On linear programming and matrix scaling over the algebraic numbers

Abstract

Adler and Beling considered the linear programming problem over the real algebraic numbers. They obtained the necessary bounds in terms of a notion of size and dimension needed to justify its polynomial-time solvability, using the ellipsoid method and under some models of computation. Based on a better notion of size than that used by Adler and Beling, we first reduce the feasibility problem in linear programming to some canonical problems preserving its size and its constraint-matrix dimensions. For these canonical problems as well as for the matrix scaling problem, shown to be a more general problem than linear programming, we obtain the necessary bounds; demonstrate simple rounding schemes; justify the applicability of two polynomial-time interior-point algorithms under some models of computation; describe a method for solving a system of linear equations over the algebraic numbers which is a subroutine within these interior-point algorithms under an input model; and give an alternative method to the traditional duality-based approach for the conversion of a general linear programming problem into a feasibility problem.