Abstract
We compute the greatest solutions of systems of linear equations over a lattice (P, ≤). We also present some applications of the results obtained to lattice matrix theory. Let (P, ≤) be a pseudocomplemented lattice with \(\widetilde0\) and \(\widetilde1\) and let A = ‖a ij ‖ n×n , where a ij ∈ P for i, j = 1,..., n. Let A* = ‖a ij ′ ‖ n×n and \( a_{ij} ' = \mathop \Lambda \limits_{r = 1r \ne j}^n a_{ri}^* \) for i, j = 1,..., n, where a* is the pseudocomplement of a ∈ P in (P, ≤). A matrix A has a right inverse over (P, ≤) if and only if A · A* = E over (P, ≤). If A has a right inverse over (P, ≤), then A* is the greatest right inverse of A over (P, ≤). The matrix A has a right inverse over (P, ≤) if and only if A is a column orthogonal over (P, ≤). The matrix D = A · A* is the greatest diagonal such that A is a left divisor of D over (P, ≤).
Invertible matrices over a distributive lattice (P, ≤) form the general linear group GL n (P, ≤) under multiplication. Let (P, ≤) be a finite distributive lattice and let k be the number of components of the covering graph Γ(join(P,≤) − \(\{ \widetilde0\} \), ≤), where join(P, ≤) is the set of join irreducible elements of (P, ≤). Then GL a (P, ≤) ≅ = S n k .
We give some further results concerning inversion of matrices over a pseudocomplemented lattice.
Keywords
Distributive Lattice Orthogonal Matrix Permutation Matrix General Linear Group Great SolutionReferences
- 1.M. Aigner, Combinatorial Theory, Grundlehren Series 234, Springer, New York (1979).MATHGoogle Scholar
- 2.G. Birkhoff, Lattice Theory, AMS, Providence (1967).MATHGoogle Scholar
- 3.G. Gratzer, General Lattice Theory, Akademie, Berlin (1978).Google Scholar
- 4.M. I. Kargapolov and Yu. I. Merzlyakov, Foundations of Group Theory [in Russian], Nauka, Moscow (1972).Google Scholar
- 5.Ki Hang Kim, Boolean Matrix Theory and Applications, Marcel Dekker, New York (1982).MATHGoogle Scholar
- 6.R. D. Luce, “A note on Boolean matrix theory,” Proc. Amer. Math. Soc., 3, No. 2, 382–388 (1952).MATHCrossRefMathSciNetGoogle Scholar
- 7.C. Reutenauer and H. Staubing, “Inversion of matrices over a commutative semiring,” J. Algebra, 88, No. 2, 350–360 (1984).MATHCrossRefMathSciNetGoogle Scholar
- 8.D. E. Rutherford, “Inverses of Boolean matrices,” Proc. Glasgow Math. Assoc., 6, No. 1, 49–53 (1963).MATHMathSciNetCrossRefGoogle Scholar
- 9.L. A. Skornyakov, Elements of Lattice Theory [in Russian], Nauka, Moscow (1970).MATHGoogle Scholar
- 10.L. A. Skornyakov, “Inverses of matrices over a distributive lattice,” Sib. Mat. Zh., 27, No. 2, 182–185 (1986).MATHMathSciNetGoogle Scholar
- 11.L. A. Skornyakov and D. P. Egorova, “Normal subgroups of a general linear group over a distributive lattice,” Algebra Logika, 23, No. 6, 670–683 (1984).MathSciNetGoogle Scholar
- 12.R. P. Stanley, Enumerative Combinatorics, Vol. 1, Wadsworth & Brooks/Cole, Belmont (1986).MATHGoogle Scholar
- 13.J. H. M. Wedderburn, “Boolean linear associative algebra,” Ann. Math., 35, No. 1, 185–194 (1934).CrossRefMathSciNetGoogle Scholar