Quantum operationIn quantum mechanics, a quantum operation (also known as quantum dynamical map or quantum process) is a mathematical formalism used to describe a broad class of transformations that a quantum mechanical system can undergo. This was first discussed as a general stochastic transformation for a density matrix by George Sudarshan. The quantum operation formalism describes not only unitary time evolution or symmetry transformations of isolated systems, but also the effects of measurement and transient interactions with an environment.
Théorie des perturbationsLa théorie des perturbations est un domaine des mathématiques, qui consiste à étudier les contextes où il est possible de trouver une solution approchée à une équation en partant de la solution d'un problème plus simple. Plus précisément, on cherche une solution approchée à une équation (E) (dépendante d'un paramètre λ), sachant que la solution de l'équation (E) (correspondant à la valeur λ=0) est connue exactement. L'équation mathématique (E) peut être par exemple une équation algébrique ou une équation différentielle.
LindbladianIn quantum mechanics, the Gorini–Kossakowski–Sudarshan–Lindblad equation (GKSL equation, named after Vittorio Gorini, Andrzej Kossakowski, George Sudarshan and Göran Lindblad), master equation in Lindblad form, quantum Liouvillian, or Lindbladian is one of the general forms of Markovian master equations describing open quantum systems. It generalizes the Schrödinger equation to open quantum systems; that is, systems in contacts with their surroundings.
Topological tensor productIn mathematics, there are usually many different ways to construct a topological tensor product of two topological vector spaces. For Hilbert spaces or nuclear spaces there is a simple well-behaved theory of tensor products (see Tensor product of Hilbert spaces), but for general Banach spaces or locally convex topological vector spaces the theory is notoriously subtle. One of the original motivations for topological tensor products is the fact that tensor products of the spaces of smooth functions on do not behave as expected.
Spinors in three dimensionsIn mathematics, the spinor concept as specialised to three dimensions can be treated by means of the traditional notions of dot product and cross product. This is part of the detailed algebraic discussion of the rotation group SO(3). The association of a spinor with a 2×2 complex Hermitian matrix was formulated by Élie Cartan. In detail, given a vector x = (x1, x2, x3) of real (or complex) numbers, one can associate the complex matrix In physics, this is often written as a dot product , where is the vector form of Pauli matrices.
