- positive semidefinite operator
- положительно полуопределённый оператор
English-Russian scientific dictionary. 2008.
English-Russian scientific dictionary. 2008.
Positive-definite matrix — In linear algebra, a positive definite matrix is a matrix that in many ways is analogous to a positive real number. The notion is closely related to a positive definite symmetric bilinear form (or a sesquilinear form in the complex case). The… … Wikipedia
Choi's theorem on completely positive maps — In mathematics, Choi s theorem on completely positive maps (after Man Duen Choi) is a result that classifies completely positive maps between finite dimensional (matrix) C* algebras. An infinite dimensional algebraic generalization of Choi s… … Wikipedia
Contraction (operator theory) — In operator theory, a bounded operator T: X → Y between normed vector spaces X and Y is said to be a contraction if its operator norm ||T|| ≤ 1. Every bounded operator becomes a contraction after suitable scaling. The analysis of… … Wikipedia
Square root of a matrix — In mathematics, the square root of a matrix extends the notion of square root from numbers to matrices. A matrix B is said to be a square root of A if the matrix product B · B is equal to A.[1] Contents 1 Properties 2 Computation methods … Wikipedia
POVM — In functional analysis and quantum measurement theory, a POVM (Positive Operator Valued Measure) is a measure whose values are non negative self adjoint operators on a Hilbert space. It is the most general formulation of a measurement in the… … Wikipedia
Cholesky decomposition — In linear algebra, the Cholesky decomposition or Cholesky triangle is a decomposition of a Hermitian, positive definite matrix into the product of a lower triangular matrix and its conjugate transpose. It was discovered by André Louis Cholesky… … Wikipedia
Polar decomposition — In mathematics, particularly in linear algebra and functional analysis, the polar decomposition of a matrix or linear operator is a factorization analogous to the polar form of a nonzero complex number z where r is the absolute value of z (a… … Wikipedia
Density matrix — Mixed state redirects here. For the psychiatric condition, see Mixed state (psychiatry). In quantum mechanics, a density matrix is a self adjoint (or Hermitian) positive semidefinite matrix (possibly infinite dimensional) of trace one, that… … Wikipedia
Eigenvalues and eigenvectors — For more specific information regarding the eigenvalues and eigenvectors of matrices, see Eigendecomposition of a matrix. In this shear mapping the red arrow changes direction but the blue arrow does not. Therefore the blue arrow is an… … Wikipedia
List of numerical analysis topics — This is a list of numerical analysis topics, by Wikipedia page. Contents 1 General 2 Error 3 Elementary and special functions 4 Numerical linear algebra … Wikipedia
Mercer's theorem — In mathematics, specifically functional analysis, Mercer s theorem is a representation of a symmetric positive definite function on a square as a sum of a convergent sequence of product functions. This theorem, presented in (Mercer 1909), is one… … Wikipedia