# The Invar tensor package: Differential invariants of Riemann

## Description

Abstract The long standing problem of the relations among the scalar invariants of the Riemann tensor is computationally solved for all 6 ṡ 10 ^(23)objects with up to 12 derivatives of the metric. This covers cases ranging from products of up to 6 undifferentiated Riemann tensors to cases with up to 10 covariant derivatives of a single Riemann. We extend our computer algebra system Invar to produce within seconds a canonical form for any of those objects in terms of a basis.... Title of program: Invar Tensor Package v2.0 Catalogue Id: ADZK_v2_0 Nature of problem Manipulation and simplification of scalar polynomial expressions formed from the Riemann tensor and its covariant derivatives. Versions of this program held in the CPC repository in Mendeley Data ADZK_v1_0; Invar Tensor Package; 10.1016/j.cpc.2007.05.015 ADZK_v2_0; Invar Tensor Package v2.0; 10.1016/j.cpc.2008.04.018 This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2019)