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Related papers: Quantum de Sitter geometry

200 papers

Considering homogeneous four-dimensional space-time geometries within real projective geometry provides a mathematically well-defined framework to discuss their deformations and limits without the appearance of coordinate singularities. On…

Mathematical Physics · Physics 2025-05-22 Daniel Spitz

The properties of the quantum universe on extremely small spacetime scales are studied in the semi-classical approach to the well-defined quantum model. It is shown that near the initial cosmological singularity point quantum gravity…

General Relativity and Quantum Cosmology · Physics 2010-04-30 V. E. Kuzmichev , V. V. Kuzmichev

We consider quantum field theory in de Sitter space, focusing on the cases of scalars, spin 1/2 fields, and symmetric and anti-symmetric tensor fields of arbitrary spin. The free field equations in global coordinates can be reduced to a one…

High Energy Physics - Theory · Physics 2011-06-16 Philip Lagogiannis , Alexander Maloney , Yi Wang

The concept of quantum geometry for single-particle states has revolutionized our interpretation of several emergent properties in condensed matter. However, a description of the quantum geometry for interacting particles and an…

Materials Science · Physics 2025-08-12 MingRui Lai , Fengyuan Xuan , Su Ying Quek

We consider the quantum description of a toy model universe in which the Schwarzschild-de Sitter geometry emerges from the coherent state of a massless scalar field. Although highly idealised, this simple model allows us to find clear hints…

General Relativity and Quantum Cosmology · Physics 2022-01-19 Andrea Giusti , Silvia Buffa , Lavinia Heisenberg , Roberto Casadio

The method of geometric quantization is applied to a particle moving on an arbitrary Riemannian manifold $Q$ in an external gauge field, that is a connection on a principal $H$-bundle $N$ over $Q$. The phase space of the particle is a…

High Energy Physics - Theory · Physics 2015-06-26 M. A. Robson

If one tries to view de Sitter as a true (as opposed to a meta-stable) vacuum, there is a tension between the finiteness of its entropy and the infinite-dimensionality of its Hilbert space. We invetsigate the viability of one proposal to…

High Energy Physics - Theory · Physics 2008-11-26 Chethan Krishnan , Edoardo Di Napoli

Understanding the geometric information contained in quantum states is valuable in various branches of physics, particularly in solid-state physics when Bloch states play a crucial role. While the Fubini-Study metric and Berry curvature…

Quantum Physics · Physics 2024-04-05 Alexander Avdoshkin

This article sets out the framework of algebraic quantum field theory in curved spacetimes, based on the idea of local covariance. In this framework, a quantum field theory is modelled by a functor from a category of spacetimes to a…

Mathematical Physics · Physics 2015-04-03 Christopher J. Fewster , Rainer Verch

The complete quantum metric of a parametrized quantum system has a real part (usually known as the Provost-Vallee metric) and a symplectic imaginary part (known as the Berry curvature). In this paper, we first investigate the relation…

Quantum Physics · Physics 2023-10-02 Balázs Hetényi , Péter Lévay

We introduce a new model of background independent physics in which the degrees of freedom live on a complete graph and the physics is invariant under the permutations of all the points. We argue that the model has a low energy phase in…

High Energy Physics - Theory · Physics 2007-05-23 Tomasz Konopka , Fotini Markopoulou , Lee Smolin

Without a complete theory of quantum gravity, the question of how quantum fields and quantum particles behave in a superposition of spacetimes seems beyond the reach of theoretical and experimental investigations. Here we use an extension…

We apply Lie algebra deformation theory to the problem of identifying the stable form of the quantum relativistic kinematical algebra. As a warm up, given Galileo's conception of spacetime as input, some modest computer code we wrote zeroes…

High Energy Physics - Theory · Physics 2009-11-10 C. Chryssomalakos , E. Okon

In de Sitter ambient space formalism, the linear gravity can be written in terms of a minimally coupled scalar field and a polarization tensor. In this formalism, the massless minimally coupled scalar field can be quantized on Bunch-Davies…

General Relativity and Quantum Cosmology · Physics 2017-08-21 M. V. Takook , S. Rouhani

Excitations of a relativistic geometry are used to represent the theory of quantum electrodynamics. The connection excitations and the frame excitations reduce, respectively, to the electromagnetic field operator and electron field…

General Physics · Physics 2007-05-23 Gustavo R. Gonzalez-Martin

In quantum field theory the creation and annihilation operators that are located at the points in 3-momentum space have commutation relations that are conserved under the action of a $U({\infty})$ group. Here it is shown how to define an…

High Energy Physics - Theory · Physics 2007-05-23 Achim Kempf

A generalised definition of the metric of quantum states is proposed by using the techniques of differential geometry. The metric of quantum state space derived earlier by Anandan, is reproduced and verified here by this generalised…

Quantum Physics · Physics 2007-05-23 Aalok Pandya , Ashok K. Nagawat

We perform a foliation of a four dimensional Riemannian space-time with respect to a discrete time which is an integer multiple of the Planck time. We find that the quantum fluctuations of the metric have a discrete energy spectrum. The…

High Energy Physics - Theory · Physics 2007-05-23 P. A. Zizzi

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

Geometric quantum mechanics, through its differential-geometric underpinning, provides additional tools of analysis and interpretation that bring quantum mechanics closer to classical mechanics: state spaces in both are equipped with…

Quantum Physics · Physics 2024-05-08 Fabio Anza , James P. Crutchfield