Results 1 to 10 of about 14,182 (265)
On families of twisted power partial isometries
We consider families of power partial isometries satisfying twisted commutation relations with deformation parameters $\lambda_{ij}\in\mathbb C$, $|\lambda_{ij}|=1$.
V.L. Ostrovskyi +2 more
doaj +1 more source
Detecting mixed-unitary quantum channels is NP-hard [PDF]
A quantum channel is said to be a $\textit{mixed-unitary}$ channel if it can be expressed as a convex combination of unitary channels. We prove that, given the Choi representation of a quantum channel $\Phi$, it is NP-hard with respect to polynomial-time
Colin Do-Yan Lee, John Watrous
doaj +1 more source
Transfer of Unitary Representations [PDF]
In the present paper, the authors explain and give applications of the notion of transfer between real forms of a semi-simple Lie group \(G^{\mathbb C}\) over \(\mathbb C\), which first appeared in [\textit{N. R. Wallach}, Contemp. Math. 177, 181--216 (1994; Zbl 0833.22021)]. The main idea is that some representation of a real form of \(G^{\mathbb C}\)
Wallach, Nolan R., Zhu, Chen-Bo
openaire +2 more sources
Representation Matching For Remote Quantum Computing
Many quantum computational tasks have inherent symmetries, suggesting a path to enhancing their efficiency and performance. Exploiting this observation, we propose representation matching, a generic probabilistic protocol for reducing the cost of quantum
Yuxiang Yang, Masahito Hayashi
doaj +1 more source
Algebras Generated by Finite Subgroups of Unitary Groups
Group representation theory is one of the most powerful tools to study groups. The unitary group is an important research branch of group theories. We study a class of algebraic structures generated by unitary groups,and we prove that Alg( H) is a von ...
LUO Lai-zhen, LI Xing-hua, TAO Yuan-hong
doaj +1 more source
On Constructing Informationally Complete Covariant Positive Operator-Valued Measures
We study a projective unitary representation of the product G=G˜×G, where G is a locally compact Abelian group and G^ is its dual consisting of characters on G.
Grigori Amosov
doaj +1 more source
Topological Boundaries of Unitary Representations [PDF]
AbstractWe introduce and study a generalization of the notion of the Furstenberg boundary of a discrete group $\Gamma $ to the setting of a general unitary representation $\pi : \Gamma \to B(\mathcal H_\pi )$. This space, which we call the “Furstenberg–Hamana boundary” (or "FH-boundary") of the pair $(\Gamma , \pi )$, is a $\Gamma $-invariant subspace ...
Bearden, Alex, Kalantar, Mehrdad
openaire +2 more sources
A note on cocycles of unitary representations [PDF]
Given a unitary representation U U of a locally compact abelian group
Parry, W., Schmidt, K.
openaire +1 more source
Tight Representations of 0-𝐸-Unitary Inverse Semigroups
We study the tight representation of a semilattice in {0,1} by some examples. Then we introduce the concept of the complex tight representation of an inverse semigroup 𝑆 by the concept of the tight representation of the semilattice of idempotents 𝐸 of 𝑆 ...
Bahman Tabatabaie Shourijeh +1 more
doaj +1 more source
The unitary representations of the Poincar\'e group in any spacetime dimension
An extensive group-theoretical treatment of linear relativistic field equations on Minkowski spacetime of arbitrary dimension $D\geqslant 3$ is presented.
Xavier Bekaert, Nicolas Boulanger
doaj +1 more source

