8 papers
On unconventional discretisations
Basil Grammaticos, Thamizharasi Tamizhmani, Ralph Willox
We present various discretisation techniques that mark a departure from the classical algorithms of numerical analysis, in the aim of preserving the physical behaviour of the solut…
Singularity interactions for lattice equations: introducing the taishi
Ralph Willox, Basil Grammaticos, Alfred Ramani +1
We study the singularities of some selected integrable lattice equations and show they all admit three types of singularities: one of finite and two of infinite extent. In particul…
A simple strategy for constructing ultradiscrete systems that exhibit the same dynamics as a given continuous model
Ralph Willox
Over the past 30 years, the special limiting procedure known as ultradiscretisation has become the tool of choice in the field of infinite dimensional integrable systems for constr…
Deautonomising the Lyness mapping
Basil Grammaticos, Alfred Ramani, Ralph Willox
We examine the Lyness mapping (an integrable th-order discrete system which can be generated from a one-dimensional reduction of the Hirota-Miwa equation) from the point of view…
The trouble with deautonomising higher order maps
Ralph Willox, Basil Grammaticos, Alfred Ramani
The deautonomisation of birational maps that have the singularity confinement property, i.e. the construction of nonautonomous versions of such maps that preserve the singularity p…
What is the symmetry group of a d- discrete Painlevé equation?
Anton Dzhamay, Yang Shi, Alexander Stokes +1
The symmetry group of a (discrete) Painlevé equation provides crucial information on the properties of the equation. In this paper we argue against the commonly-held belief that t…