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Related papers: Weaving a classical geometry with quantum threads

200 papers

We study the action of space-time symmetries on quantum fields in the presence of small departures from locality determined by dynamical gravity. It is shown that, under such relaxation of locality, the symmetries of the theory cannot be…

High Energy Physics - Theory · Physics 2008-11-26 Michele Arzano

A new approach to a unified theory of quantum gravity based on noncommutative geometry and canonical quantum gravity is presented. The approach is built around a *-algebra generated by local holonomy-diffeomorphisms on a 3-manifold and a…

Mathematical Physics · Physics 2015-06-11 Johannes Aastrup , Jesper M. Grimstrup

A functional calculus on the space of (generalized) connections was recently introduced without any reference to a background metric. It is used to continue the exploration of the quantum Riemannian geometry. Operators corresponding to…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Abhay Ashtekar , Jerzy Lewandowski

The concept of fixed-area states has proven useful for recent studies of quantum gravity, especially in connection with gravitational holography. We explore the Lorentz-signature spacetime geometry intrinsic to such fixed-area states in…

High Energy Physics - Theory · Physics 2022-09-07 Xi Dong , Donald Marolf , Pratik Rath , Amirhossein Tajdini , Zhencheng Wang

Observable properties of a classical physical system can be modelled deterministically as functions from the space of pure states to outcomes; dually, states can be modelled as functions from the algebra of observables to outcomes. The…

Operator Algebras · Mathematics 2021-03-09 Nadish de Silva , Rui Soares Barbosa

Gedanken experiments in quantum gravity motivate generalised uncertainty relations (GURs) implying deviations from the standard quantum statistics close to the Planck scale. These deviations have been extensively investigated for the…

Quantum Physics · Physics 2021-03-30 Matthew J. Lake

We review applications of noncommutative geometry in canonical quantum gravity. First, we show that the framework of loop quantum gravity includes natural noncommutative structures which have, hitherto, not been explored. Next, we present…

General Relativity and Quantum Cosmology · Physics 2012-03-29 Johannes Aastrup , Jesper M. Grimstrup

We argue in a model-independent way that the Hilbert space of quantum gravity is locally finite-dimensional. In other words, the density operator describing the state corresponding to a small region of space, when such a notion makes sense,…

High Energy Physics - Theory · Physics 2017-11-22 Ning Bao , Sean M. Carroll , Ashmeet Singh

The discrete picture of geometry arising from the loop representation of quantum gravity can be extended by a quantum deformation. The operators for area and volume defined in the q-deformation of the theory are partly diagonalized. The…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Roumen Borissov , Seth Major , Lee Smolin

In this work, we extend the so-called typicality approach, originally formulated in statistical mechanics contexts, to $SU(2)$-invariant spin-network states. Our results do not depend on the physical interpretation of the spin network;…

General Relativity and Quantum Cosmology · Physics 2016-11-02 Fabio Anzà , Goffredo Chirco

Physical properties of the quantum gravitational vacuum state are explored by solving a lattice version of the Wheeler-DeWitt equation. The constraint of diffeomorphism invariance is strong enough to uniquely determine the structure of the…

High Energy Physics - Theory · Physics 2015-06-12 Herbert W. Hamber , Reiko Toriumi , Ruth M. Williams

We investigate the relationship between nonlocal and local quantum field theories, and search for a viable notion of "local limit" to relate the unitary models. In Euclidean space it is relatively easy to have nonlocal theories with…

High Energy Physics - Theory · Physics 2025-09-17 Damiano Anselmi

The nonrelativistic limit of nonlocal modifications to the Klein Gordon operator is studied, and the experimental possibilities of casting stringent constraints on the nonlocality scale via planned and/or current optomechanical experiments…

General Relativity and Quantum Cosmology · Physics 2017-02-01 Alessio Belenchia , Dionigi M. T. Benincasa , Stefano Liberati , Francesco Marin , Francesco Marino , Antonello Ortolan

The dual picture of quantum geometry provided by a spin network state is discussed. From this perspective, we introduce a new operator in Loop Quantum Gravity - the length operator. We describe its quantum geometrical meaning and derive…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Eugenio Bianchi

We have constructed a non-relativistic theory of quantum mechanics based on local modulus symmetry. The resulting connection in the covariant derivative is identified as the escape velocity of the gravitational field. A new real and…

General Relativity and Quantum Cosmology · Physics 2025-03-18 Tao Zhou

The basic framework for a systematic construction of a quantum theory of Riemannian geometry was introduced recently. The quantum versions of Riemannian structures --such as triad and area operators-- exhibit a non-commutativity. At first…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Abhay Ashtekar , Alejandro Corichi , Jose. A. Zapata

Quantum mechanics in its presently known formulation requires an external classical time for its description. A classical spacetime manifold and a classical spacetime metric are produced by classical matter fields. In the absence of such…

General Relativity and Quantum Cosmology · Physics 2008-11-26 T. P. Singh

We study quantum field theories which have quantum groups as global internal symmetries. We show that in such theories operators are generically non-local, and should be thought as living at the ends of topological lines. We describe the…

High Energy Physics - Theory · Physics 2025-08-25 Barak Gabai , Victor Gorbenko , Jiaxin Qiao , Bernardo Zan , Aleksandr Zhabin

In this paper we point out some possible links between different approaches to quantum gravity and theories of the Planck scale physics. In particular, connections between Loop Quantum Gravity, Causal Dynamical Triangulations,…

High Energy Physics - Theory · Physics 2018-05-28 Jakub Mielczarek , Tomasz Trześniewski

We show that the non-locality recently identified in quantum gravity using resummation techniques propagates to the matter sector of the theory. We describe these non-local effects using effective field theory techniques. We derive the…

High Energy Physics - Theory · Physics 2017-11-28 S. O. Alexeyev , X. Calmet , B. N. Latosh