Results 51 to 60 of about 9,623 (179)

Enlarged symmetry algebras of spin chains, loop models, and S-matrices

, 2007
The symmetry algebras of certain families of quantum spin chains are considered in detail. The simplest examples possess m states per site (m\geq2), with nearest-neighbor interactions with U(m) symmetry, under which the sites transform alternately along ...
Affleck, Anderson, Bakalov, Barber, Baxter, Carter, Chari, di Francesco, Di Francesco, Dipper, Dipper, Du, Erdmann, Fendley, Freedman, Goodman, Goodman, Graham, Gruzberg, Gurarie, H. Saleur, Hardy, Jacobsen, Jones, Jones, Jones, Kassel, Koo, Koo, König, König, Larsen, Mann, Mann, Martin, Martin, Martin, Martin, Martin, Martin, Martin, Mathas, N. Read, Nienhuis, Nienhuis, Pasquier, Pierce, Read, Read, Ringel, Sagan, Saleur, Temperley, Turaev   +53 more
core   +1 more source

Boundary representations of locally compact hyperbolic groups

Proceedings of the London Mathematical Society, Volume 131, Issue 6, December 2025.
Abstract We develop the theory of Patterson–Sullivan measures for locally compact hyperbolic groups. This theory associates to certain left‐invariant metrics on the group measures on its boundary. Next, we establish irreducibility of the resulting (unitary) Koopman representations for second countable, nonelementary, unimodular locally compact ...
Michael Glasner
wiley   +1 more source

Optimal solutions to matrix-valued Nehari problems and related limit theorems

, 2011
In a 1990 paper Helton and Young showed that under certain conditions the optimal solution of the Nehari problem corresponding to a finite rank Hankel operator with scalar entries can be efficiently approximated by certain functions defined in terms of ...
AE Frazho, AE Frazho, BA Francis, C Foias, C Foias, C Foias, D Sarason, H Bart, I Gohberg, I Gohberg, JW Helton, MJ Corless, S Horst ter, S Horst ter, VM Adamjan, VV Peller   +15 more
core   +2 more sources

Local spectral theory for subordinated operators: The Cesàro operator and beyond

Journal of the London Mathematical Society, Volume 112, Issue 2, August 2025.
Abstract We study local spectral properties for subordinated operators arising from C0$C_0$‐semigroups. Specifically, if T=(Tt)t⩾0$\mathcal {T}=(T_t)_{t\geqslant 0}$ is a C0$C_0$‐semigroup acting boundedly on a complex Banach space and Hν=∫0∞Ttdν(t)$$\begin{equation*} \mathcal {H}_\nu = \int _{0}^{\infty } T_t\; d\nu (t) \end{equation*}$$is the ...
Eva A. Gallardo‐Gutiérrez, F. Javier González‐Doña   +1 more
wiley   +1 more source

The q-Higgs and Askey–Wilson algebras

Nuclear Physics B, 2019
A q-analogue of the Higgs algebra, which describes the symmetry properties of the harmonic oscillator on the 2-sphere, is obtained as the commutant of the oq1/2(2)⊕oq1/2(2) subalgebra of oq1/2(4) in the q-oscillator representation of the quantized ...
Luc Frappat, Julien Gaboriaud, Eric Ragoucy, Luc Vinet   +3 more
doaj   +1 more source

Non-Polynomial Realizations of W-Algebras

, 1995
Relaxing first-class constraint conditions in the usual Drinfeld-Sokolov Hamiltonian reduction leads, after symmetry fixing, to realizations of W algebras expressed in terms of all the J-current components.
Barbarin, F., Ragoucy, E., Sorba, P.
core   +1 more source

Linear independence of coherent systems associated to discrete subgroups

Bulletin of the London Mathematical Society, Volume 57, Issue 2, Page 315-329, February 2025.
Abstract This note considers the finite linear independence of coherent systems associated to discrete subgroups. We show by simple arguments that such coherent systems of amenable groups are linearly independent whenever the associated twisted group ring does not contain any nontrivial zero divisors.
Ulrik Enstad, Jordy Timo van Velthoven
wiley   +1 more source

Euler characteristics of affine ADE Nakajima quiver varieties via collapsing fibres

Journal of the London Mathematical Society, Volume 111, Issue 2, February 2025.
Abstract We prove a universal substitution formula that compares generating series of Euler characteristics of Nakajima quiver varieties associated with affine ADE diagrams at generic and at certain non‐generic stability conditions via a study of collapsing fibres in the associated variation of GIT map, unifying and generalising earlier results of the ...
Lukas Bertsch, Ádám Gyenge, Balázs Szendrői   +2 more
wiley   +1 more source

Derivations and Extensions in JC‐Algebras

International Journal of Mathematics and Mathematical Sciences, Volume 2025, Issue 1, 2025.
A well‐known result by Upmeier states that every derivation on a universally reversible JC‐algebra A⊆B(H)sa extends to the C∗‐algebra [A] generated by A in B(H). In this paper, we significantly strengthen this result by proving that every Jordan derivation on a universally reversible JC‐algebra A extends to ∗‐derivations on its universal enveloping ...
Fatmah B. Jamjoom, Doha A. Abulhamail, Armando Sánchez-Nungaray   +2 more
wiley   +1 more source

Exhaustive Characterization of Quantum Many-Body Scars Using Commutant Algebras

Physical Review X
We study quantum many-body scars (QMBS) in the language of commutant algebras, which are defined as symmetry algebras of families of local Hamiltonians.
Sanjay Moudgalya, Olexei I. Motrunich
doaj   +1 more source