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Related papers: A note on weight systems which are quantum states

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We present a description of the measurement process based on the parametric representation with environmental coherent states. This representation is specifically tailored for studying quantum systems whose environment needs being…

Quantum Physics · Physics 2015-09-30 Pietro Liuzzo-Scorpo , Alessandro Cuccoli , Paola Verrucchi

Qubits have been designed in the framework of quantum mechanics. Attempts to formulate the problem in the language of quantum field theory have been proposed already. In this short note we refine the meaning of qubits within the framework…

Quantum Physics · Physics 2015-06-03 Jacques Calmet , Xavier Calmet

We present a geometrical description of the space of density states of a quantum system of finite dimension. After presenting a brief summary of the geometrical formulation of Quantum Mechanics, we proceed to describe the space of density…

Quantum Physics · Physics 2007-07-26 J. Clemente-Gallardo , G. Marmo

We construct quantum states for a (1+1) dimensional gravity-matter model that is also a gauge theory based on the centrally extended Poincar\'e group. Explicit formulas are found, which exhibit interesting structures. For example wave…

High Energy Physics - Theory · Physics 2009-10-28 D. Cangemi , R. Jackiw

A state sum model based on the group SU(1,1) is defined. Investigations of its geometry and asymptotics suggest it is a good candidate for modelling (2+1) Lorentzian quantum gravity.

General Relativity and Quantum Cosmology · Physics 2009-09-25 Stefan Davids

One of the most central and controversial element of quantum mechanics is the use of non zero vectors of a Hilbert space (or, more generally, of one dimension subspaces) for representing the state of a quantum system. In particular, the…

Quantum Physics · Physics 2009-11-13 Olivier Brunet

We define bulk/boundary maps corresponding to quantum gravity states in the tensorial group field theory formalism, for quantum geometric models sharing the same type of quantum states of loop quantum gravity. The maps are defined in terms…

High Energy Physics - Theory · Physics 2022-04-06 Eugenia Colafranceschi , Goffredo Chirco , Daniele Oriti

The quantum state overlap is the textbook measure of the difference between two quantum states. Yet, it is inadequate to compare the complex configurations of many-body systems. The problem is inherited by the widely employed quantum state…

Quantum Physics · Physics 2021-06-03 Davide Girolami , Fabio Anzà

We study quantum and classical systems associated with the quantum corner symmetry group $\mathrm{QCS}=\widetilde{\mathrm{SL}}(2,\mathbb{R})\ltimes \mathrm{H}_3,$ which arises in the context of quantum gravity. We relate quantum observables…

High Energy Physics - Theory · Physics 2026-03-03 Ludovic Varrin

The quantum measurement problem considered for the model of measuring system (MS) consist of measured state S (particle), detector D and information processing device (observer) $O$ interacting with S,D. For 'external' observer $O'$ MS…

Quantum Physics · Physics 2007-05-23 Mayburov. S

Measurement-based quantum computing enables universal quantum computing with only adaptive single-qubit measurements on certain many-qubit states, such as the graph state, the Affleck-Kennedy-Lieb-Tasaki (AKLT) state, and several…

Quantum Physics · Physics 2017-11-15 Tomoyuki Morimae

An exposition of quantum permutation groups where an alternative to the 'Gelfand picture' of compact quantum groups is proposed. This point of view is inspired by algebraic quantum mechanics and posits that states on the algebra of…

Quantum Algebra · Mathematics 2021-10-28 J. P. McCarthy

We investigate the geometrical and combinatorial structures of multipartite quantum systems based on conifold and toric variety. In particular, we study the relations between resolution of conifold, toric variety, a separable state, and a…

Quantum Physics · Physics 2014-04-25 Hoshang Heydari

There is a longstanding debate on the metaphysical relation between quantum states and the systems they describe. A series of relatively recent {\psi}-ontology theorems have been taken to show that, provided one accepts certain assumptions,…

Quantum Physics · Physics 2021-04-07 Ronnie Hermens

A fundamental problem in quantum information is to describe efficiently multipartite quantum states. An efficient representation in terms of graphs exists for several families of quantum states (graph, cluster, stabilizer states),…

Quantum Physics · Physics 2012-07-04 Radu Ionicioiu , Tim P. Spiller

Quantum field theory (QFT) on non-stationary spacetimes is well understood from the side of the algebra of observables. The state space, however, is largely unexplored, due to the non-existence of distinguished states (vacuum, scattering…

General Relativity and Quantum Cosmology · Physics 2018-09-25 Klaus Fredenhagen , Thomas-Paul Hack , Nicola Pinamonti

The GNS representation construction is considered in a general case of topological involutive algebras of quantum systems, including quantum fields, and inequivalent state spaces of these systems are characterized. We aim to show that, from…

Mathematical Physics · Physics 2015-08-17 G. Sardanashvily

A hypergeometric type equation satisfying certain conditions defines either a finite or an infinite system of orthogonal polynomials. We present in a unified and explicit way all these systems of orthogonal polynomials, the associated…

Mathematical Physics · Physics 2015-06-26 Nicolae Cotfas

In this paper we investigate the bound state problem of nonrelativistic quantum particles on a conical surface. This kind of surface appears as a topological defect in ordinary semiconductors as well as in graphene sheets. Specifically, we…

Quantum Physics · Physics 2012-12-13 C. Filgueiras , E. O. Silva , F. M. Andrade

We provide formulas for invariants defined on a tensor product of defining representations of unitary groups, under the action of the product group. This situation has a physical interpretation, as it is related to the quantum mechanical…

Representation Theory · Mathematics 2011-11-01 Michael W. Hero , Jeb F. Willenbring , Lauren Kelly Williams