
$\mathcal T=\mathcal T(\alpha,\mathrm{Kr}_*)$ depending on a shift vector
$\alpha$ of the torus
$\mathbb T^d$ and the initial karyon
$\mathrm{Kr}_*$. Two algorithms are presented for constructing such unimodular karyons of
$\mathrm{Kr}_*$.
Key words and phrases:
shift vector, induced tilings, induced toric tilings, oblique shift, derived karyon, exchange transformation of a torus, derived tilings, contraction along a straight line.
UDC:
511.3
Received: 08.02.2018