Brajerčík, Ján Second order differential invariants of linear frames. (English) Zbl 1220.53018 Balkan J. Geom. Appl. 15, No. 2, 14-25 (2010). The aim of this paper is to characterize all second order tensor-valued and scalar differential invariants of the bundle of linear frames \(FX\) over an \(n\)-dimensional manifold \(X\). These differential invariants are obtained by factorization method and are described in terms of bases of invariants. Second order natural Lagrangians of frames have been characterized explicitly; if \(n=1, 2, 3, 4\), the number of functionally independent second order natural Lagrangians is \(N=0, 6, 33, 104\), respectively. Reviewer: Radu Miron (Iaşi) MSC: 53A55 Differential invariants (local theory), geometric objects 58A10 Differential forms in global analysis 58A20 Jets in global analysis 58A32 Natural bundles 16W22 Actions of groups and semigroups; invariant theory (associative rings and algebras) Keywords:frame; differential invariant; equivariant mapping; differential group; natural Lagrangian PDFBibTeX XMLCite \textit{J. Brajerčík}, Balkan J. Geom. Appl. 15, No. 2, 14--25 (2010; Zbl 1220.53018) Full Text: EuDML