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Related papers: A model of quantum spacetime

200 papers

A class of $k$-Essence cosmological models, with a power law kinetic term, is quantised in the mini-superspace. It is shown that for a specific configuration, corresponding to a pressureless fluid, a Schr\"odinger-type equation is obtained…

General Relativity and Quantum Cosmology · Physics 2016-12-28 C. R. Almeida , J. C. Fabris , F. Sbisá , Y. Tavakoli

Quantum reference frames have attracted renewed interest recently, as their exploration is relevant and instructive in many areas of quantum theory. Among the different types, position and time reference frames have captivated special…

Quantum Physics · Physics 2024-03-12 Michael Suleymanov , Ismael L. Paiva , Eliahu Cohen

By considering (non-relativistic) quantum mechanics as it is done in practice in particular in condensed-matter physics, it is argued that a deterministic, unitary time evolution within a chosen Hilbert space always has a limited scope,…

Quantum Physics · Physics 2017-10-03 Barbara Drossel

Among the many proposals to approach the concept of time in quantum theory, the Page-Wootters mechanism has attracted much attention in the last few years. Originally, such a mechanism explored a stationary bipartite non-interacting global…

Quantum Physics · Physics 2021-07-27 Leandro R. S. Mendes , Frederico Brito , Diogo O. Soares-Pinto

We consider a possibility to construct a quantum-mechanical model of spacetime, where Planck size quantum black holes act as the fundamental constituents of space and time. Spacetime is assumed to be a graph, where black holes lie on the…

General Relativity and Quantum Cosmology · Physics 2007-06-20 Jarmo Makela

The semi-classical approach to the quantum geometrodynamical model is used for the description of the properties of the universe on extremely small spacetime scales. Quantum theory for a homogeneous, isotropic and closed universe is…

General Relativity and Quantum Cosmology · Physics 2009-10-21 V. E. Kuzmichev , V. V. Kuzmichev

We present a generic way of thinking about time machines from the view of a far away observer. In this model the universe consists of three (or more) regions: One containing the entrance of the time machine, another the exit and the…

Quantum Physics · Physics 2007-05-23 Frank Antonsen , Karsten Bormann

The current accelerating phase of the evolution of the universe is considered by constructing most economical cosmic models that use just general relativity and some dominating quantum effects associated with the probabilistic description…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Pedro F. González-Díaz , Alberto Rozas-Fernández

We argue that theories of quantum gravity constructed with the help of (Causal) Dynamical Triangulations have given us the most informative, quantitative models to date of quantum spacetime. Most importantly, these are derived dynamically…

High Energy Physics - Theory · Physics 2015-06-15 J. Ambjorn , S. Jordan , J. Jurkiewicz , R. Loll

Doplicher, Fredenhagen, and Roberts (1994, 1995) proposed a simple model of a particle in quantum spacetime. We give a new formulation of the model and propose some small changes and additions which improve the physical interpretation. In…

High Energy Physics - Theory · Physics 2008-11-26 Jan Naudts , Maciej Kuna

This paper proposes an intrinsic or background-independent quantum framework based on entangled state rather than absolute quantum state, it describes a quantum relative state between the under-study quantum system and the quantum measuring…

Quantum Physics · Physics 2026-03-13 M. J. Luo

In general relativity, the picture of spacetime assigns an ideal clock to each worldline. Being ideal, gravitational effects due to these clocks are ignored and the flow of time according to one clock is not affected by the presence of…

Quantum Physics · Physics 2017-05-09 Esteban Castro-Ruiz , Flaminia Giacomini , Časlav Brukner

In the last years several theoretical papers discussed if time can be an emergent property deriving from quantum correlations. Here, to provide an insight into how this phenomenon can occur, we present an experiment that illustrates Page…

It is first pointed out that there is a common mathematical model for the universe and the quantum computer. The former is called the histories approach to quantum mechanics and the latter is called measurement based quantum computation.…

Quantum Physics · Physics 2022-09-01 Stan Gudder

We describe a theory amalgamating quantum theory and general relativity through the identification of a continuous 4-dimensional spacetime arena constructed from the substructures of a generalised multi-dimensional form for proper time. In…

General Physics · Physics 2020-10-07 David J. Jackson

Some principles underpinning the running of the Universe are discussed. The most important, the machine principle, states that the Universe is a fully autonomous, self-organizing and self-testing quantum automaton. Continuous space and…

Quantum Physics · Physics 2009-09-25 George Jaroszkiewicz

The rules of quantum mechanics require a time coordinate for their formulation. However, a notion of time is in general possible only when a classical spacetime geometry exists. Such a geometry is itself produced by classical matter…

Quantum Physics · Physics 2007-05-23 T. P. Singh

Effective quantum cosmology is formulated with a realistic global internal time given by the electric vector potential. New possibilities for the quantum behavior of space-time are found, and the high-density regime is shown to be very…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Stephon Alexander , Martin Bojowald , Antonino Marciano , David Simpson

We present exact quantum solutions for a noncommutative, multidimensional cosmological model and show that stabilization of extra dimensions sets in with the introduction of noncommutativity between the scale factors. An interpretation is…

General Relativity and Quantum Cosmology · Physics 2008-11-26 N. Khosravi , S. Jalalzadeh , H. R. Sepangi

We address the relation between two apparently distinct problems: The quest for a deeper understanding of the nature of consciousness and the search for time and space as emergent structures in the quantum mechanical world. We also advance…

History and Philosophy of Physics · Physics 2017-09-29 Augusto Cesar Lobo