In this paper we describe a C++ implementation of a hybrid system combining SLI (symmetric level-index) arithmetic and FLP (floating-point) arithmetic. The principal motivation for the work to be presented is to promote the use of SLI arithmetic as a practical framework for scientific computing. This hybrid arithmetic is essentially overflow and underflow free, and its implementation has shown ...

Motivated by an application to LDPC (low density parity check) algebraic geometry codes described by Voloch and Zarzar, we describe a computational procedure for establishing an upper bound on the arithmetic or geometric Picard number of a smooth projective surface over a finite field, by computing the Frobenius action on p-adic cohomology to a small degree of p-adic accuracy. We have implement...

Transforming geometric algorithms into effective computer programs is a difficult task. This transformation is particularly made hard by the basic assumptions of most theoretical geometric algorithms concerning the handling of robustness issues, namely issues related to arithmetic precision and degenerate input. We start with a discussion of the gap between the theory and practice of geometric ...

In 1983 Takeuchi showed that up to conjugation there are exactly 4 arithmetic subgroups of PSL2(R) with signature (1;∞). Shinichi Mochizuki gave a purely geometric characterization of the corresponding arithmetic (1;∞)-curves, which also arise naturally in the context of his recent work on inter-universal Teichmüller theory. Using Bely̆ı maps, we explicitly determine the canonical models of thes...