In ‎this ‎paper, ‎we ‎study ‎the ‎relation ‎between ‎the ‎soft ‎sets ‎and ‎soft ‎Lie ‎algebras ‎with ‎the ‎lattice theory. ‎We ‎introduce ‎the ‎concepts ‎of ‎the ‎lattice ‎of ‎soft ‎sets, ‎full ‎soft ‎sets ‎and ‎soft ‎Lie ‎algebras ‎and next, we ‎verify ‎some ‎properties ‎of ‎them. We ‎prove ‎that ‎the ‎lattice ‎of ‎the ‎soft ‎sets ‎on ‎a fixed parameter set is isomorphic to the power set of a ...

We prove complete reducibility for an integrable module for an affine Lie algebra where the canonical central element acts non-trivially. We further prove that integrable modules does not exists for most of the super affine Lie algebras where the center acts non-trivially. 1 2000 Mathematics subject classification primary 17B65, 17B68

In this paper, we discuss the pair problem of generators in affine Kac-Moody Lie algebras. For any affine Kac-Moody algebra g(A) of X l type and arbitrary nonzero imaginary root vector x, we prove that there exists some y ∈ g(A), such that g′(A) is contained in the Lie algebra generated by x and y.

The Nagano-Yagi-Goldmann theorem states that on the torus T, every affine (or projective) structure is invariant or is constructed on the basis of some Goldmann rings [N-Y]. It shows the interest to study the invariant affine structure on the torus T or on abelian Lie groups. Recently, the works of Kim [K] and Dekempe-Ongenae [D-O] precise the number of non equivalent invariant affine structure...

We study the problem of matrix Lie algebra conjugacy. Lie algebras arise centrally in areas as diverse as differential equations, particle physics, group theory, and the Mulmuley–Sohoni Geometric Complexity Theory program. A matrix Lie algebra is a set L of matrices such that M1,M2 ∈ L =⇒ M1M2 − M2M1 ∈ L. Two matrix Lie algebras are conjugate if there is an invertible matrix M such that L1 = ML...

We say that an indecomposable Cartan matrix A with entries in the ground field of characteristic 0 is almost affine if Lie sub(super)algebra determined by it not finite dimensional or but (super)algebra any submatrix A, obtained striking out row and column intersecting on main diagonal, sum (super)algebras. said to be affine, all its matrices are affine. list superalgebras over complex numbers ...

We give uniform formulas for the branching rules of level 1 modules over orthogonal affine Lie algebras for all conformal pairs associated to symmetric spaces. We also provide a combinatorial intepretation of these formulas in terms of certain abelian subalgebras of simple Lie algebras.

We establish several results regarding the algebra of derivations of tensor product of two algebras, and its connection to finite order automorphisms. These results generalize some well-know theorems in the literature. Dedicated to Professor Bruce Allison on the occasion of his sixtieth birthday 0. Introduction In 1969, R. E. Block [B] showed that the algebra of derivations of tensor product of...

A complete classification of the WZNW modular invariant partition functions is known for very few affine algebras and levels, the most significant being all levels of SU(2), and level 1 of all simple algebras. In this paper we solve the classification problem for SU(3) modular invariant partition functions. Our approach will also be applicable to other affine Lie algebras, and we include some p...