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Related papers: Semiclassical analysis of the Loop Quantum Gravity…

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We show that it is possible to still use semiclassical gravity together with quantum field theory beyond the regimes where the field state is coherent. In particular, we identify families of cat states (superposition of…

Quantum Physics · Physics 2024-01-29 Shahnewaz Ahmed , Caroline Lima , Eduardo Martín-Martínez

When dealing with the classical limit of two quantum mechanical oscillators on a noncommutative configuration space, the limits corresponding to the removal of configuration-space noncommutativity and position-momentum noncommutativity do…

Quantum Physics · Physics 2016-01-20 Fabio Benatti , Laure Gouba

We construct an operator that measures the length of a curve in four-dimensional Lorentzian vacuum quantum gravity. We work in a representation in which a $SU(2)$ connection is diagonal and it is therefore surprising that the operator…

General Relativity and Quantum Cosmology · Physics 2009-10-28 T. Thiemann

Inspired by special and general relativistic systems that can have Hamiltonians involving square roots, or more general fractional powers, in this article we address the question how a suitable set of coherent states for such systems can be…

General Relativity and Quantum Cosmology · Physics 2021-11-18 Kristina Giesel , Almut Vetter

In this paper we calculated the spectral dimension of loop quantum gravity (LQG) using the scaling property of the area operator spectrum on spin-network states and using the scaling property of the volume and length operators on Gaussian…

General Relativity and Quantum Cosmology · Physics 2009-05-19 Leonardo Modesto

One of the most important issues in quantum gravity is to identify its semi-classical regime. First the issue is to define for we mean by a semi-classical theory of quantum gravity, then we would like to use it to extract physical…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Etera R. Livine

Since there are quantization ambiguities in constructing the Hamiltonian constraint operator in isotropic loop quantum cosmology, it is crucial to check whether the key features of loop quantum cosmology, such as the quantum bounce and…

General Relativity and Quantum Cosmology · Physics 2009-04-28 Jinsong Yang , You Ding , Yongge Ma

We introduce a minimalistic notion of semiclassical quantization and use it to prove that the convex hull of the semiclassical spectrum of a quantum system given by a collection of commuting operators converges to the convex hull of the…

Mathematical Physics · Physics 2017-05-17 Álvaro Pelayo , Leonid Polterovich , San Vũ Ngoc

Calculations in Loop Quantum Gravity (LQG) and spin-foams theory rely heavily on group theory of SU(2) and SL(2,C). Even though many monographs exist devoted to this theory, the different tools needed (e.g. representation theory, harmonic…

Mathematical Physics · Physics 2022-11-21 Pierre Martin-Dussaud

Coherent state operators (CSO) are defined as operator valued functions on G=SL(n,C), homogeneous with respect to right multiplication by lower triangular matrices. They act on a model space containing all holomorphic finite dimensional…

High Energy Physics - Theory · Physics 2009-10-28 H. Sazdjian , Y. S. Stanev , I. T. Todorov

We do not observe quantum effects on cosmological scales. Thus, if loop quantum cosmology (LQC) is to provide an accurate depiction of the real world, it must allow for quantum states of spacetime geometry which are semi-classical in two…

General Relativity and Quantum Cosmology · Physics 2021-04-28 Patrick Fraser

Understanding the complexity of quantum states and circuits is a central challenge in quantum information science, with broad implications in many-body physics, high-energy physics and quantum learning theory. A common way to model the…

Quantum Physics · Physics 2026-05-15 Oxana Shaya , Zoë Holmes , Christoph Hirche , Armando Angrisani

One of the main achievements of LQG is the consistent quantization of the Wheeler-DeWitt equation which is free of UV problems. However, ambiguities associated to the intermediate regularization procedure lead to an apparently infinite set…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Alejandro Perez

We present a general procedure for constructing new Hilbert spaces for loop quantum gravity on non-compact spatial manifolds. Given any fixed background state representing a non-compact spatial geometry, we use the Gel'fand-Naimark-Segal…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Matthias Arnsdorf , Sameer Gupta

A covariant spin-foam formulation of quantum gravity has been recently developed, characterized by a kinematics which appears to match well the one of canonical loop quantum gravity. In particular, the geometrical observable giving the area…

General Relativity and Quantum Cosmology · Physics 2014-11-20 You Ding , Carlo Rovelli

Loop quantum gravity (LQG) attempts to unify general relativity with quantum physics to offer a complete description of the universe by quantising spacetime geometry, but the numerical calculations we encounter are extraordinarily…

General Relativity and Quantum Cosmology · Physics 2025-11-21 Ben Priestley

We introduce and systematically develop the theory of \emph{quantum doubly stochastic operators}, i.e. positive, trace-preserving maps on non-commutative $L_p$-spaces associated to semifinite von Neumann algebras. After establishing basic…

Operator Algebras · Mathematics 2026-05-19 Emma Sulaver

We introduce a new top down approach to canonical quantum gravity, called Algebraic Quantum Gravity (AQG):The quantum kinematics of AQG is determined by an abstract $*-$algebra generated by a countable set of elementary operators labelled…

General Relativity and Quantum Cosmology · Physics 2008-11-26 K. Giesel , T. Thiemann

In this paper we provide the techniques and proofs for the resuls presented in our companion paper concerning the consistency check on volume and triad operator quantisation in Loop Quantum Gravity.

General Relativity and Quantum Cosmology · Physics 2017-01-18 Kristina Giesel , Thomas Thiemann

An operator space analysis of quantum stochastic cocycles is undertaken. These are cocycles with respect to an ampliated CCR flow, adapted to the associated filtration of subspaces, or subalgebras. They form a noncommutative analogue of…

Operator Algebras · Mathematics 2011-01-04 J. Martin Lindsay , Stephen J. Wills