stoquastic /stəˈkwæstɪk/ adjective1 •Of a Hermitian matrix, having real non-positive off-diagonal elements. These matrices have elements of quantum mechanics and classical theory of stochastic matrices. For non-technical purposes ‘stoquastic’ is equivalent to “avoiding the sign problem”.Stoquastic Hamiltonians, those for which all off-diagonal matrix elements in the standard basis are real and non-positive, are common in the physical world. — 2015
