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Related papers: Geometry of quantum systems: density states and en…

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Computational complexity is a new quantum information concept that may play an important role in holography and in understanding the physics of the black hole interior. We consider quantum computational complexity for $n$ qubits using…

High Energy Physics - Theory · Physics 2021-05-21 Roberto Auzzi , Stefano Baiguera , G. Bruno De Luca , Andrea Legramandi , Giuseppe Nardelli , Nicolò Zenoni

Noncommutative K\"ahler structures were recently introduced as an algebraic framework for studying noncommutative complex geometry on quantum homogeneous spaces. In this paper, we introduce the notion of a \emph{compact quantum homogeneous…

Quantum Algebra · Mathematics 2026-03-17 Biswarup Das , Réamonn Ó Buachalla , Petr Somberg

Entanglement is the powerful and enigmatic resource central to quantum information processing, which promises capabilities in computing, simulation, secure communication, and metrology beyond what is possible for classical devices. Exactly…

We determine the ring structure of the equivariant quantum cohomology of the Hilbert scheme of points in the complex plane. The operator of quantum multiplication by the divisor class is a nonstationary deformation of the quantum…

Algebraic Geometry · Mathematics 2008-04-15 A. Okounkov , R. Pandharipande

The quantum states or Hilbert spaces for the quantum field theory in de Sitter space-time are studied on ambient space formalism. In this formalism, the quantum states are only depended $(1)$ on the topological character of the de Sitter…

General Relativity and Quantum Cosmology · Physics 2016-07-27 M. V. Takook

Starting from arbitrary Hilbert spaces, we reduce the problem to verify entanglement of any bipartite quantum state to finite dimensional subspaces. Hence, entanglement is a finite dimensional property. A generalization for multipartite…

Quantum Physics · Physics 2015-05-13 J. Sperling , W. Vogel

In this paper, we address a foundational challenge in quantum field theory on curved spacetime by developing a consistent framework within loop quantum gravity. We introduce a methodology for defining meaningful superpositions of quantum…

General Relativity and Quantum Cosmology · Physics 2026-02-17 Gaoping Long , Cong Zhang

Geometric properties of the set of quantum entangled states are investigated. We propose an explicit method to compute the dimension of local orbits for any mixed state of the general K x M problem and characterize the set of effectively…

Quantum Physics · Physics 2009-11-06 Marek Kus , Karol Zyczkowski

`Hypergeometric states', which are a one-parameter generalization of binomial states of the single-mode quantized radiation field, are introduced and their nonclassical properties are investigated. Their limits to the binomial states and to…

Quantum Physics · Physics 2008-11-26 Hong-Chen Fu , Ryu Sasaki

We attempt to reveal the geometry, emerged from the entanglement structure of any general $N$-party pure quantum many-body state by representing entanglement entropies corresponding to all $2^N $ bipartitions of the state by means of a…

A geometrical characterization of robustly separable (that is, remaining separable under sufficiently small variiations) mixed states of a bipartite quantum system is given. It is shown that the density matrix of any such state can be…

Quantum Physics · Physics 2007-05-23 Roman R. Zapatrin

In this note we present preliminary study on the relation between the quantum entanglement of boundary states and the quantum geometry in the bulk in the framework of spin networks. We conjecture that the emergence of space with non-zero…

High Energy Physics - Theory · Physics 2019-10-25 Yi Ling , Yikang Xiao , Meng-He Wu

We show that for any C*-algebra $A$, a sufficiently large Hilbert space $H$ and a unit vector $\xi \in H$, the natural application $rep(A:H) \to Q(A)$, $\pi \mapsto \langle \pi(-)\xi,\xi \rangle$ is a topological quotient, where $rep(A:H)$…

Operator Algebras · Mathematics 2015-01-30 Sergio Andrés Yuhjtman

Geometric quantum mechanics aims to express the physical properties of quantum systems in terms of geometrical features preferentially selected in the space of pure states. Geometric characterisations are given here for systems of one, two,…

Quantum Physics · Physics 2007-06-13 Dorje C. Brody , Anna C. T. Gustavsson , Lane P. Hughston

We isolate a geometric mechanism that complements the dynamical suppression of macroscopic interference: In a high-dimensional Hilbert space, almost all state vectors are nearly orthogonal, accommodating an exponentially large reservoir of…

Quantum Physics · Physics 2026-05-06 Karl Svozil

Motivated by the geometrical structures of quantum mechanics, we introduce an almost-complex structure $J$ on the product $M\times M$ of any parallelizable statistical manifold $M$. Then, we use $J$ to extract a pre-symplectic form and a…

Quantum Physics · Physics 2020-05-19 Florio M. Ciaglia , Fabio Di Cosmo , Armando Figueroa , Giuseppe Marmo , Luca Schiavone

We investigate entanglement measures in the infinite-dimensional regime. First, we discuss the peculiarities that may occur if the Hilbert space of a bi-partite system is infinite-dimensional, most notably the fact that the set of states…

Quantum Physics · Physics 2009-11-07 Jens Eisert , Christoph Simon , Martin B. Plenio

Hilbert space combines the properties of two fundamentally different types of mathematical spaces: vector space and metric space. While the vector-space aspects of Hilbert space, such as formation of linear combinations of state vectors,…

Quantum Physics · Physics 2015-05-27 I. D'Amico , J. P. Coe , V. V. Franca , K. Capelle

We show that the geometry of the set of quantum states plays a crucial role in the behavior of entanglement in different physical systems. More specifically it is shown that singular points at the border of the set of unentangled states…

We study the geometry of the space of densities $\VolM$, which is the quotient space $\Diff(M)/\Diff_\mu(M)$ of the diffeomorphism group of a compact manifold $M$ by the subgroup of volume-preserving diffemorphisms, endowed with a…

Differential Geometry · Mathematics 2011-05-04 Boris Khesin , Jonatan Lenells , Gerard Misiolek , Stephen C. Preston