English
Related papers

Related papers: Complete positivity and self-adjointness

200 papers

We study quantum processes, as one parameter families of differentiable completely positive and trace preserving (CPTP) maps. Using different representations of the generator, and the Sylvester criterion for positive semi-definite matrices,…

Quantum Physics · Physics 2019-09-17 Gustavo Montes Cabrera , David Davalos , Thomas Gorin

To each of the symmetry groups of the Platonic solids we adjoin a carefully designed involution yielding topological generators of PU(2) which have optimal covering properties as well as efficient navigation. These are a consequence of…

Number Theory · Mathematics 2018-04-11 Ori Parzanchevski , Peter Sarnak

We introduce the concept of completely positive roots of completely positive maps on operator algebras. We do this in different forms: as asymptotic roots, proper discrete roots and as continuous one-parameter semigroups of roots. We…

Operator Algebras · Mathematics 2020-04-21 B. V. Rajarama Bhat , Robin Hillier , Nirupama Mallick , Vijaya Kumar U

In this paper the Jessen's type inequality for normalized positive $C_0$-semigroups is obtained. An adjoint of Jessen's type inequality has also been derived for the corresponding adjoint-semigroup, which does not give the analogous results…

Functional Analysis · Mathematics 2015-04-08 Gul I hina Aslam , Matloob Anwar

A new construction for the form sum of positive, selfadjoint operators is given in this paper. The situation is a bit more general, because our aim is to add positive, symmetric operators. With the help of the used method, some commutation…

Functional Analysis · Mathematics 2007-05-23 Balint Farkas , Mate Matolcsi

We give a new and very short proof of a theorem of Greiner asserting that a positive and contractive $C_0$-semigroup on an $L^p$-space is strongly convergent in case that it has a strictly positive fixed point and contains an integral…

Functional Analysis · Mathematics 2017-06-06 Moritz Gerlach , Jochen Glück

Kolmogorov decomposition for a given completely positive definite kernel is a generalization of Paschke's GNS construction for the completely positive map. Using Kolmogorov decomposition, to every quantum dynamical semigroup (QDS) for…

Operator Algebras · Mathematics 2025-01-17 Santanu Dey , Dimple Saini , Harsh Trivedi

A symmetric tensor, which has a symmetric nonnegative decomposition, is called a completely positive tensor. We consider the completely positive tensor decomposition problem. A semidefinite algorithm is presented for checking whether a…

Optimization and Control · Mathematics 2014-11-20 Jinyan Fan , Anwa Zhou

We consider perturbations of dynamical semigroups on the algebra of all bounded operators in a Hilbert space generated by covariant completely positive measures on the semi-axis. The construction is based upon unbounded linear perturbations…

Quantum Physics · Physics 2021-01-06 G. G. Amosov

We generalize the result of Gorini, Kossakowski, and Sudarshan [J. Math. Phys. 17:821, 1976] that every generator of a quantum-dynamical semigroup decomposes uniquely into a closed and a dissipative part, assuming the trace of both…

Quantum Physics · Physics 2024-07-04 Frederik vom Ende

We give an explicit set of generators for the semigroup of the Gr\"obner degeneration of a toric ideal. This set of generators is used to study algebraic properties of the semigroup it generates: approximation of semigroups,…

Commutative Algebra · Mathematics 2023-04-07 Hernán de Alba Casillas , Daniel Duarte , Raúl Vargas Antuna

In this article we revisit a new notion of positivity in real semisimple Lie groups that at the same time generalizes total positivity in split real Lie groups as well as positive Lie semigroups in Hermitian Lie groups of tube type. We…

Group Theory · Mathematics 2025-11-18 Anna Wienhard

We study self-adjoint semigroups of partial isometries on a Hilbert space. These semigroups coincide precisely with faithful representations of abstract inverse semigroups. Groups of unitary operators are specialized examples of…

Functional Analysis · Mathematics 2013-06-13 Alexey I. Popov , Heydar Radjavi

We study automaton structures, i.e. groups, monoids and semigroups generated by an automaton, which, in this context, means a deterministic finite-state letter-to-letter transducer. Instead of considering only complete automata, we…

Formal Languages and Automata Theory · Computer Science 2020-07-17 Daniele D'Angeli , Emanuele Rodaro , Jan Philipp Wächter

We give canonical forms of selfadjoint and isometric operators on a complex vector space $U$ with scalar product given by a positive semidefinite Hermitian form, and of Hermitian forms on $U$. For an arbitrary system of semiunitary spaces…

Representation Theory · Mathematics 2020-12-29 Victor A. Bovdi , Tetiana Klymchuk , Tetiana Rybalkina , Mohamed A. Salim , Vladimir V. Sergeichuk

Quantum stochastic cocycles provide a basic model for time-homogeneous Markovian evolutions in a quantum setting, and a direct counterpart in continuous time to quantum random walks, in both the Schrodinger and Heisenberg pictures. This…

Functional Analysis · Mathematics 2021-03-31 J. Martin Lindsay , Stephen J. Wills

We give a self-contained and streamlined exposition of a generation theorem for C0-semigroups based on the method of boundary triplets. We apply this theorem to port-Hamiltonian systems where we discuss recent results appearing in stability…

Functional Analysis · Mathematics 2020-05-26 Sven-Ake Wegner

Let G be a connected reductive group over the complex numbers with a fixed pinning. We define and study the totally positive part of the set of maximal tori of G.

Representation Theory · Mathematics 2024-11-11 G. Lusztig

In this paper we prove that every automorphism of the semigroup of invertible matrices with nonnegative elements over a linearly oredered associative ring on some specially defined subgroup concides with the composition of an inner…

Rings and Algebras · Mathematics 2007-05-23 Elena I. Bunina , Alexandr V. Mikhalev

In this short note, we are interested in discussing characteristics of finite generating sets for $\mathcal{F}$, the set of all semiflows with non negative coefficients of a Petri Net. By systematically positioning these results over semi…

Formal Languages and Automata Theory · Computer Science 2023-02-06 Gerard Memmi